BulletSim initial checkin

23 files changed, 5679 insertions, 0 deletions

diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/CTri.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/CTri.cs
new file mode 100644
index 0000000..4d84c44
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/CTri.cs
@@ -0,0 +1,341 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class Wpoint
+    {
+        public float3 mPoint;
+        public float mWeight;
+
+        public Wpoint(float3 p, float w)
+        {
+            mPoint = p;
+            mWeight = w;
+        }
+    }
+
+    public class CTri
+    {
+        private const int WSCALE = 4;
+
+        public float3 mP1;
+        public float3 mP2;
+        public float3 mP3;
+        public float3 mNear1;
+        public float3 mNear2;
+        public float3 mNear3;
+        public float3 mNormal;
+        public float mPlaneD;
+        public float mConcavity;
+        public float mC1;
+        public float mC2;
+        public float mC3;
+        public int mI1;
+        public int mI2;
+        public int mI3;
+        public int mProcessed; // already been added...
+
+        public CTri(float3 p1, float3 p2, float3 p3, int i1, int i2, int i3)
+        {
+            mProcessed = 0;
+            mI1 = i1;
+            mI2 = i2;
+            mI3 = i3;
+
+            mP1 = new float3(p1);
+            mP2 = new float3(p2);
+            mP3 = new float3(p3);
+
+            mNear1 = new float3();
+            mNear2 = new float3();
+            mNear3 = new float3();
+
+            mNormal = new float3();
+            mPlaneD = mNormal.ComputePlane(mP1, mP2, mP3);
+        }
+
+        public float Facing(CTri t)
+        {
+            return float3.dot(mNormal, t.mNormal);
+        }
+
+        public bool clip(float3 start, ref float3 end)
+        {
+            float3 sect = new float3();
+            bool hit = lineIntersectsTriangle(start, end, mP1, mP2, mP3, ref sect);
+
+            if (hit)
+                end = sect;
+            return hit;
+        }
+
+        public bool Concave(float3 p, ref float distance, ref float3 n)
+        {
+            n.NearestPointInTriangle(p, mP1, mP2, mP3);
+            distance = p.Distance(n);
+            return true;
+        }
+
+        public void addTri(int[] indices, int i1, int i2, int i3, ref int tcount)
+        {
+            indices[tcount * 3 + 0] = i1;
+            indices[tcount * 3 + 1] = i2;
+            indices[tcount * 3 + 2] = i3;
+            tcount++;
+        }
+
+        public float getVolume()
+        {
+            int[] indices = new int[8 * 3];
+
+            int tcount = 0;
+
+            addTri(indices, 0, 1, 2, ref tcount);
+            addTri(indices, 3, 4, 5, ref tcount);
+
+            addTri(indices, 0, 3, 4, ref tcount);
+            addTri(indices, 0, 4, 1, ref tcount);
+
+            addTri(indices, 1, 4, 5, ref tcount);
+            addTri(indices, 1, 5, 2, ref tcount);
+
+            addTri(indices, 0, 3, 5, ref tcount);
+            addTri(indices, 0, 5, 2, ref tcount);
+
+            List<float3> vertices = new List<float3> { mP1, mP2, mP3, mNear1, mNear2, mNear3 };
+            List<int> indexList = new List<int>(indices);
+
+            float v = Concavity.computeMeshVolume(vertices, indexList);
+            return v;
+        }
+
+        public float raySect(float3 p, float3 dir, ref float3 sect)
+        {
+            float4 plane = new float4();
+
+            plane.x = mNormal.x;
+            plane.y = mNormal.y;
+            plane.z = mNormal.z;
+            plane.w = mPlaneD;
+
+            float3 dest = p + dir * 100000f;
+
+            intersect(p, dest, ref sect, plane);
+
+            return sect.Distance(p); // return the intersection distance
+        }
+
+        public float planeDistance(float3 p)
+        {
+            float4 plane = new float4();
+
+            plane.x = mNormal.x;
+            plane.y = mNormal.y;
+            plane.z = mNormal.z;
+            plane.w = mPlaneD;
+
+            return DistToPt(p, plane);
+        }
+
+        public bool samePlane(CTri t)
+        {
+            const float THRESH = 0.001f;
+            float dd = Math.Abs(t.mPlaneD - mPlaneD);
+            if (dd > THRESH)
+                return false;
+            dd = Math.Abs(t.mNormal.x - mNormal.x);
+            if (dd > THRESH)
+                return false;
+            dd = Math.Abs(t.mNormal.y - mNormal.y);
+            if (dd > THRESH)
+                return false;
+            dd = Math.Abs(t.mNormal.z - mNormal.z);
+            if (dd > THRESH)
+                return false;
+            return true;
+        }
+
+        public bool hasIndex(int i)
+        {
+            if (i == mI1 || i == mI2 || i == mI3)
+                return true;
+            return false;
+        }
+
+        public bool sharesEdge(CTri t)
+        {
+            bool ret = false;
+            uint count = 0;
+
+            if (t.hasIndex(mI1))
+                count++;
+            if (t.hasIndex(mI2))
+                count++;
+            if (t.hasIndex(mI3))
+                count++;
+
+            if (count >= 2)
+                ret = true;
+
+            return ret;
+        }
+
+        public float area()
+        {
+            float a = mConcavity * mP1.Area(mP2, mP3);
+            return a;
+        }
+
+        public void addWeighted(List<Wpoint> list)
+        {
+            Wpoint p1 = new Wpoint(mP1, mC1);
+            Wpoint p2 = new Wpoint(mP2, mC2);
+            Wpoint p3 = new Wpoint(mP3, mC3);
+
+            float3 d1 = mNear1 - mP1;
+            float3 d2 = mNear2 - mP2;
+            float3 d3 = mNear3 - mP3;
+
+            d1 *= WSCALE;
+            d2 *= WSCALE;
+            d3 *= WSCALE;
+
+            d1 = d1 + mP1;
+            d2 = d2 + mP2;
+            d3 = d3 + mP3;
+
+            Wpoint p4 = new Wpoint(d1, mC1);
+            Wpoint p5 = new Wpoint(d2, mC2);
+            Wpoint p6 = new Wpoint(d3, mC3);
+
+            list.Add(p1);
+            list.Add(p2);
+            list.Add(p3);
+
+            list.Add(p4);
+            list.Add(p5);
+            list.Add(p6);
+        }
+
+        private static float DistToPt(float3 p, float4 plane)
+            {
+                    float x = p.x;
+                    float y = p.y;
+                    float z = p.z;
+                    float d = x*plane.x + y*plane.y + z*plane.z + plane.w;
+                    return d;
+            }
+
+        private static void intersect(float3 p1, float3 p2, ref float3 split, float4 plane)
+        {
+            float dp1 = DistToPt(p1, plane);
+
+            float3 dir = new float3();
+            dir.x = p2[0] - p1[0];
+            dir.y = p2[1] - p1[1];
+            dir.z = p2[2] - p1[2];
+
+            float dot1 = dir[0] * plane[0] + dir[1] * plane[1] + dir[2] * plane[2];
+            float dot2 = dp1 - plane[3];
+
+            float t = -(plane[3] + dot2) / dot1;
+
+            split.x = (dir[0] * t) + p1[0];
+            split.y = (dir[1] * t) + p1[1];
+            split.z = (dir[2] * t) + p1[2];
+        }
+
+        private static bool rayIntersectsTriangle(float3 p, float3 d, float3 v0, float3 v1, float3 v2, out float t)
+        {
+            t = 0f;
+
+            float3 e1, e2, h, s, q;
+            float a, f, u, v;
+
+            e1 = v1 - v0;
+            e2 = v2 - v0;
+            h = float3.cross(d, e2);
+            a = float3.dot(e1, h);
+
+            if (a > -0.00001f && a < 0.00001f)
+                return false;
+
+            f = 1f / a;
+            s = p - v0;
+            u = f * float3.dot(s, h);
+
+            if (u < 0.0f || u > 1.0f)
+                return false;
+
+            q = float3.cross(s, e1);
+            v = f * float3.dot(d, q);
+            if (v < 0.0f || u + v > 1.0f)
+                return false;
+
+            // at this stage we can compute t to find out where
+            // the intersection point is on the line
+            t = f * float3.dot(e2, q);
+            if (t > 0f) // ray intersection
+                return true;
+            else // this means that there is a line intersection but not a ray intersection
+                return false;
+        }
+
+        private static bool lineIntersectsTriangle(float3 rayStart, float3 rayEnd, float3 p1, float3 p2, float3 p3, ref float3 sect)
+        {
+            float3 dir = rayEnd - rayStart;
+
+            float d = (float)Math.Sqrt(dir[0] * dir[0] + dir[1] * dir[1] + dir[2] * dir[2]);
+            float r = 1.0f / d;
+
+            dir *= r;
+
+            float t;
+            bool ret = rayIntersectsTriangle(rayStart, dir, p1, p2, p3, out t);
+
+            if (ret)
+            {
+                if (t > d)
+                {
+                    sect.x = rayStart.x + dir.x * t;
+                    sect.y = rayStart.y + dir.y * t;
+                    sect.z = rayStart.z + dir.z * t;
+                }
+                else
+                {
+                    ret = false;
+                }
+            }
+
+            return ret;
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/Concavity.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/Concavity.cs
new file mode 100644
index 0000000..cc6383a
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/Concavity.cs
@@ -0,0 +1,233 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public static class Concavity
+    {
+        // compute's how 'concave' this object is and returns the total volume of the
+        // convex hull as well as the volume of the 'concavity' which was found.
+        public static float computeConcavity(List<float3> vertices, List<int> indices, ref float4 plane, ref float volume)
+        {
+            float cret = 0f;
+            volume = 1f;
+
+            HullResult result = new HullResult();
+            HullDesc desc = new HullDesc();
+
+            desc.MaxFaces = 256;
+            desc.MaxVertices = 256;
+            desc.SetHullFlag(HullFlag.QF_TRIANGLES);
+            desc.Vertices = vertices;
+
+            HullError ret = HullUtils.CreateConvexHull(desc, ref result);
+
+            if (ret == HullError.QE_OK)
+            {
+                volume = computeMeshVolume2(result.OutputVertices, result.Indices);
+
+                // ok..now..for each triangle on the original mesh..
+                // we extrude the points to the nearest point on the hull.
+                List<CTri> tris = new List<CTri>();
+
+                for (int i = 0; i < result.Indices.Count / 3; i++)
+                {
+                    int i1 = result.Indices[i * 3 + 0];
+                    int i2 = result.Indices[i * 3 + 1];
+                    int i3 = result.Indices[i * 3 + 2];
+
+                    float3 p1 = result.OutputVertices[i1];
+                    float3 p2 = result.OutputVertices[i2];
+                    float3 p3 = result.OutputVertices[i3];
+
+                    CTri t = new CTri(p1, p2, p3, i1, i2, i3);
+                    tris.Add(t);
+                }
+
+                // we have not pre-computed the plane equation for each triangle in the convex hull..
+                float totalVolume = 0;
+
+                List<CTri> ftris = new List<CTri>(); // 'feature' triangles.
+                List<CTri> input_mesh = new List<CTri>();
+
+                for (int i = 0; i < indices.Count / 3; i++)
+                {
+                    int i1 = indices[i * 3 + 0];
+                    int i2 = indices[i * 3 + 1];
+                    int i3 = indices[i * 3 + 2];
+
+                    float3 p1 = vertices[i1];
+                    float3 p2 = vertices[i2];
+                    float3 p3 = vertices[i3];
+
+                    CTri t = new CTri(p1, p2, p3, i1, i2, i3);
+                    input_mesh.Add(t);
+                }
+
+                for (int i = 0; i < indices.Count / 3; i++)
+                {
+                    int i1 = indices[i * 3 + 0];
+                    int i2 = indices[i * 3 + 1];
+                    int i3 = indices[i * 3 + 2];
+
+                    float3 p1 = vertices[i1];
+                    float3 p2 = vertices[i2];
+                    float3 p3 = vertices[i3];
+
+                    CTri t = new CTri(p1, p2, p3, i1, i2, i3);
+
+                    featureMatch(t, tris, input_mesh);
+
+                    if (t.mConcavity > 0.05f)
+                    {
+                        float v = t.getVolume();
+                        totalVolume += v;
+                        ftris.Add(t);
+                    }
+                }
+
+                SplitPlane.computeSplitPlane(vertices, indices, ref plane);
+                cret = totalVolume;
+            }
+
+            return cret;
+        }
+
+        public static bool featureMatch(CTri m, List<CTri> tris, List<CTri> input_mesh)
+        {
+            bool ret = false;
+            float neardot = 0.707f;
+            m.mConcavity = 0;
+
+            for (int i = 0; i < tris.Count; i++)
+            {
+                CTri t = tris[i];
+
+                if (t.samePlane(m))
+                {
+                    ret = false;
+                    break;
+                }
+
+                float dot = float3.dot(t.mNormal, m.mNormal);
+
+                if (dot > neardot)
+                {
+                    float d1 = t.planeDistance(m.mP1);
+                    float d2 = t.planeDistance(m.mP2);
+                    float d3 = t.planeDistance(m.mP3);
+
+                    if (d1 > 0.001f || d2 > 0.001f || d3 > 0.001f) // can't be near coplaner!
+                    {
+                        neardot = dot;
+
+                        t.raySect(m.mP1, m.mNormal, ref m.mNear1);
+                        t.raySect(m.mP2, m.mNormal, ref m.mNear2);
+                        t.raySect(m.mP3, m.mNormal, ref m.mNear3);
+
+                        ret = true;
+                    }
+                }
+            }
+
+            if (ret)
+            {
+                m.mC1 = m.mP1.Distance(m.mNear1);
+                m.mC2 = m.mP2.Distance(m.mNear2);
+                m.mC3 = m.mP3.Distance(m.mNear3);
+
+                m.mConcavity = m.mC1;
+
+                if (m.mC2 > m.mConcavity)
+                    m.mConcavity = m.mC2;
+                if (m.mC3 > m.mConcavity)
+                    m.mConcavity = m.mC3;
+            }
+
+            return ret;
+        }
+
+        private static float det(float3 p1, float3 p2, float3 p3)
+        {
+            return p1.x * p2.y * p3.z + p2.x * p3.y * p1.z + p3.x * p1.y * p2.z - p1.x * p3.y * p2.z - p2.x * p1.y * p3.z - p3.x * p2.y * p1.z;
+        }
+
+        public static float computeMeshVolume(List<float3> vertices, List<int> indices)
+        {
+            float volume = 0f;
+
+            for (int i = 0; i < indices.Count / 3; i++)
+            {
+                float3 p1 = vertices[indices[i * 3 + 0]];
+                float3 p2 = vertices[indices[i * 3 + 1]];
+                float3 p3 = vertices[indices[i * 3 + 2]];
+
+                volume += det(p1, p2, p3); // compute the volume of the tetrahedran relative to the origin.
+            }
+
+            volume *= (1.0f / 6.0f);
+            if (volume < 0f)
+                return -volume;
+            return volume;
+        }
+
+        public static float computeMeshVolume2(List<float3> vertices, List<int> indices)
+        {
+            float volume = 0f;
+
+            float3 p0 = vertices[0];
+            for (int i = 0; i < indices.Count / 3; i++)
+            {
+                float3 p1 = vertices[indices[i * 3 + 0]];
+                float3 p2 = vertices[indices[i * 3 + 1]];
+                float3 p3 = vertices[indices[i * 3 + 2]];
+
+                volume += tetVolume(p0, p1, p2, p3); // compute the volume of the tetrahedron relative to the root vertice
+            }
+
+            return volume * (1.0f / 6.0f);
+        }
+
+        private static float tetVolume(float3 p0, float3 p1, float3 p2, float3 p3)
+        {
+            float3 a = p1 - p0;
+            float3 b = p2 - p0;
+            float3 c = p3 - p0;
+
+            float3 cross = float3.cross(b, c);
+            float volume = float3.dot(a, cross);
+
+            if (volume < 0f)
+                return -volume;
+            return volume;
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/ConvexBuilder.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/ConvexBuilder.cs
new file mode 100644
index 0000000..dfaede1
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/ConvexBuilder.cs
@@ -0,0 +1,411 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class DecompDesc
+    {
+        public List<float3> mVertices;
+        public List<int> mIndices;
+
+        // options
+        public uint mDepth; // depth to split, a maximum of 10, generally not over 7.
+        public float mCpercent; // the concavity threshold percentage. 0=20 is reasonable.
+        public float mPpercent; // the percentage volume conservation threshold to collapse hulls. 0-30 is reasonable.
+
+        // hull output limits.
+        public uint mMaxVertices; // maximum number of vertices in the output hull. Recommended 32 or less.
+        public float mSkinWidth; // a skin width to apply to the output hulls.
+
+        public ConvexDecompositionCallback mCallback; // the interface to receive back the results.
+
+        public DecompDesc()
+        {
+            mDepth = 5;
+            mCpercent = 5;
+            mPpercent = 5;
+            mMaxVertices = 32;
+        }
+    }
+
+    public class CHull
+    {
+        public float[] mMin = new float[3];
+        public float[] mMax = new float[3];
+        public float mVolume;
+        public float mDiagonal;
+        public ConvexResult mResult;
+
+        public CHull(ConvexResult result)
+        {
+            mResult = new ConvexResult(result);
+            mVolume = Concavity.computeMeshVolume(result.HullVertices, result.HullIndices);
+
+            mDiagonal = getBoundingRegion(result.HullVertices, mMin, mMax);
+
+            float dx = mMax[0] - mMin[0];
+            float dy = mMax[1] - mMin[1];
+            float dz = mMax[2] - mMin[2];
+
+            dx *= 0.1f; // inflate 1/10th on each edge
+            dy *= 0.1f; // inflate 1/10th on each edge
+            dz *= 0.1f; // inflate 1/10th on each edge
+
+            mMin[0] -= dx;
+            mMin[1] -= dy;
+            mMin[2] -= dz;
+
+            mMax[0] += dx;
+            mMax[1] += dy;
+            mMax[2] += dz;
+        }
+
+        public void Dispose()
+        {
+            mResult = null;
+        }
+
+        public bool overlap(CHull h)
+        {
+            return overlapAABB(mMin, mMax, h.mMin, h.mMax);
+        }
+
+        // returns the d1Giagonal distance
+        private static float getBoundingRegion(List<float3> points, float[] bmin, float[] bmax)
+        {
+            float3 first = points[0];
+
+            bmin[0] = first.x;
+            bmin[1] = first.y;
+            bmin[2] = first.z;
+
+            bmax[0] = first.x;
+            bmax[1] = first.y;
+            bmax[2] = first.z;
+
+            for (int i = 1; i < points.Count; i++)
+            {
+                float3 p = points[i];
+
+                if (p[0] < bmin[0]) bmin[0] = p[0];
+                if (p[1] < bmin[1]) bmin[1] = p[1];
+                if (p[2] < bmin[2]) bmin[2] = p[2];
+
+                if (p[0] > bmax[0]) bmax[0] = p[0];
+                if (p[1] > bmax[1]) bmax[1] = p[1];
+                if (p[2] > bmax[2]) bmax[2] = p[2];
+            }
+
+            float dx = bmax[0] - bmin[0];
+            float dy = bmax[1] - bmin[1];
+            float dz = bmax[2] - bmin[2];
+
+            return (float)Math.Sqrt(dx * dx + dy * dy + dz * dz);
+        }
+
+        // return true if the two AABB's overlap.
+        private static bool overlapAABB(float[] bmin1, float[] bmax1, float[] bmin2, float[] bmax2)
+        {
+            if (bmax2[0] < bmin1[0]) return false; // if the maximum is less than our minimum on any axis
+            if (bmax2[1] < bmin1[1]) return false;
+            if (bmax2[2] < bmin1[2]) return false;
+
+            if (bmin2[0] > bmax1[0]) return false; // if the minimum is greater than our maximum on any axis
+            if (bmin2[1] > bmax1[1]) return false; // if the minimum is greater than our maximum on any axis
+            if (bmin2[2] > bmax1[2]) return false; // if the minimum is greater than our maximum on any axis
+
+            return true; // the extents overlap
+        }
+    }
+
+    public class ConvexBuilder
+    {
+        public List<CHull> mChulls = new List<CHull>();
+        private ConvexDecompositionCallback mCallback;
+
+        private int MAXDEPTH = 8;
+        private float CONCAVE_PERCENT = 1f;
+        private float MERGE_PERCENT = 2f;
+
+        public ConvexBuilder(ConvexDecompositionCallback callback)
+        {
+            mCallback = callback;
+        }
+
+        public void Dispose()
+        {
+            int i;
+            for (i = 0; i < mChulls.Count; i++)
+            {
+                CHull cr = mChulls[i];
+                cr.Dispose();
+            }
+        }
+
+        public bool isDuplicate(uint i1, uint i2, uint i3, uint ci1, uint ci2, uint ci3)
+        {
+            uint dcount = 0;
+
+            Debug.Assert(i1 != i2 && i1 != i3 && i2 != i3);
+            Debug.Assert(ci1 != ci2 && ci1 != ci3 && ci2 != ci3);
+
+            if (i1 == ci1 || i1 == ci2 || i1 == ci3)
+                dcount++;
+            if (i2 == ci1 || i2 == ci2 || i2 == ci3)
+                dcount++;
+            if (i3 == ci1 || i3 == ci2 || i3 == ci3)
+                dcount++;
+
+            return dcount == 3;
+        }
+
+        public void getMesh(ConvexResult cr, VertexPool vc, List<int> indices)
+        {
+            List<int> src = cr.HullIndices;
+
+            for (int i = 0; i < src.Count / 3; i++)
+            {
+                int i1 = src[i * 3 + 0];
+                int i2 = src[i * 3 + 1];
+                int i3 = src[i * 3 + 2];
+
+                float3 p1 = cr.HullVertices[i1];
+                float3 p2 = cr.HullVertices[i2];
+                float3 p3 = cr.HullVertices[i3];
+
+                i1 = vc.getIndex(p1);
+                i2 = vc.getIndex(p2);
+                i3 = vc.getIndex(p3);
+            }
+        }
+
+        public CHull canMerge(CHull a, CHull b)
+        {
+            if (!a.overlap(b)) // if their AABB's (with a little slop) don't overlap, then return.
+                return null;
+
+            CHull ret = null;
+
+            // ok..we are going to combine both meshes into a single mesh
+            // and then we are going to compute the concavity...
+
+            VertexPool vc = new VertexPool();
+
+            List<int> indices = new List<int>();
+
+            getMesh(a.mResult, vc, indices);
+            getMesh(b.mResult, vc, indices);
+
+            int vcount = vc.GetSize();
+            List<float3> vertices = vc.GetVertices();
+            int tcount = indices.Count / 3;
+
+            //don't do anything if hull is empty
+            if (tcount == 0)
+            {
+                vc.Clear();
+                return null;
+            }
+
+            HullResult hresult = new HullResult();
+            HullDesc desc = new HullDesc();
+
+            desc.SetHullFlag(HullFlag.QF_TRIANGLES);
+            desc.Vertices = vertices;
+
+            HullError hret = HullUtils.CreateConvexHull(desc, ref hresult);
+
+            if (hret == HullError.QE_OK)
+            {
+                float combineVolume = Concavity.computeMeshVolume(hresult.OutputVertices, hresult.Indices);
+                float sumVolume = a.mVolume + b.mVolume;
+
+                float percent = (sumVolume * 100) / combineVolume;
+                if (percent >= (100.0f - MERGE_PERCENT))
+                {
+                    ConvexResult cr = new ConvexResult(hresult.OutputVertices, hresult.Indices);
+                    ret = new CHull(cr);
+                }
+            }
+
+            vc.Clear();
+            return ret;
+        }
+
+        public bool combineHulls()
+        {
+            bool combine = false;
+
+            sortChulls(mChulls); // sort the convex hulls, largest volume to least...
+
+            List<CHull> output = new List<CHull>(); // the output hulls...
+
+            int i;
+            for (i = 0; i < mChulls.Count && !combine; ++i)
+            {
+                CHull cr = mChulls[i];
+
+                int j;
+                for (j = 0; j < mChulls.Count; j++)
+                {
+                    CHull match = mChulls[j];
+
+                    if (cr != match) // don't try to merge a hull with itself, that be stoopid
+                    {
+
+                        CHull merge = canMerge(cr, match); // if we can merge these two....
+
+                        if (merge != null)
+                        {
+                            output.Add(merge);
+
+                            ++i;
+                            while (i != mChulls.Count)
+                            {
+                                CHull cr2 = mChulls[i];
+                                if (cr2 != match)
+                                {
+                                    output.Add(cr2);
+                                }
+                                i++;
+                            }
+
+                            cr.Dispose();
+                            match.Dispose();
+                            combine = true;
+                            break;
+                        }
+                    }
+                }
+
+                if (combine)
+                {
+                    break;
+                }
+                else
+                {
+                    output.Add(cr);
+                }
+            }
+
+            if (combine)
+            {
+                mChulls.Clear();
+                mChulls = output;
+                output.Clear();
+            }
+
+            return combine;
+        }
+
+        public int process(DecompDesc desc)
+        {
+            int ret = 0;
+
+            MAXDEPTH = (int)desc.mDepth;
+            CONCAVE_PERCENT = desc.mCpercent;
+            MERGE_PERCENT = desc.mPpercent;
+
+            ConvexDecomposition.calcConvexDecomposition(desc.mVertices, desc.mIndices, ConvexDecompResult, 0f, 0, MAXDEPTH, CONCAVE_PERCENT, MERGE_PERCENT);
+
+            while (combineHulls()) // keep combinging hulls until I can't combine any more...
+                ;
+
+            int i;
+            for (i = 0; i < mChulls.Count; i++)
+            {
+                CHull cr = mChulls[i];
+
+                // before we hand it back to the application, we need to regenerate the hull based on the
+                // limits given by the user.
+
+                ConvexResult c = cr.mResult; // the high resolution hull...
+
+                HullResult result = new HullResult();
+                HullDesc hdesc = new HullDesc();
+
+                hdesc.SetHullFlag(HullFlag.QF_TRIANGLES);
+
+                hdesc.Vertices = c.HullVertices;
+                hdesc.MaxVertices = desc.mMaxVertices; // maximum number of vertices allowed in the output
+
+                if (desc.mSkinWidth != 0f)
+                {
+                    hdesc.SkinWidth = desc.mSkinWidth;
+                    hdesc.SetHullFlag(HullFlag.QF_SKIN_WIDTH); // do skin width computation.
+                }
+
+                HullError ret2 = HullUtils.CreateConvexHull(hdesc, ref result);
+
+                if (ret2 == HullError.QE_OK)
+                {
+                    ConvexResult r = new ConvexResult(result.OutputVertices, result.Indices);
+
+                    r.mHullVolume = Concavity.computeMeshVolume(result.OutputVertices, result.Indices); // the volume of the hull.
+
+                    // compute the best fit OBB
+                    //computeBestFitOBB(result.mNumOutputVertices, result.mOutputVertices, sizeof(float) * 3, r.mOBBSides, r.mOBBTransform);
+
+                    //r.mOBBVolume = r.mOBBSides[0] * r.mOBBSides[1] * r.mOBBSides[2]; // compute the OBB volume.
+
+                    //fm_getTranslation(r.mOBBTransform, r.mOBBCenter); // get the translation component of the 4x4 matrix.
+
+                    //fm_matrixToQuat(r.mOBBTransform, r.mOBBOrientation); // extract the orientation as a quaternion.
+
+                    //r.mSphereRadius = computeBoundingSphere(result.mNumOutputVertices, result.mOutputVertices, r.mSphereCenter);
+                    //r.mSphereVolume = fm_sphereVolume(r.mSphereRadius);
+
+                    mCallback(r);
+                }
+
+                result = null;
+                cr.Dispose();
+            }
+
+            ret = mChulls.Count;
+
+            mChulls.Clear();
+
+            return ret;
+        }
+
+        public void ConvexDecompResult(ConvexResult result)
+        {
+            CHull ch = new CHull(result);
+            mChulls.Add(ch);
+        }
+
+        public void sortChulls(List<CHull> hulls)
+        {
+            hulls.Sort(delegate(CHull a, CHull b) { return a.mVolume.CompareTo(b.mVolume); });
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/ConvexDecomposition.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/ConvexDecomposition.cs
new file mode 100644
index 0000000..2e2bb70
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/ConvexDecomposition.cs
@@ -0,0 +1,200 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public delegate void ConvexDecompositionCallback(ConvexResult result);
+
+    public class FaceTri
+    {
+        public float3 P1;
+        public float3 P2;
+        public float3 P3;
+
+        public FaceTri() { }
+
+        public FaceTri(List<float3> vertices, int i1, int i2, int i3)
+        {
+            P1 = new float3(vertices[i1]);
+            P2 = new float3(vertices[i2]);
+            P3 = new float3(vertices[i3]);
+        }
+    }
+
+    public static class ConvexDecomposition
+    {
+        private static void addTri(VertexPool vl, List<int> list, float3 p1, float3 p2, float3 p3)
+        {
+            int i1 = vl.getIndex(p1);
+            int i2 = vl.getIndex(p2);
+            int i3 = vl.getIndex(p3);
+
+            // do *not* process degenerate triangles!
+            if ( i1 != i2 && i1 != i3 && i2 != i3 )
+            {
+                list.Add(i1);
+                list.Add(i2);
+                list.Add(i3);
+            }
+        }
+
+        public static void calcConvexDecomposition(List<float3> vertices, List<int> indices, ConvexDecompositionCallback callback, float masterVolume, int depth,
+            int maxDepth, float concavePercent, float mergePercent)
+        {
+            float4 plane = new float4();
+            bool split = false;
+
+            if (depth < maxDepth)
+            {
+                float volume = 0f;
+                float c = Concavity.computeConcavity(vertices, indices, ref plane, ref volume);
+
+                if (depth == 0)
+                {
+                    masterVolume = volume;
+                }
+
+                float percent = (c * 100.0f) / masterVolume;
+
+                if (percent > concavePercent) // if great than 5% of the total volume is concave, go ahead and keep splitting.
+                {
+                    split = true;
+                }
+            }
+
+            if (depth >= maxDepth || !split)
+            {
+                HullResult result = new HullResult();
+                HullDesc desc = new HullDesc();
+
+                desc.SetHullFlag(HullFlag.QF_TRIANGLES);
+
+                desc.Vertices = vertices;
+
+                HullError ret = HullUtils.CreateConvexHull(desc, ref result);
+
+                if (ret == HullError.QE_OK)
+                {
+                    ConvexResult r = new ConvexResult(result.OutputVertices, result.Indices);
+                    callback(r);
+                }
+
+                return;
+            }
+
+            List<int> ifront = new List<int>();
+            List<int> iback = new List<int>();
+
+            VertexPool vfront = new VertexPool();
+            VertexPool vback = new VertexPool();
+
+            // ok..now we are going to 'split' all of the input triangles against this plane!
+            for (int i = 0; i < indices.Count / 3; i++)
+            {
+                int i1 = indices[i * 3 + 0];
+                int i2 = indices[i * 3 + 1];
+                int i3 = indices[i * 3 + 2];
+
+                FaceTri t = new FaceTri(vertices, i1, i2, i3);
+
+                float3[] front = new float3[4];
+                float3[] back = new float3[4];
+
+                int fcount = 0;
+                int bcount = 0;
+
+                PlaneTriResult result = PlaneTri.planeTriIntersection(plane, t, 0.00001f, ref front, out fcount, ref back, out bcount);
+
+                if (fcount > 4 || bcount > 4)
+                {
+                    result = PlaneTri.planeTriIntersection(plane, t, 0.00001f, ref front, out fcount, ref back, out bcount);
+                }
+
+                switch (result)
+                {
+                    case PlaneTriResult.PTR_FRONT:
+                        Debug.Assert(fcount == 3);
+                        addTri(vfront, ifront, front[0], front[1], front[2]);
+                        break;
+                    case PlaneTriResult.PTR_BACK:
+                        Debug.Assert(bcount == 3);
+                        addTri(vback, iback, back[0], back[1], back[2]);
+                        break;
+                    case PlaneTriResult.PTR_SPLIT:
+                        Debug.Assert(fcount >= 3 && fcount <= 4);
+                        Debug.Assert(bcount >= 3 && bcount <= 4);
+
+                        addTri(vfront, ifront, front[0], front[1], front[2]);
+                        addTri(vback, iback, back[0], back[1], back[2]);
+
+                        if (fcount == 4)
+                        {
+                            addTri(vfront, ifront, front[0], front[2], front[3]);
+                        }
+
+                        if (bcount == 4)
+                        {
+                            addTri(vback, iback, back[0], back[2], back[3]);
+                        }
+
+                        break;
+                }
+            }
+
+            // ok... here we recursively call
+            if (ifront.Count > 0)
+            {
+                int vcount = vfront.GetSize();
+                List<float3> vertices2 = vfront.GetVertices();
+                for (int i = 0; i < vertices2.Count; i++)
+                    vertices2[i] = new float3(vertices2[i]);
+                int tcount = ifront.Count / 3;
+
+                calcConvexDecomposition(vertices2, ifront, callback, masterVolume, depth + 1, maxDepth, concavePercent, mergePercent);
+            }
+
+            ifront.Clear();
+            vfront.Clear();
+
+            if (iback.Count > 0)
+            {
+                int vcount = vback.GetSize();
+                List<float3> vertices2 = vback.GetVertices();
+                int tcount = iback.Count / 3;
+
+                calcConvexDecomposition(vertices2, iback, callback, masterVolume, depth + 1, maxDepth, concavePercent, mergePercent);
+            }
+
+            iback.Clear();
+            vback.Clear();
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/ConvexResult.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/ConvexResult.cs
new file mode 100644
index 0000000..87758b5
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/ConvexResult.cs
@@ -0,0 +1,74 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class ConvexResult
+    {
+        public List<float3> HullVertices;
+        public List<int> HullIndices;
+
+        public float mHullVolume; // the volume of the convex hull.
+
+        //public float[] OBBSides = new float[3]; // the width, height and breadth of the best fit OBB
+        //public float[] OBBCenter = new float[3]; // the center of the OBB
+        //public float[] OBBOrientation = new float[4]; // the quaternion rotation of the OBB.
+        //public float[] OBBTransform = new float[16]; // the 4x4 transform of the OBB.
+        //public float OBBVolume; // the volume of the OBB
+
+        //public float SphereRadius; // radius and center of best fit sphere
+        //public float[] SphereCenter = new float[3];
+        //public float SphereVolume; // volume of the best fit sphere
+
+        public ConvexResult()
+        {
+            HullVertices = new List<float3>();
+            HullIndices = new List<int>();
+        }
+
+        public ConvexResult(List<float3> hvertices, List<int> hindices)
+        {
+            HullVertices = hvertices;
+            HullIndices = hindices;
+        }
+
+        public ConvexResult(ConvexResult r)
+        {
+            HullVertices = new List<float3>(r.HullVertices);
+            HullIndices = new List<int>(r.HullIndices);
+        }
+
+        public void Dispose()
+        {
+            HullVertices = null;
+            HullIndices = null;
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/HullClasses.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/HullClasses.cs
new file mode 100644
index 0000000..d81df26
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/HullClasses.cs
@@ -0,0 +1,171 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class HullResult
+    {
+        public bool Polygons = true; // true if indices represents polygons, false indices are triangles
+        public List<float3> OutputVertices = new List<float3>();
+        public List<int> Indices;
+
+        // If triangles, then indices are array indexes into the vertex list.
+        // If polygons, indices are in the form (number of points in face) (p1, p2, p3, ..) etc..
+    }
+
+    public class PHullResult
+    {
+        public List<float3> Vertices = new List<float3>();
+        public List<int> Indices = new List<int>();
+    }
+
+    [Flags]
+    public enum HullFlag : int
+    {
+        QF_DEFAULT = 0,
+        QF_TRIANGLES = (1 << 0), // report results as triangles, not polygons.
+        QF_SKIN_WIDTH = (1 << 2) // extrude hull based on this skin width
+    }
+
+    public enum HullError : int
+    {
+        QE_OK, // success!
+        QE_FAIL // failed.
+    }
+
+    public class HullDesc
+    {
+        public HullFlag Flags; // flags to use when generating the convex hull.
+        public List<float3> Vertices;
+        public float NormalEpsilon; // the epsilon for removing duplicates. This is a normalized value, if normalized bit is on.
+        public float SkinWidth;
+        public uint MaxVertices; // maximum number of vertices to be considered for the hull!
+        public uint MaxFaces;
+
+        public HullDesc()
+        {
+            Flags = HullFlag.QF_DEFAULT;
+            Vertices = new List<float3>();
+            NormalEpsilon = 0.001f;
+            MaxVertices = 4096;
+            MaxFaces = 4096;
+            SkinWidth = 0.01f;
+        }
+
+        public HullDesc(HullFlag flags, List<float3> vertices)
+        {
+            Flags = flags;
+            Vertices = new List<float3>(vertices);
+            NormalEpsilon = 0.001f;
+            MaxVertices = 4096;
+            MaxFaces = 4096;
+            SkinWidth = 0.01f;
+        }
+
+        public bool HasHullFlag(HullFlag flag)
+        {
+            return (Flags & flag) != 0;
+        }
+
+        public void SetHullFlag(HullFlag flag)
+        {
+            Flags |= flag;
+        }
+
+        public void ClearHullFlag(HullFlag flag)
+        {
+            Flags &= ~flag;
+        }
+    }
+
+    public class ConvexH
+    {
+        public struct HalfEdge
+        {
+            public short ea; // the other half of the edge (index into edges list)
+            public byte v; // the vertex at the start of this edge (index into vertices list)
+            public byte p; // the facet on which this edge lies (index into facets list)
+
+            public HalfEdge(short _ea, byte _v, byte _p)
+            {
+                ea = _ea;
+                v = _v;
+                p = _p;
+            }
+
+            public HalfEdge(HalfEdge e)
+            {
+                ea = e.ea;
+                v = e.v;
+                p = e.p;
+            }
+        }
+
+        public List<float3> vertices = new List<float3>();
+        public List<HalfEdge> edges = new List<HalfEdge>();
+        public List<Plane> facets = new List<Plane>();
+
+        public ConvexH(int vertices_size, int edges_size, int facets_size)
+        {
+            vertices = new List<float3>(vertices_size);
+            edges = new List<HalfEdge>(edges_size);
+            facets = new List<Plane>(facets_size);
+        }
+    }
+
+    public class VertFlag
+    {
+        public byte planetest;
+        public byte junk;
+        public byte undermap;
+        public byte overmap;
+    }
+
+    public class EdgeFlag
+    {
+        public byte planetest;
+        public byte fixes;
+        public short undermap;
+        public short overmap;
+    }
+
+    public class PlaneFlag
+    {
+        public byte undermap;
+        public byte overmap;
+    }
+
+    public class Coplanar
+    {
+        public ushort ea;
+        public byte v0;
+        public byte v1;
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/HullTriangle.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/HullTriangle.cs
new file mode 100644
index 0000000..1119a75
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/HullTriangle.cs
@@ -0,0 +1,99 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class HullTriangle : int3
+    {
+        public int3 n = new int3();
+        public int id;
+        public int vmax;
+        public float rise;
+        private List<HullTriangle> tris;
+
+        public HullTriangle(int a, int b, int c, List<HullTriangle> tris)
+            : base(a, b, c)
+        {
+            this.tris = tris;
+
+            n = new int3(-1, -1, -1);
+            id = tris.Count;
+            tris.Add(this);
+            vmax = -1;
+            rise = 0.0f;
+        }
+
+        public void Dispose()
+        {
+            Debug.Assert(tris[id] == this);
+            tris[id] = null;
+        }
+
+        public int neib(int a, int b)
+        {
+            int i;
+
+            for (i = 0; i < 3; i++)
+            {
+                int i1 = (i + 1) % 3;
+                int i2 = (i + 2) % 3;
+                if ((this)[i] == a && (this)[i1] == b)
+                    return n[i2];
+                if ((this)[i] == b && (this)[i1] == a)
+                    return n[i2];
+            }
+
+            Debug.Assert(false);
+            return -1;
+        }
+
+        public void setneib(int a, int b, int value)
+        {
+            int i;
+
+            for (i = 0; i < 3; i++)
+            {
+                int i1 = (i + 1) % 3;
+                int i2 = (i + 2) % 3;
+                if ((this)[i] == a && (this)[i1] == b)
+                {
+                    n[i2] = value;
+                    return;
+                }
+                if ((this)[i] == b && (this)[i1] == a)
+                {
+                    n[i2] = value;
+                    return;
+                }
+            }
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/HullUtils.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/HullUtils.cs
new file mode 100644
index 0000000..c9ccfe2
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/HullUtils.cs
@@ -0,0 +1,1868 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public static class HullUtils
+    {
+        public static int argmin(float[] a, int n)
+        {
+            int r = 0;
+            for (int i = 1; i < n; i++)
+            {
+                if (a[i] < a[r])
+                {
+                    r = i;
+                }
+            }
+            return r;
+        }
+
+        public static float clampf(float a)
+        {
+            return Math.Min(1.0f, Math.Max(0.0f, a));
+        }
+
+        public static float Round(float a, float precision)
+        {
+            return (float)Math.Floor(0.5f + a / precision) * precision;
+        }
+
+        public static float Interpolate(float f0, float f1, float alpha)
+        {
+            return f0 * (1 - alpha) + f1 * alpha;
+        }
+
+        public static void Swap<T>(ref T a, ref T b)
+        {
+            T tmp = a;
+            a = b;
+            b = tmp;
+        }
+
+        public static bool above(List<float3> vertices, int3 t, float3 p, float epsilon)
+        {
+            float3 vtx = vertices[t.x];
+            float3 n = TriNormal(vtx, vertices[t.y], vertices[t.z]);
+            return (float3.dot(n, p - vtx) > epsilon); // EPSILON???
+        }
+
+        public static int hasedge(int3 t, int a, int b)
+        {
+            for (int i = 0; i < 3; i++)
+            {
+                int i1 = (i + 1) % 3;
+                if (t[i] == a && t[i1] == b)
+                    return 1;
+            }
+            return 0;
+        }
+
+        public static bool hasvert(int3 t, int v)
+        {
+            return (t[0] == v || t[1] == v || t[2] == v);
+        }
+
+        public static int shareedge(int3 a, int3 b)
+        {
+            int i;
+            for (i = 0; i < 3; i++)
+            {
+                int i1 = (i + 1) % 3;
+                if (hasedge(a, b[i1], b[i]) != 0)
+                    return 1;
+            }
+            return 0;
+        }
+
+        public static void b2bfix(HullTriangle s, HullTriangle t, List<HullTriangle> tris)
+        {
+            int i;
+            for (i = 0; i < 3; i++)
+            {
+                int i1 = (i + 1) % 3;
+                int i2 = (i + 2) % 3;
+                int a = (s)[i1];
+                int b = (s)[i2];
+                Debug.Assert(tris[s.neib(a, b)].neib(b, a) == s.id);
+                Debug.Assert(tris[t.neib(a, b)].neib(b, a) == t.id);
+                tris[s.neib(a, b)].setneib(b, a, t.neib(b, a));
+                tris[t.neib(b, a)].setneib(a, b, s.neib(a, b));
+            }
+        }
+
+        public static void removeb2b(HullTriangle s, HullTriangle t, List<HullTriangle> tris)
+        {
+            b2bfix(s, t, tris);
+            s.Dispose();
+            t.Dispose();
+        }
+
+        public static void checkit(HullTriangle t, List<HullTriangle> tris)
+        {
+            int i;
+            Debug.Assert(tris[t.id] == t);
+            for (i = 0; i < 3; i++)
+            {
+                int i1 = (i + 1) % 3;
+                int i2 = (i + 2) % 3;
+                int a = (t)[i1];
+                int b = (t)[i2];
+                Debug.Assert(a != b);
+                Debug.Assert(tris[t.n[i]].neib(b, a) == t.id);
+            }
+        }
+
+        public static void extrude(HullTriangle t0, int v, List<HullTriangle> tris)
+        {
+            int3 t = t0;
+            int n = tris.Count;
+            HullTriangle ta = new HullTriangle(v, t[1], t[2], tris);
+            ta.n = new int3(t0.n[0], n + 1, n + 2);
+            tris[t0.n[0]].setneib(t[1], t[2], n + 0);
+            HullTriangle tb = new HullTriangle(v, t[2], t[0], tris);
+            tb.n = new int3(t0.n[1], n + 2, n + 0);
+            tris[t0.n[1]].setneib(t[2], t[0], n + 1);
+            HullTriangle tc = new HullTriangle(v, t[0], t[1], tris);
+            tc.n = new int3(t0.n[2], n + 0, n + 1);
+            tris[t0.n[2]].setneib(t[0], t[1], n + 2);
+            checkit(ta, tris);
+            checkit(tb, tris);
+            checkit(tc, tris);
+            if (hasvert(tris[ta.n[0]], v))
+                removeb2b(ta, tris[ta.n[0]], tris);
+            if (hasvert(tris[tb.n[0]], v))
+                removeb2b(tb, tris[tb.n[0]], tris);
+            if (hasvert(tris[tc.n[0]], v))
+                removeb2b(tc, tris[tc.n[0]], tris);
+            t0.Dispose();
+        }
+
+        public static HullTriangle extrudable(float epsilon, List<HullTriangle> tris)
+        {
+            int i;
+            HullTriangle t = null;
+            for (i = 0; i < tris.Count; i++)
+            {
+                if (t == null || (tris.Count > i && (object)tris[i] != null && t.rise < tris[i].rise))
+                {
+                    t = tris[i];
+                }
+            }
+            return (t.rise > epsilon) ? t : null;
+        }
+
+        public static Quaternion RotationArc(float3 v0, float3 v1)
+        {
+            Quaternion q = new Quaternion();
+            v0 = float3.normalize(v0); // Comment these two lines out if you know its not needed.
+            v1 = float3.normalize(v1); // If vector is already unit length then why do it again?
+            float3 c = float3.cross(v0, v1);
+            float d = float3.dot(v0, v1);
+            if (d <= -1.0f) // 180 about x axis
+            {
+                return new Quaternion(1f, 0f, 0f, 0f);
+            }
+            float s = (float)Math.Sqrt((1 + d) * 2f);
+            q.x = c.x / s;
+            q.y = c.y / s;
+            q.z = c.z / s;
+            q.w = s / 2.0f;
+            return q;
+        }
+
+        public static float3 PlaneLineIntersection(Plane plane, float3 p0, float3 p1)
+        {
+            // returns the point where the line p0-p1 intersects the plane n&d
+            float3 dif = p1 - p0;
+            float dn = float3.dot(plane.normal, dif);
+            float t = -(plane.dist + float3.dot(plane.normal, p0)) / dn;
+            return p0 + (dif * t);
+        }
+
+        public static float3 LineProject(float3 p0, float3 p1, float3 a)
+        {
+            float3 w = new float3();
+            w = p1 - p0;
+            float t = float3.dot(w, (a - p0)) / (w.x * w.x + w.y * w.y + w.z * w.z);
+            return p0 + w * t;
+        }
+
+        public static float3 PlaneProject(Plane plane, float3 point)
+        {
+            return point - plane.normal * (float3.dot(point, plane.normal) + plane.dist);
+        }
+
+        public static float LineProjectTime(float3 p0, float3 p1, float3 a)
+        {
+            float3 w = new float3();
+            w = p1 - p0;
+            float t = float3.dot(w, (a - p0)) / (w.x * w.x + w.y * w.y + w.z * w.z);
+            return t;
+        }
+
+        public static float3 ThreePlaneIntersection(Plane p0, Plane p1, Plane p2)
+        {
+            float3x3 mp = float3x3.Transpose(new float3x3(p0.normal, p1.normal, p2.normal));
+            float3x3 mi = float3x3.Inverse(mp);
+            float3 b = new float3(p0.dist, p1.dist, p2.dist);
+            return -b * mi;
+        }
+
+        public static bool PolyHit(List<float3> vert, float3 v0, float3 v1)
+        {
+            float3 impact = new float3();
+            float3 normal = new float3();
+            return PolyHit(vert, v0, v1, out impact, out normal);
+        }
+
+        public static bool PolyHit(List<float3> vert, float3 v0, float3 v1, out float3 impact)
+        {
+            float3 normal = new float3();
+            return PolyHit(vert, v0, v1, out impact, out normal);
+        }
+
+        public static bool PolyHit(List<float3> vert, float3 v0, float3 v1, out float3 impact, out float3 normal)
+        {
+            float3 the_point = new float3();
+
+            impact = null;
+            normal = null;
+
+            int i;
+            float3 nrml = new float3(0, 0, 0);
+            for (i = 0; i < vert.Count; i++)
+            {
+                int i1 = (i + 1) % vert.Count;
+                int i2 = (i + 2) % vert.Count;
+                nrml = nrml + float3.cross(vert[i1] - vert[i], vert[i2] - vert[i1]);
+            }
+
+            float m = float3.magnitude(nrml);
+            if (m == 0.0)
+            {
+                return false;
+            }
+            nrml = nrml * (1.0f / m);
+            float dist = -float3.dot(nrml, vert[0]);
+            float d0;
+            float d1;
+            if ((d0 = float3.dot(v0, nrml) + dist) < 0 || (d1 = float3.dot(v1, nrml) + dist) > 0)
+            {
+                return false;
+            }
+
+            // By using the cached plane distances d0 and d1
+            // we can optimize the following:
+            //     the_point = planelineintersection(nrml,dist,v0,v1);
+            float a = d0 / (d0 - d1);
+            the_point = v0 * (1 - a) + v1 * a;
+
+
+            bool inside = true;
+            for (int j = 0; inside && j < vert.Count; j++)
+            {
+                // let inside = 0 if outside
+                float3 pp1 = new float3();
+                float3 pp2 = new float3();
+                float3 side = new float3();
+                pp1 = vert[j];
+                pp2 = vert[(j + 1) % vert.Count];
+                side = float3.cross((pp2 - pp1), (the_point - pp1));
+                inside = (float3.dot(nrml, side) >= 0.0);
+            }
+            if (inside)
+            {
+                if (normal != null)
+                {
+                    normal = nrml;
+                }
+                if (impact != null)
+                {
+                    impact = the_point;
+                }
+            }
+            return inside;
+        }
+
+        public static bool BoxInside(float3 p, float3 bmin, float3 bmax)
+        {
+            return (p.x >= bmin.x && p.x <= bmax.x && p.y >= bmin.y && p.y <= bmax.y && p.z >= bmin.z && p.z <= bmax.z);
+        }
+
+        public static bool BoxIntersect(float3 v0, float3 v1, float3 bmin, float3 bmax, float3 impact)
+        {
+            if (BoxInside(v0, bmin, bmax))
+            {
+                impact = v0;
+                return true;
+            }
+            if (v0.x <= bmin.x && v1.x >= bmin.x)
+            {
+                float a = (bmin.x - v0.x) / (v1.x - v0.x);
+                //v.x = bmin.x;
+                float vy = (1 - a) * v0.y + a * v1.y;
+                float vz = (1 - a) * v0.z + a * v1.z;
+                if (vy >= bmin.y && vy <= bmax.y && vz >= bmin.z && vz <= bmax.z)
+                {
+                    impact.x = bmin.x;
+                    impact.y = vy;
+                    impact.z = vz;
+                    return true;
+                }
+            }
+            else if (v0.x >= bmax.x && v1.x <= bmax.x)
+            {
+                float a = (bmax.x - v0.x) / (v1.x - v0.x);
+                //v.x = bmax.x;
+                float vy = (1 - a) * v0.y + a * v1.y;
+                float vz = (1 - a) * v0.z + a * v1.z;
+                if (vy >= bmin.y && vy <= bmax.y && vz >= bmin.z && vz <= bmax.z)
+                {
+                    impact.x = bmax.x;
+                    impact.y = vy;
+                    impact.z = vz;
+                    return true;
+                }
+            }
+            if (v0.y <= bmin.y && v1.y >= bmin.y)
+            {
+                float a = (bmin.y - v0.y) / (v1.y - v0.y);
+                float vx = (1 - a) * v0.x + a * v1.x;
+                //v.y = bmin.y;
+                float vz = (1 - a) * v0.z + a * v1.z;
+                if (vx >= bmin.x && vx <= bmax.x && vz >= bmin.z && vz <= bmax.z)
+                {
+                    impact.x = vx;
+                    impact.y = bmin.y;
+                    impact.z = vz;
+                    return true;
+                }
+            }
+            else if (v0.y >= bmax.y && v1.y <= bmax.y)
+            {
+                float a = (bmax.y - v0.y) / (v1.y - v0.y);
+                float vx = (1 - a) * v0.x + a * v1.x;
+                // vy = bmax.y;
+                float vz = (1 - a) * v0.z + a * v1.z;
+                if (vx >= bmin.x && vx <= bmax.x && vz >= bmin.z && vz <= bmax.z)
+                {
+                    impact.x = vx;
+                    impact.y = bmax.y;
+                    impact.z = vz;
+                    return true;
+                }
+            }
+            if (v0.z <= bmin.z && v1.z >= bmin.z)
+            {
+                float a = (bmin.z - v0.z) / (v1.z - v0.z);
+                float vx = (1 - a) * v0.x + a * v1.x;
+                float vy = (1 - a) * v0.y + a * v1.y;
+                // v.z = bmin.z;
+                if (vy >= bmin.y && vy <= bmax.y && vx >= bmin.x && vx <= bmax.x)
+                {
+                    impact.x = vx;
+                    impact.y = vy;
+                    impact.z = bmin.z;
+                    return true;
+                }
+            }
+            else if (v0.z >= bmax.z && v1.z <= bmax.z)
+            {
+                float a = (bmax.z - v0.z) / (v1.z - v0.z);
+                float vx = (1 - a) * v0.x + a * v1.x;
+                float vy = (1 - a) * v0.y + a * v1.y;
+                // v.z = bmax.z;
+                if (vy >= bmin.y && vy <= bmax.y && vx >= bmin.x && vx <= bmax.x)
+                {
+                    impact.x = vx;
+                    impact.y = vy;
+                    impact.z = bmax.z;
+                    return true;
+                }
+            }
+            return false;
+        }
+
+        public static float DistanceBetweenLines(float3 ustart, float3 udir, float3 vstart, float3 vdir, float3 upoint)
+        {
+            return DistanceBetweenLines(ustart, udir, vstart, vdir, upoint, null);
+        }
+
+        public static float DistanceBetweenLines(float3 ustart, float3 udir, float3 vstart, float3 vdir)
+        {
+            return DistanceBetweenLines(ustart, udir, vstart, vdir, null, null);
+        }
+
+        public static float DistanceBetweenLines(float3 ustart, float3 udir, float3 vstart, float3 vdir, float3 upoint, float3 vpoint)
+        {
+            float3 cp = float3.normalize(float3.cross(udir, vdir));
+
+            float distu = -float3.dot(cp, ustart);
+            float distv = -float3.dot(cp, vstart);
+            float dist = (float)Math.Abs(distu - distv);
+            if (upoint != null)
+            {
+                Plane plane = new Plane();
+                plane.normal = float3.normalize(float3.cross(vdir, cp));
+                plane.dist = -float3.dot(plane.normal, vstart);
+                upoint = PlaneLineIntersection(plane, ustart, ustart + udir);
+            }
+            if (vpoint != null)
+            {
+                Plane plane = new Plane();
+                plane.normal = float3.normalize(float3.cross(udir, cp));
+                plane.dist = -float3.dot(plane.normal, ustart);
+                vpoint = PlaneLineIntersection(plane, vstart, vstart + vdir);
+            }
+            return dist;
+        }
+
+        public static float3 TriNormal(float3 v0, float3 v1, float3 v2)
+        {
+            // return the normal of the triangle
+            // inscribed by v0, v1, and v2
+            float3 cp = float3.cross(v1 - v0, v2 - v1);
+            float m = float3.magnitude(cp);
+            if (m == 0)
+                return new float3(1, 0, 0);
+            return cp * (1.0f / m);
+        }
+
+        public static int PlaneTest(Plane p, float3 v, float planetestepsilon)
+        {
+            float a = float3.dot(v, p.normal) + p.dist;
+            int flag = (a > planetestepsilon) ? (2) : ((a < -planetestepsilon) ? (1) : (0));
+            return flag;
+        }
+
+        public static int SplitTest(ref ConvexH convex, Plane plane, float planetestepsilon)
+        {
+            int flag = 0;
+            for (int i = 0; i < convex.vertices.Count; i++)
+            {
+                flag |= PlaneTest(plane, convex.vertices[i], planetestepsilon);
+            }
+            return flag;
+        }
+
+        public static Quaternion VirtualTrackBall(float3 cop, float3 cor, float3 dir1, float3 dir2)
+        {
+            // routine taken from game programming gems.
+            // Implement track ball functionality to spin stuf on the screen
+            //  cop   center of projection
+            //  cor   center of rotation
+            //  dir1  old mouse direction
+            //  dir2  new mouse direction
+            // pretend there is a sphere around cor.  Then find the points
+            // where dir1 and dir2 intersect that sphere.  Find the
+            // rotation that takes the first point to the second.
+            float m;
+            // compute plane
+            float3 nrml = cor - cop;
+            float fudgefactor = 1.0f / (float3.magnitude(nrml) * 0.25f); // since trackball proportional to distance from cop
+            nrml = float3.normalize(nrml);
+            float dist = -float3.dot(nrml, cor);
+            float3 u = PlaneLineIntersection(new Plane(nrml, dist), cop, cop + dir1);
+            u = u - cor;
+            u = u * fudgefactor;
+            m = float3.magnitude(u);
+            if (m > 1)
+            {
+                u /= m;
+            }
+            else
+            {
+                u = u - (nrml * (float)Math.Sqrt(1 - m * m));
+            }
+            float3 v = PlaneLineIntersection(new Plane(nrml, dist), cop, cop + dir2);
+            v = v - cor;
+            v = v * fudgefactor;
+            m = float3.magnitude(v);
+            if (m > 1)
+            {
+                v /= m;
+            }
+            else
+            {
+                v = v - (nrml * (float)Math.Sqrt(1 - m * m));
+            }
+            return RotationArc(u, v);
+        }
+
+        public static bool AssertIntact(ConvexH convex, float planetestepsilon)
+        {
+            int i;
+            int estart = 0;
+            for (i = 0; i < convex.edges.Count; i++)
+            {
+                if (convex.edges[estart].p != convex.edges[i].p)
+                {
+                    estart = i;
+                }
+                int inext = i + 1;
+                if (inext >= convex.edges.Count || convex.edges[inext].p != convex.edges[i].p)
+                {
+                    inext = estart;
+                }
+                Debug.Assert(convex.edges[inext].p == convex.edges[i].p);
+                int nb = convex.edges[i].ea;
+                Debug.Assert(nb != 255);
+                if (nb == 255 || nb == -1)
+                    return false;
+                Debug.Assert(nb != -1);
+                Debug.Assert(i == convex.edges[nb].ea);
+            }
+            for (i = 0; i < convex.edges.Count; i++)
+            {
+                Debug.Assert((0) == PlaneTest(convex.facets[convex.edges[i].p], convex.vertices[convex.edges[i].v], planetestepsilon));
+                if ((0) != PlaneTest(convex.facets[convex.edges[i].p], convex.vertices[convex.edges[i].v], planetestepsilon))
+                    return false;
+                if (convex.edges[estart].p != convex.edges[i].p)
+                {
+                    estart = i;
+                }
+                int i1 = i + 1;
+                if (i1 >= convex.edges.Count || convex.edges[i1].p != convex.edges[i].p)
+                {
+                    i1 = estart;
+                }
+                int i2 = i1 + 1;
+                if (i2 >= convex.edges.Count || convex.edges[i2].p != convex.edges[i].p)
+                {
+                    i2 = estart;
+                }
+                if (i == i2) // i sliced tangent to an edge and created 2 meaningless edges
+                    continue;
+                float3 localnormal = TriNormal(convex.vertices[convex.edges[i].v], convex.vertices[convex.edges[i1].v], convex.vertices[convex.edges[i2].v]);
+                Debug.Assert(float3.dot(localnormal, convex.facets[convex.edges[i].p].normal) > 0);
+                if (float3.dot(localnormal, convex.facets[convex.edges[i].p].normal) <= 0)
+                    return false;
+            }
+            return true;
+        }
+
+        public static ConvexH test_btbq(float planetestepsilon)
+        {
+            // back to back quads
+            ConvexH convex = new ConvexH(4, 8, 2);
+            convex.vertices[0] = new float3(0, 0, 0);
+            convex.vertices[1] = new float3(1, 0, 0);
+            convex.vertices[2] = new float3(1, 1, 0);
+            convex.vertices[3] = new float3(0, 1, 0);
+            convex.facets[0] = new Plane(new float3(0, 0, 1), 0);
+            convex.facets[1] = new Plane(new float3(0, 0, -1), 0);
+            convex.edges[0] = new ConvexH.HalfEdge(7, 0, 0);
+            convex.edges[1] = new ConvexH.HalfEdge(6, 1, 0);
+            convex.edges[2] = new ConvexH.HalfEdge(5, 2, 0);
+            convex.edges[3] = new ConvexH.HalfEdge(4, 3, 0);
+
+            convex.edges[4] = new ConvexH.HalfEdge(3, 0, 1);
+            convex.edges[5] = new ConvexH.HalfEdge(2, 3, 1);
+            convex.edges[6] = new ConvexH.HalfEdge(1, 2, 1);
+            convex.edges[7] = new ConvexH.HalfEdge(0, 1, 1);
+            AssertIntact(convex, planetestepsilon);
+            return convex;
+        }
+
+        public static ConvexH test_cube()
+        {
+            ConvexH convex = new ConvexH(8, 24, 6);
+            convex.vertices[0] = new float3(0, 0, 0);
+            convex.vertices[1] = new float3(0, 0, 1);
+            convex.vertices[2] = new float3(0, 1, 0);
+            convex.vertices[3] = new float3(0, 1, 1);
+            convex.vertices[4] = new float3(1, 0, 0);
+            convex.vertices[5] = new float3(1, 0, 1);
+            convex.vertices[6] = new float3(1, 1, 0);
+            convex.vertices[7] = new float3(1, 1, 1);
+
+            convex.facets[0] = new Plane(new float3(-1, 0, 0), 0);
+            convex.facets[1] = new Plane(new float3(1, 0, 0), -1);
+            convex.facets[2] = new Plane(new float3(0, -1, 0), 0);
+            convex.facets[3] = new Plane(new float3(0, 1, 0), -1);
+            convex.facets[4] = new Plane(new float3(0, 0, -1), 0);
+            convex.facets[5] = new Plane(new float3(0, 0, 1), -1);
+
+            convex.edges[0] = new ConvexH.HalfEdge(11, 0, 0);
+            convex.edges[1] = new ConvexH.HalfEdge(23, 1, 0);
+            convex.edges[2] = new ConvexH.HalfEdge(15, 3, 0);
+            convex.edges[3] = new ConvexH.HalfEdge(16, 2, 0);
+
+            convex.edges[4] = new ConvexH.HalfEdge(13, 6, 1);
+            convex.edges[5] = new ConvexH.HalfEdge(21, 7, 1);
+            convex.edges[6] = new ConvexH.HalfEdge(9, 5, 1);
+            convex.edges[7] = new ConvexH.HalfEdge(18, 4, 1);
+
+            convex.edges[8] = new ConvexH.HalfEdge(19, 0, 2);
+            convex.edges[9] = new ConvexH.HalfEdge(6, 4, 2);
+            convex.edges[10] = new ConvexH.HalfEdge(20, 5, 2);
+            convex.edges[11] = new ConvexH.HalfEdge(0, 1, 2);
+
+            convex.edges[12] = new ConvexH.HalfEdge(22, 3, 3);
+            convex.edges[13] = new ConvexH.HalfEdge(4, 7, 3);
+            convex.edges[14] = new ConvexH.HalfEdge(17, 6, 3);
+            convex.edges[15] = new ConvexH.HalfEdge(2, 2, 3);
+
+            convex.edges[16] = new ConvexH.HalfEdge(3, 0, 4);
+            convex.edges[17] = new ConvexH.HalfEdge(14, 2, 4);
+            convex.edges[18] = new ConvexH.HalfEdge(7, 6, 4);
+            convex.edges[19] = new ConvexH.HalfEdge(8, 4, 4);
+
+            convex.edges[20] = new ConvexH.HalfEdge(10, 1, 5);
+            convex.edges[21] = new ConvexH.HalfEdge(5, 5, 5);
+            convex.edges[22] = new ConvexH.HalfEdge(12, 7, 5);
+            convex.edges[23] = new ConvexH.HalfEdge(1, 3, 5);
+
+            return convex;
+        }
+
+        public static ConvexH ConvexHMakeCube(float3 bmin, float3 bmax)
+        {
+            ConvexH convex = test_cube();
+            convex.vertices[0] = new float3(bmin.x, bmin.y, bmin.z);
+            convex.vertices[1] = new float3(bmin.x, bmin.y, bmax.z);
+            convex.vertices[2] = new float3(bmin.x, bmax.y, bmin.z);
+            convex.vertices[3] = new float3(bmin.x, bmax.y, bmax.z);
+            convex.vertices[4] = new float3(bmax.x, bmin.y, bmin.z);
+            convex.vertices[5] = new float3(bmax.x, bmin.y, bmax.z);
+            convex.vertices[6] = new float3(bmax.x, bmax.y, bmin.z);
+            convex.vertices[7] = new float3(bmax.x, bmax.y, bmax.z);
+
+            convex.facets[0] = new Plane(new float3(-1, 0, 0), bmin.x);
+            convex.facets[1] = new Plane(new float3(1, 0, 0), -bmax.x);
+            convex.facets[2] = new Plane(new float3(0, -1, 0), bmin.y);
+            convex.facets[3] = new Plane(new float3(0, 1, 0), -bmax.y);
+            convex.facets[4] = new Plane(new float3(0, 0, -1), bmin.z);
+            convex.facets[5] = new Plane(new float3(0, 0, 1), -bmax.z);
+            return convex;
+        }
+
+        public static ConvexH ConvexHCrop(ref ConvexH convex, Plane slice, float planetestepsilon)
+        {
+            int i;
+            int vertcountunder = 0;
+            int vertcountover = 0;
+            List<int> vertscoplanar = new List<int>(); // existing vertex members of convex that are coplanar
+            List<int> edgesplit = new List<int>(); // existing edges that members of convex that cross the splitplane
+
+            Debug.Assert(convex.edges.Count < 480);
+
+            EdgeFlag[] edgeflag = new EdgeFlag[512];
+            VertFlag[] vertflag = new VertFlag[256];
+            PlaneFlag[] planeflag = new PlaneFlag[128];
+            ConvexH.HalfEdge[] tmpunderedges = new ConvexH.HalfEdge[512];
+            Plane[] tmpunderplanes = new Plane[128];
+            Coplanar[] coplanaredges = new Coplanar[512];
+            int coplanaredges_num = 0;
+
+            List<float3> createdverts = new List<float3>();
+
+            // do the side-of-plane tests
+            for (i = 0; i < convex.vertices.Count; i++)
+            {
+                vertflag[i].planetest = (byte)PlaneTest(slice, convex.vertices[i], planetestepsilon);
+                if (vertflag[i].planetest == (0))
+                {
+                    // ? vertscoplanar.Add(i);
+                    vertflag[i].undermap = (byte)vertcountunder++;
+                    vertflag[i].overmap = (byte)vertcountover++;
+                }
+                else if (vertflag[i].planetest == (1))
+                {
+                    vertflag[i].undermap = (byte)vertcountunder++;
+                }
+                else
+                {
+                    Debug.Assert(vertflag[i].planetest == (2));
+                    vertflag[i].overmap = (byte)vertcountover++;
+                    vertflag[i].undermap = 255; // for debugging purposes
+                }
+            }
+            int vertcountunderold = vertcountunder; // for debugging only
+
+            int under_edge_count = 0;
+            int underplanescount = 0;
+            int e0 = 0;
+
+            for (int currentplane = 0; currentplane < convex.facets.Count; currentplane++)
+            {
+                int estart = e0;
+                int enextface = 0;
+                int planeside = 0;
+                int e1 = e0 + 1;
+                int vout = -1;
+                int vin = -1;
+                int coplanaredge = -1;
+                do
+                {
+
+                    if (e1 >= convex.edges.Count || convex.edges[e1].p != currentplane)
+                    {
+                        enextface = e1;
+                        e1 = estart;
+                    }
+                    ConvexH.HalfEdge edge0 = convex.edges[e0];
+                    ConvexH.HalfEdge edge1 = convex.edges[e1];
+                    ConvexH.HalfEdge edgea = convex.edges[edge0.ea];
+
+                    planeside |= vertflag[edge0.v].planetest;
+                    //if((vertflag[edge0.v].planetest & vertflag[edge1.v].planetest)  == COPLANAR) {
+                    //  assert(ecop==-1);
+                    //  ecop=e;
+                    //}
+
+                    if (vertflag[edge0.v].planetest == (2) && vertflag[edge1.v].planetest == (2))
+                    {
+                        // both endpoints over plane
+                        edgeflag[e0].undermap = -1;
+                    }
+                    else if ((vertflag[edge0.v].planetest | vertflag[edge1.v].planetest) == (1))
+                    {
+                        // at least one endpoint under, the other coplanar or under
+
+                        edgeflag[e0].undermap = (short)under_edge_count;
+                        tmpunderedges[under_edge_count].v = vertflag[edge0.v].undermap;
+                        tmpunderedges[under_edge_count].p = (byte)underplanescount;
+                        if (edge0.ea < e0)
+                        {
+                            // connect the neighbors
+                            Debug.Assert(edgeflag[edge0.ea].undermap != -1);
+                            tmpunderedges[under_edge_count].ea = edgeflag[edge0.ea].undermap;
+                            tmpunderedges[edgeflag[edge0.ea].undermap].ea = (short)under_edge_count;
+                        }
+                        under_edge_count++;
+                    }
+                    else if ((vertflag[edge0.v].planetest | vertflag[edge1.v].planetest) == (0))
+                    {
+                        // both endpoints coplanar 
+                        // must check a 3rd point to see if UNDER
+                        int e2 = e1 + 1;
+                        if (e2 >= convex.edges.Count || convex.edges[e2].p != currentplane)
+                        {
+                            e2 = estart;
+                        }
+                        Debug.Assert(convex.edges[e2].p == currentplane);
+                        ConvexH.HalfEdge edge2 = convex.edges[e2];
+                        if (vertflag[edge2.v].planetest == (1))
+                        {
+
+                            edgeflag[e0].undermap = (short)under_edge_count;
+                            tmpunderedges[under_edge_count].v = vertflag[edge0.v].undermap;
+                            tmpunderedges[under_edge_count].p = (byte)underplanescount;
+                            tmpunderedges[under_edge_count].ea = -1;
+                            // make sure this edge is added to the "coplanar" list
+                            coplanaredge = under_edge_count;
+                            vout = vertflag[edge0.v].undermap;
+                            vin = vertflag[edge1.v].undermap;
+                            under_edge_count++;
+                        }
+                        else
+                        {
+                            edgeflag[e0].undermap = -1;
+                        }
+                    }
+                    else if (vertflag[edge0.v].planetest == (1) && vertflag[edge1.v].planetest == (2))
+                    {
+                        // first is under 2nd is over 
+
+                        edgeflag[e0].undermap = (short)under_edge_count;
+                        tmpunderedges[under_edge_count].v = vertflag[edge0.v].undermap;
+                        tmpunderedges[under_edge_count].p = (byte)underplanescount;
+                        if (edge0.ea < e0)
+                        {
+                            Debug.Assert(edgeflag[edge0.ea].undermap != -1);
+                            // connect the neighbors
+                            tmpunderedges[under_edge_count].ea = edgeflag[edge0.ea].undermap;
+                            tmpunderedges[edgeflag[edge0.ea].undermap].ea = (short)under_edge_count;
+                            vout = tmpunderedges[edgeflag[edge0.ea].undermap].v;
+                        }
+                        else
+                        {
+                            Plane p0 = convex.facets[edge0.p];
+                            Plane pa = convex.facets[edgea.p];
+                            createdverts.Add(ThreePlaneIntersection(p0, pa, slice));
+                            //createdverts.Add(PlaneProject(slice,PlaneLineIntersection(slice,convex.vertices[edge0.v],convex.vertices[edgea.v])));
+                            //createdverts.Add(PlaneLineIntersection(slice,convex.vertices[edge0.v],convex.vertices[edgea.v]));
+                            vout = vertcountunder++;
+                        }
+                        under_edge_count++;
+                        /// hmmm something to think about: i might be able to output this edge regarless of 
+                        // wheter or not we know v-in yet.  ok i;ll try this now:
+                        tmpunderedges[under_edge_count].v = (byte)vout;
+                        tmpunderedges[under_edge_count].p = (byte)underplanescount;
+                        tmpunderedges[under_edge_count].ea = -1;
+                        coplanaredge = under_edge_count;
+                        under_edge_count++;
+
+                        if (vin != -1)
+                        {
+                            // we previously processed an edge  where we came under
+                            // now we know about vout as well
+
+                            // ADD THIS EDGE TO THE LIST OF EDGES THAT NEED NEIGHBOR ON PARTITION PLANE!!
+                        }
+
+                    }
+                    else if (vertflag[edge0.v].planetest == (0) && vertflag[edge1.v].planetest == (2))
+                    {
+                        // first is coplanar 2nd is over 
+
+                        edgeflag[e0].undermap = -1;
+                        vout = vertflag[edge0.v].undermap;
+                        // I hate this but i have to make sure part of this face is UNDER before ouputting this vert
+                        int k = estart;
+                        Debug.Assert(edge0.p == currentplane);
+                        while (!((planeside & 1) != 0) && k < convex.edges.Count && convex.edges[k].p == edge0.p)
+                        {
+                            planeside |= vertflag[convex.edges[k].v].planetest;
+                            k++;
+                        }
+                        if ((planeside & 1) != 0)
+                        {
+                            tmpunderedges[under_edge_count].v = (byte)vout;
+                            tmpunderedges[under_edge_count].p = (byte)underplanescount;
+                            tmpunderedges[under_edge_count].ea = -1;
+                            coplanaredge = under_edge_count; // hmmm should make a note of the edge # for later on
+                            under_edge_count++;
+
+                        }
+                    }
+                    else if (vertflag[edge0.v].planetest == (2) && vertflag[edge1.v].planetest == (1))
+                    {
+                        // first is over next is under 
+                        // new vertex!!!
+                        Debug.Assert(vin == -1);
+                        if (e0 < edge0.ea)
+                        {
+                            Plane p0 = convex.facets[edge0.p];
+                            Plane pa = convex.facets[edgea.p];
+                            createdverts.Add(ThreePlaneIntersection(p0, pa, slice));
+                            //createdverts.Add(PlaneLineIntersection(slice,convex.vertices[edge0.v],convex.vertices[edgea.v]));
+                            //createdverts.Add(PlaneProject(slice,PlaneLineIntersection(slice,convex.vertices[edge0.v],convex.vertices[edgea.v])));
+                            vin = vertcountunder++;
+                        }
+                        else
+                        {
+                            // find the new vertex that was created by edge[edge0.ea]
+                            int nea = edgeflag[edge0.ea].undermap;
+                            Debug.Assert(tmpunderedges[nea].p == tmpunderedges[nea + 1].p);
+                            vin = tmpunderedges[nea + 1].v;
+                            Debug.Assert(vin < vertcountunder);
+                            Debug.Assert(vin >= vertcountunderold); // for debugging only
+                        }
+                        if (vout != -1)
+                        {
+                            // we previously processed an edge  where we went over
+                            // now we know vin too
+                            // ADD THIS EDGE TO THE LIST OF EDGES THAT NEED NEIGHBOR ON PARTITION PLANE!!
+                        }
+                        // output edge
+                        tmpunderedges[under_edge_count].v = (byte)vin;
+                        tmpunderedges[under_edge_count].p = (byte)underplanescount;
+                        edgeflag[e0].undermap = (short)under_edge_count;
+                        if (e0 > edge0.ea)
+                        {
+                            Debug.Assert(edgeflag[edge0.ea].undermap != -1);
+                            // connect the neighbors
+                            tmpunderedges[under_edge_count].ea = edgeflag[edge0.ea].undermap;
+                            tmpunderedges[edgeflag[edge0.ea].undermap].ea = (short)under_edge_count;
+                        }
+                        Debug.Assert(edgeflag[e0].undermap == under_edge_count);
+                        under_edge_count++;
+                    }
+                    else if (vertflag[edge0.v].planetest == (2) && vertflag[edge1.v].planetest == (0))
+                    {
+                        // first is over next is coplanar 
+
+                        edgeflag[e0].undermap = -1;
+                        vin = vertflag[edge1.v].undermap;
+                        Debug.Assert(vin != -1);
+                        if (vout != -1)
+                        {
+                            // we previously processed an edge  where we came under
+                            // now we know both endpoints
+                            // ADD THIS EDGE TO THE LIST OF EDGES THAT NEED NEIGHBOR ON PARTITION PLANE!!
+                        }
+
+                    }
+                    else
+                    {
+                        Debug.Assert(false);
+                    }
+
+
+                    e0 = e1;
+                    e1++; // do the modulo at the beginning of the loop
+
+                } while (e0 != estart);
+                e0 = enextface;
+                if ((planeside & 1) != 0)
+                {
+                    planeflag[currentplane].undermap = (byte)underplanescount;
+                    tmpunderplanes[underplanescount] = convex.facets[currentplane];
+                    underplanescount++;
+                }
+                else
+                {
+                    planeflag[currentplane].undermap = 0;
+                }
+                if (vout >= 0 && (planeside & 1) != 0)
+                {
+                    Debug.Assert(vin >= 0);
+                    Debug.Assert(coplanaredge >= 0);
+                    Debug.Assert(coplanaredge != 511);
+                    coplanaredges[coplanaredges_num].ea = (ushort)coplanaredge;
+                    coplanaredges[coplanaredges_num].v0 = (byte)vin;
+                    coplanaredges[coplanaredges_num].v1 = (byte)vout;
+                    coplanaredges_num++;
+                }
+            }
+
+            // add the new plane to the mix:
+            if (coplanaredges_num > 0)
+            {
+                tmpunderplanes[underplanescount++] = slice;
+            }
+            for (i = 0; i < coplanaredges_num - 1; i++)
+            {
+                if (coplanaredges[i].v1 != coplanaredges[i + 1].v0)
+                {
+                    int j = 0;
+                    for (j = i + 2; j < coplanaredges_num; j++)
+                    {
+                        if (coplanaredges[i].v1 == coplanaredges[j].v0)
+                        {
+                            Coplanar tmp = coplanaredges[i + 1];
+                            coplanaredges[i + 1] = coplanaredges[j];
+                            coplanaredges[j] = tmp;
+                            break;
+                        }
+                    }
+                    if (j >= coplanaredges_num)
+                    {
+                        Debug.Assert(j < coplanaredges_num);
+                        return null;
+                    }
+                }
+            }
+
+            ConvexH punder = new ConvexH(vertcountunder, under_edge_count + coplanaredges_num, underplanescount);
+            ConvexH under = punder;
+
+            {
+                int k = 0;
+                for (i = 0; i < convex.vertices.Count; i++)
+                {
+                    if (vertflag[i].planetest != (2))
+                    {
+                        under.vertices[k++] = convex.vertices[i];
+                    }
+                }
+                i = 0;
+                while (k < vertcountunder)
+                {
+                    under.vertices[k++] = createdverts[i++];
+                }
+                Debug.Assert(i == createdverts.Count);
+            }
+
+            for (i = 0; i < coplanaredges_num; i++)
+            {
+                ConvexH.HalfEdge edge = under.edges[under_edge_count + i];
+                edge.p = (byte)(underplanescount - 1);
+                edge.ea = (short)coplanaredges[i].ea;
+                edge.v = (byte)coplanaredges[i].v0;
+                under.edges[under_edge_count + i] = edge;
+
+                tmpunderedges[coplanaredges[i].ea].ea = (short)(under_edge_count + i);
+            }
+
+            under.edges = new List<ConvexH.HalfEdge>(tmpunderedges);
+            under.facets = new List<Plane>(tmpunderplanes);
+            return punder;
+        }
+
+        public static ConvexH ConvexHDup(ConvexH src)
+        {
+            ConvexH dst = new ConvexH(src.vertices.Count, src.edges.Count, src.facets.Count);
+            dst.vertices = new List<float3>(src.vertices.Count);
+            foreach (float3 f in src.vertices)
+                dst.vertices.Add(new float3(f));
+            dst.edges = new List<ConvexH.HalfEdge>(src.edges.Count);
+            foreach (ConvexH.HalfEdge e in src.edges)
+                dst.edges.Add(new ConvexH.HalfEdge(e));
+            dst.facets = new List<Plane>(src.facets.Count);
+            foreach (Plane p in src.facets)
+                dst.facets.Add(new Plane(p));
+            return dst;
+        }
+
+        public static int candidateplane(List<Plane> planes, int planes_count, ConvexH convex, float epsilon)
+        {
+            int p = 0;
+            float md = 0;
+            int i;
+            for (i = 0; i < planes_count; i++)
+            {
+                float d = 0;
+                for (int j = 0; j < convex.vertices.Count; j++)
+                {
+                    d = Math.Max(d, float3.dot(convex.vertices[j], planes[i].normal) + planes[i].dist);
+                }
+                if (i == 0 || d > md)
+                {
+                    p = i;
+                    md = d;
+                }
+            }
+            return (md > epsilon) ? p : -1;
+        }
+
+        public static float3 orth(float3 v)
+        {
+            float3 a = float3.cross(v, new float3(0f, 0f, 1f));
+            float3 b = float3.cross(v, new float3(0f, 1f, 0f));
+            return float3.normalize((float3.magnitude(a) > float3.magnitude(b)) ? a : b);
+        }
+
+        public static int maxdir(List<float3> p, int count, float3 dir)
+        {
+            Debug.Assert(count != 0);
+            int m = 0;
+            float currDotm = float3.dot(p[0], dir);
+            for (int i = 1; i < count; i++)
+            {
+                float currDoti = float3.dot(p[i], dir);
+                if (currDoti > currDotm)
+                {
+                    currDotm = currDoti;
+                    m = i;
+                }
+            }
+            return m;
+        }
+
+        public static int maxdirfiltered(List<float3> p, int count, float3 dir, byte[] allow)
+        {
+            //Debug.Assert(count != 0);
+            int m = 0;
+            float currDotm = float3.dot(p[0], dir);
+            float currDoti;
+
+            while (allow[m] == 0)
+                m++;
+
+            for (int i = 1; i < count; i++)
+            {
+                if (allow[i] != 0)
+                {
+                    currDoti = float3.dot(p[i], dir);
+                    if (currDoti > currDotm)
+                    {
+                        currDotm = currDoti;
+                        m = i;
+                    }
+                }
+            }
+            //Debug.Assert(m != -1);
+            return m;
+        }
+
+        public static int maxdirsterid(List<float3> p, int count, float3 dir, byte[] allow)
+        {
+            int m = -1;
+            while (m == -1)
+            {
+                m = maxdirfiltered(p, count, dir, allow);
+                if (allow[m] == 3)
+                    return m;
+                float3 u = orth(dir);
+                float3 v = float3.cross(u, dir);
+                int ma = -1;
+                for (float x = 0.0f; x <= 360.0f; x += 45.0f)
+                {
+                    int mb;
+                    {
+                        float s = (float)Math.Sin((3.14159264f / 180.0f) * (x));
+                        float c = (float)Math.Cos((3.14159264f / 180.0f) * (x));
+                        mb = maxdirfiltered(p, count, dir + (u * s + v * c) * 0.025f, allow);
+                    }
+                    if (ma == m && mb == m)
+                    {
+                        allow[m] = 3;
+                        return m;
+                    }
+                    if (ma != -1 && ma != mb) // Yuck - this is really ugly
+                    {
+                        int mc = ma;
+                        for (float xx = x - 40.0f; xx <= x; xx += 5.0f)
+                        {
+                            float s = (float)Math.Sin((3.14159264f / 180.0f) * (xx));
+                            float c = (float)Math.Cos((3.14159264f / 180.0f) * (xx));
+                            int md = maxdirfiltered(p, count, dir + (u * s + v * c) * 0.025f, allow);
+                            if (mc == m && md == m)
+                            {
+                                allow[m] = 3;
+                                return m;
+                            }
+                            mc = md;
+                        }
+                    }
+                    ma = mb;
+                }
+                allow[m] = 0;
+                m = -1;
+            }
+
+            Debug.Assert(false);
+            return m;
+        }
+
+        public static int4 FindSimplex(List<float3> verts, byte[] allow)
+        {
+            float3[] basis = new float3[3];
+            basis[0] = new float3(0.01f, 0.02f, 1.0f);
+            int p0 = maxdirsterid(verts, verts.Count, basis[0], allow);
+            int p1 = maxdirsterid(verts, verts.Count, -basis[0], allow);
+            basis[0] = verts[p0] - verts[p1];
+            if (p0 == p1 || basis[0] == new float3(0, 0, 0))
+                return new int4(-1, -1, -1, -1);
+            basis[1] = float3.cross(new float3(1, 0.02f, 0), basis[0]);
+            basis[2] = float3.cross(new float3(-0.02f, 1, 0), basis[0]);
+            basis[1] = float3.normalize((float3.magnitude(basis[1]) > float3.magnitude(basis[2])) ? basis[1] : basis[2]);
+            int p2 = maxdirsterid(verts, verts.Count, basis[1], allow);
+            if (p2 == p0 || p2 == p1)
+            {
+                p2 = maxdirsterid(verts, verts.Count, -basis[1], allow);
+            }
+            if (p2 == p0 || p2 == p1)
+                return new int4(-1, -1, -1, -1);
+            basis[1] = verts[p2] - verts[p0];
+            basis[2] = float3.normalize(float3.cross(basis[1], basis[0]));
+            int p3 = maxdirsterid(verts, verts.Count, basis[2], allow);
+            if (p3 == p0 || p3 == p1 || p3 == p2)
+                p3 = maxdirsterid(verts, verts.Count, -basis[2], allow);
+            if (p3 == p0 || p3 == p1 || p3 == p2)
+                return new int4(-1, -1, -1, -1);
+            Debug.Assert(!(p0 == p1 || p0 == p2 || p0 == p3 || p1 == p2 || p1 == p3 || p2 == p3));
+            if (float3.dot(verts[p3] - verts[p0], float3.cross(verts[p1] - verts[p0], verts[p2] - verts[p0])) < 0)
+            {
+                Swap(ref p2, ref p3);
+            }
+            return new int4(p0, p1, p2, p3);
+        }
+
+        public static float GetDist(float px, float py, float pz, float3 p2)
+        {
+            float dx = px - p2.x;
+            float dy = py - p2.y;
+            float dz = pz - p2.z;
+
+            return dx * dx + dy * dy + dz * dz;
+        }
+
+        public static void ReleaseHull(PHullResult result)
+        {
+            if (result.Indices != null)
+                result.Indices = null;
+            if (result.Vertices != null)
+                result.Vertices = null;
+        }
+
+        public static int calchullgen(List<float3> verts, int vlimit, List<HullTriangle> tris)
+        {
+            if (verts.Count < 4)
+                return 0;
+            if (vlimit == 0)
+                vlimit = 1000000000;
+            int j;
+            float3 bmin = new float3(verts[0]);
+            float3 bmax = new float3(verts[0]);
+            List<int> isextreme = new List<int>(verts.Count);
+            byte[] allow = new byte[verts.Count];
+            for (j = 0; j < verts.Count; j++)
+            {
+                allow[j] = 1;
+                isextreme.Add(0);
+                bmin = float3.VectorMin(bmin, verts[j]);
+                bmax = float3.VectorMax(bmax, verts[j]);
+            }
+            float epsilon = float3.magnitude(bmax - bmin) * 0.001f;
+
+            int4 p = FindSimplex(verts, allow);
+            if (p.x == -1) // simplex failed
+                return 0;
+
+            float3 center = (verts[p[0]] + verts[p[1]] + verts[p[2]] + verts[p[3]]) / 4.0f; // a valid interior point
+            HullTriangle t0 = new HullTriangle(p[2], p[3], p[1], tris);
+            t0.n = new int3(2, 3, 1);
+            HullTriangle t1 = new HullTriangle(p[3], p[2], p[0], tris);
+            t1.n = new int3(3, 2, 0);
+            HullTriangle t2 = new HullTriangle(p[0], p[1], p[3], tris);
+            t2.n = new int3(0, 1, 3);
+            HullTriangle t3 = new HullTriangle(p[1], p[0], p[2], tris);
+            t3.n = new int3(1, 0, 2);
+            isextreme[p[0]] = isextreme[p[1]] = isextreme[p[2]] = isextreme[p[3]] = 1;
+            checkit(t0, tris);
+            checkit(t1, tris);
+            checkit(t2, tris);
+            checkit(t3, tris);
+
+            for (j = 0; j < tris.Count; j++)
+            {
+                HullTriangle t = tris[j];
+                Debug.Assert((object)t != null);
+                Debug.Assert(t.vmax < 0);
+                float3 n = TriNormal(verts[(t)[0]], verts[(t)[1]], verts[(t)[2]]);
+                t.vmax = maxdirsterid(verts, verts.Count, n, allow);
+                t.rise = float3.dot(n, verts[t.vmax] - verts[(t)[0]]);
+            }
+            HullTriangle te;
+            vlimit -= 4;
+            while (vlimit > 0 && (te = extrudable(epsilon, tris)) != null)
+            {
+                int3 ti = te;
+                int v = te.vmax;
+                Debug.Assert(isextreme[v] == 0); // wtf we've already done this vertex
+                isextreme[v] = 1;
+                //if(v==p0 || v==p1 || v==p2 || v==p3) continue; // done these already
+                j = tris.Count;
+                while (j-- != 0)
+                {
+                    if (tris.Count <= j || (object)tris[j] == null)
+                        continue;
+                    int3 t = tris[j];
+                    if (above(verts, t, verts[v], 0.01f * epsilon))
+                    {
+                        extrude(tris[j], v, tris);
+                    }
+                }
+                // now check for those degenerate cases where we have a flipped triangle or a really skinny triangle
+                j = tris.Count;
+                while (j-- != 0)
+                {
+                    if (tris.Count <= j || (object)tris[j] == null)
+                        continue;
+                    if (!hasvert(tris[j], v))
+                        break;
+                    int3 nt = tris[j];
+                    if (above(verts, nt, center, 0.01f * epsilon) || float3.magnitude(float3.cross(verts[nt[1]] - verts[nt[0]], verts[nt[2]] - verts[nt[1]])) < epsilon * epsilon * 0.1f)
+                    {
+                        HullTriangle nb = tris[tris[j].n[0]];
+                        Debug.Assert(nb != null);
+                        Debug.Assert(!hasvert(nb, v));
+                        Debug.Assert(nb.id < j);
+                        extrude(nb, v, tris);
+                        j = tris.Count;
+                    }
+                }
+                j = tris.Count;
+                while (j-- != 0)
+                {
+                    HullTriangle t = tris[j];
+                    if (t == null)
+                        continue;
+                    if (t.vmax >= 0)
+                        break;
+                    float3 n = TriNormal(verts[(t)[0]], verts[(t)[1]], verts[(t)[2]]);
+                    t.vmax = maxdirsterid(verts, verts.Count, n, allow);
+                    if (isextreme[t.vmax] != 0)
+                    {
+                        t.vmax = -1; // already done that vertex - algorithm needs to be able to terminate.
+                    }
+                    else
+                    {
+                        t.rise = float3.dot(n, verts[t.vmax] - verts[(t)[0]]);
+                    }
+                }
+                vlimit--;
+            }
+            return 1;
+        }
+
+        public static bool calchull(List<float3> verts, out List<int> tris_out, int vlimit, List<HullTriangle> tris)
+        {
+            tris_out = null;
+
+            int rc = calchullgen(verts, vlimit, tris);
+            if (rc == 0)
+                return false;
+            List<int> ts = new List<int>();
+            for (int i = 0; i < tris.Count; i++)
+            {
+                if ((object)tris[i] != null)
+                {
+                    for (int j = 0; j < 3; j++)
+                        ts.Add((tris[i])[j]);
+                    tris[i] = null;
+                }
+            }
+
+            tris_out = ts;
+            tris.Clear();
+            return true;
+        }
+
+        public static int calchullpbev(List<float3> verts, int vlimit, out List<Plane> planes, float bevangle, List<HullTriangle> tris)
+        {
+            int i;
+            int j;
+            planes = new List<Plane>();
+            int rc = calchullgen(verts, vlimit, tris);
+            if (rc == 0)
+                return 0;
+            for (i = 0; i < tris.Count; i++)
+            {
+                if (tris[i] != null)
+                {
+                    Plane p = new Plane();
+                    HullTriangle t = tris[i];
+                    p.normal = TriNormal(verts[(t)[0]], verts[(t)[1]], verts[(t)[2]]);
+                    p.dist = -float3.dot(p.normal, verts[(t)[0]]);
+                    planes.Add(p);
+                    for (j = 0; j < 3; j++)
+                    {
+                        if (t.n[j] < t.id)
+                            continue;
+                        HullTriangle s = tris[t.n[j]];
+                        float3 snormal = TriNormal(verts[(s)[0]], verts[(s)[1]], verts[(s)[2]]);
+                        if (float3.dot(snormal, p.normal) >= Math.Cos(bevangle * (3.14159264f / 180.0f)))
+                            continue;
+                        float3 n = float3.normalize(snormal + p.normal);
+                        planes.Add(new Plane(n, -float3.dot(n, verts[maxdir(verts, verts.Count, n)])));
+                    }
+                }
+            }
+
+            tris.Clear();
+            return 1;
+        }
+
+        public static int overhull(List<Plane> planes, List<float3> verts, int maxplanes, out List<float3> verts_out, out List<int> faces_out, float inflate)
+        {
+            verts_out = null;
+            faces_out = null;
+
+            int i;
+            int j;
+            if (verts.Count < 4)
+                return 0;
+            maxplanes = Math.Min(maxplanes, planes.Count);
+            float3 bmin = new float3(verts[0]);
+            float3 bmax = new float3(verts[0]);
+            for (i = 0; i < verts.Count; i++)
+            {
+                bmin = float3.VectorMin(bmin, verts[i]);
+                bmax = float3.VectorMax(bmax, verts[i]);
+            }
+            //  float diameter = magnitude(bmax-bmin);
+            //  inflate *=diameter;   // RELATIVE INFLATION
+            bmin -= new float3(inflate, inflate, inflate);
+            bmax += new float3(inflate, inflate, inflate);
+            for (i = 0; i < planes.Count; i++)
+            {
+                planes[i].dist -= inflate;
+            }
+            float3 emin = new float3(bmin);
+            float3 emax = new float3(bmax);
+            float epsilon = float3.magnitude(emax - emin) * 0.025f;
+            float planetestepsilon = float3.magnitude(emax - emin) * (0.001f);
+            // todo: add bounding cube planes to force bevel. or try instead not adding the diameter expansion ??? must think.
+            // ConvexH *convex = ConvexHMakeCube(bmin - float3(diameter,diameter,diameter),bmax+float3(diameter,diameter,diameter));
+            ConvexH c = ConvexHMakeCube(new float3(bmin), new float3(bmax));
+            int k;
+            while (maxplanes-- != 0 && (k = candidateplane(planes, planes.Count, c, epsilon)) >= 0)
+            {
+                ConvexH tmp = c;
+                c = ConvexHCrop(ref tmp, planes[k], planetestepsilon);
+                if (c == null) // might want to debug this case better!!!
+                {
+                    c = tmp;
+                    break;
+                }
+                if (AssertIntact(c, planetestepsilon) == false) // might want to debug this case better too!!!
+                {
+                    c = tmp;
+                    break;
+                }
+                tmp.edges = null;
+                tmp.facets = null;
+                tmp.vertices = null;
+            }
+
+            Debug.Assert(AssertIntact(c, planetestepsilon));
+            //return c;
+            //C++ TO C# CONVERTER TODO TASK: The memory management function 'malloc' has no equivalent in C#:
+            faces_out = new List<int>(); //(int)malloc(sizeof(int) * (1 + c.facets.Count + c.edges.Count)); // new int[1+c->facets.count+c->edges.count];
+            int faces_count_out = 0;
+            i = 0;
+            faces_out[faces_count_out++] = -1;
+            k = 0;
+            while (i < c.edges.Count)
+            {
+                j = 1;
+                while (j + i < c.edges.Count && c.edges[i].p == c.edges[i + j].p)
+                {
+                    j++;
+                }
+                faces_out[faces_count_out++] = j;
+                while (j-- != 0)
+                {
+                    faces_out[faces_count_out++] = c.edges[i].v;
+                    i++;
+                }
+                k++;
+            }
+            faces_out[0] = k; // number of faces.
+            Debug.Assert(k == c.facets.Count);
+            Debug.Assert(faces_count_out == 1 + c.facets.Count + c.edges.Count);
+            verts_out = c.vertices; // new float3[c->vertices.count];
+            int verts_count_out = c.vertices.Count;
+            for (i = 0; i < c.vertices.Count; i++)
+            {
+                verts_out[i] = new float3(c.vertices[i]);
+            }
+
+            c.edges = null;
+            c.facets = null;
+            c.vertices = null;
+            return 1;
+        }
+
+        public static int overhullv(List<float3> verts, int maxplanes, out List<float3> verts_out, out List<int> faces_out, float inflate, float bevangle, int vlimit, List<HullTriangle> tris)
+        {
+            verts_out = null;
+            faces_out = null;
+
+            if (verts.Count == 0)
+                return 0;
+            List<Plane> planes = new List<Plane>();
+            int rc = calchullpbev(verts, vlimit, out planes, bevangle, tris);
+            if (rc == 0)
+                return 0;
+            return overhull(planes, verts, maxplanes, out verts_out, out faces_out, inflate);
+        }
+
+        public static void addPoint(ref uint vcount, List<float3> p, float x, float y, float z)
+        {
+            p.Add(new float3(x, y, z));
+            vcount++;
+        }
+
+        public static bool ComputeHull(List<float3> vertices, ref PHullResult result, int vlimit, float inflate)
+        {
+            List<HullTriangle> tris = new List<HullTriangle>();
+            List<int> faces;
+            List<float3> verts_out;
+
+            if (inflate == 0.0f)
+            {
+                List<int> tris_out;
+                bool ret = calchull(vertices, out tris_out, vlimit, tris);
+                if (ret == false)
+                    return false;
+
+                result.Indices = tris_out;
+                result.Vertices = vertices;
+                return true;
+            }
+            else
+            {
+                int ret = overhullv(vertices, 35, out verts_out, out faces, inflate, 120.0f, vlimit, tris);
+                if (ret == 0)
+                    return false;
+
+                List<int3> tris2 = new List<int3>();
+                int n = faces[0];
+                int k = 1;
+                for (int i = 0; i < n; i++)
+                {
+                    int pn = faces[k++];
+                    for (int j = 2; j < pn; j++)
+                        tris2.Add(new int3(faces[k], faces[k + j - 1], faces[k + j]));
+                    k += pn;
+                }
+                Debug.Assert(tris2.Count == faces.Count - 1 - (n * 3));
+
+                result.Indices = new List<int>(tris2.Count * 3);
+                for (int i = 0; i < tris2.Count; i++)
+                {
+                    result.Indices.Add(tris2[i].x);
+                    result.Indices.Add(tris2[i].y);
+                    result.Indices.Add(tris2[i].z);
+                }
+                result.Vertices = verts_out;
+
+                return true;
+            }
+        }
+
+        private static bool CleanupVertices(List<float3> svertices, out List<float3> vertices, float normalepsilon, out float3 scale)
+        {
+            const float EPSILON = 0.000001f;
+
+            vertices = new List<float3>();
+            scale = new float3(1f, 1f, 1f);
+
+            if (svertices.Count == 0)
+                return false;
+
+            uint vcount = 0;
+
+            float[] recip = new float[3];
+
+            float[] bmin = { Single.MaxValue, Single.MaxValue, Single.MaxValue };
+            float[] bmax = { Single.MinValue, Single.MinValue, Single.MinValue };
+
+            for (int i = 0; i < svertices.Count; i++)
+            {
+                float3 p = svertices[i];
+
+                for (int j = 0; j < 3; j++)
+                {
+                    if (p[j] < bmin[j])
+                        bmin[j] = p[j];
+                    if (p[j] > bmax[j])
+                        bmax[j] = p[j];
+                }
+            }
+
+            float dx = bmax[0] - bmin[0];
+            float dy = bmax[1] - bmin[1];
+            float dz = bmax[2] - bmin[2];
+
+            float3 center = new float3();
+
+            center.x = dx * 0.5f + bmin[0];
+            center.y = dy * 0.5f + bmin[1];
+            center.z = dz * 0.5f + bmin[2];
+
+            if (dx < EPSILON || dy < EPSILON || dz < EPSILON || svertices.Count < 3)
+            {
+                float len = Single.MaxValue;
+
+                if (dx > EPSILON && dx < len)
+                    len = dx;
+                if (dy > EPSILON && dy < len)
+                    len = dy;
+                if (dz > EPSILON && dz < len)
+                    len = dz;
+
+                if (len == Single.MaxValue)
+                {
+                    dx = dy = dz = 0.01f; // one centimeter
+                }
+                else
+                {
+                    if (dx < EPSILON) // 1/5th the shortest non-zero edge.
+                        dx = len * 0.05f;
+                    if (dy < EPSILON)
+                        dy = len * 0.05f;
+                    if (dz < EPSILON)
+                        dz = len * 0.05f;
+                }
+
+                float x1 = center[0] - dx;
+                float x2 = center[0] + dx;
+
+                float y1 = center[1] - dy;
+                float y2 = center[1] + dy;
+
+                float z1 = center[2] - dz;
+                float z2 = center[2] + dz;
+
+                addPoint(ref vcount, vertices, x1, y1, z1);
+                addPoint(ref vcount, vertices, x2, y1, z1);
+                addPoint(ref vcount, vertices, x2, y2, z1);
+                addPoint(ref vcount, vertices, x1, y2, z1);
+                addPoint(ref vcount, vertices, x1, y1, z2);
+                addPoint(ref vcount, vertices, x2, y1, z2);
+                addPoint(ref vcount, vertices, x2, y2, z2);
+                addPoint(ref vcount, vertices, x1, y2, z2);
+
+                return true; // return cube     
+            }
+            else
+            {
+                scale.x = dx;
+                scale.y = dy;
+                scale.z = dz;
+
+                recip[0] = 1f / dx;
+                recip[1] = 1f / dy;
+                recip[2] = 1f / dz;
+
+                center.x *= recip[0];
+                center.y *= recip[1];
+                center.z *= recip[2];
+            }
+
+            for (int i = 0; i < svertices.Count; i++)
+            {
+                float3 p = svertices[i];
+
+                float px = p[0];
+                float py = p[1];
+                float pz = p[2];
+
+                px = px * recip[0]; // normalize
+                py = py * recip[1]; // normalize
+                pz = pz * recip[2]; // normalize
+
+                if (true)
+                {
+                    int j;
+
+                    for (j = 0; j < vcount; j++)
+                    {
+                        float3 v = vertices[j];
+
+                        float x = v[0];
+                        float y = v[1];
+                        float z = v[2];
+
+                        float dx1 = Math.Abs(x - px);
+                        float dy1 = Math.Abs(y - py);
+                        float dz1 = Math.Abs(z - pz);
+
+                        if (dx1 < normalepsilon && dy1 < normalepsilon && dz1 < normalepsilon)
+                        {
+                            // ok, it is close enough to the old one
+                            // now let us see if it is further from the center of the point cloud than the one we already recorded.
+                            // in which case we keep this one instead.
+                            float dist1 = GetDist(px, py, pz, center);
+                            float dist2 = GetDist(v[0], v[1], v[2], center);
+
+                            if (dist1 > dist2)
+                            {
+                                v.x = px;
+                                v.y = py;
+                                v.z = pz;
+                            }
+
+                            break;
+                        }
+                    }
+
+                    if (j == vcount)
+                    {
+                        float3 dest = new float3(px, py, pz);
+                        vertices.Add(dest);
+                        vcount++;
+                    }
+                }
+            }
+
+            // ok..now make sure we didn't prune so many vertices it is now invalid.
+            if (true)
+            {
+                float[] bmin2 = { Single.MaxValue, Single.MaxValue, Single.MaxValue };
+                float[] bmax2 = { Single.MinValue, Single.MinValue, Single.MinValue };
+
+                for (int i = 0; i < vcount; i++)
+                {
+                    float3 p = vertices[i];
+                    for (int j = 0; j < 3; j++)
+                    {
+                        if (p[j] < bmin2[j])
+                            bmin2[j] = p[j];
+                        if (p[j] > bmax2[j])
+                            bmax2[j] = p[j];
+                    }
+                }
+
+                float dx2 = bmax2[0] - bmin2[0];
+                float dy2 = bmax2[1] - bmin2[1];
+                float dz2 = bmax2[2] - bmin2[2];
+
+                if (dx2 < EPSILON || dy2 < EPSILON || dz2 < EPSILON || vcount < 3)
+                {
+                    float cx = dx2 * 0.5f + bmin2[0];
+                    float cy = dy2 * 0.5f + bmin2[1];
+                    float cz = dz2 * 0.5f + bmin2[2];
+
+                    float len = Single.MaxValue;
+
+                    if (dx2 >= EPSILON && dx2 < len)
+                        len = dx2;
+                    if (dy2 >= EPSILON && dy2 < len)
+                        len = dy2;
+                    if (dz2 >= EPSILON && dz2 < len)
+                        len = dz2;
+
+                    if (len == Single.MaxValue)
+                    {
+                        dx2 = dy2 = dz2 = 0.01f; // one centimeter
+                    }
+                    else
+                    {
+                        if (dx2 < EPSILON) // 1/5th the shortest non-zero edge.
+                            dx2 = len * 0.05f;
+                        if (dy2 < EPSILON)
+                            dy2 = len * 0.05f;
+                        if (dz2 < EPSILON)
+                            dz2 = len * 0.05f;
+                    }
+
+                    float x1 = cx - dx2;
+                    float x2 = cx + dx2;
+
+                    float y1 = cy - dy2;
+                    float y2 = cy + dy2;
+
+                    float z1 = cz - dz2;
+                    float z2 = cz + dz2;
+
+                    vcount = 0; // add box
+
+                    addPoint(ref vcount, vertices, x1, y1, z1);
+                    addPoint(ref vcount, vertices, x2, y1, z1);
+                    addPoint(ref vcount, vertices, x2, y2, z1);
+                    addPoint(ref vcount, vertices, x1, y2, z1);
+                    addPoint(ref vcount, vertices, x1, y1, z2);
+                    addPoint(ref vcount, vertices, x2, y1, z2);
+                    addPoint(ref vcount, vertices, x2, y2, z2);
+                    addPoint(ref vcount, vertices, x1, y2, z2);
+
+                    return true;
+                }
+            }
+
+            return true;
+        }
+
+        private static void BringOutYourDead(List<float3> verts, out List<float3> overts, List<int> indices)
+        {
+            int[] used = new int[verts.Count];
+            int ocount = 0;
+
+            overts = new List<float3>();
+
+            for (int i = 0; i < indices.Count; i++)
+            {
+                int v = indices[i]; // original array index
+
+                Debug.Assert(v >= 0 && v < verts.Count);
+
+                if (used[v] != 0) // if already remapped
+                {
+                    indices[i] = used[v] - 1; // index to new array
+                }
+                else
+                {
+                    indices[i] = ocount; // new index mapping
+
+                    overts.Add(verts[v]); // copy old vert to new vert array
+
+                    ocount++; // increment output vert count
+
+                    Debug.Assert(ocount >= 0 && ocount <= verts.Count);
+
+                    used[v] = ocount; // assign new index remapping
+                }
+            }
+        }
+
+        public static HullError CreateConvexHull(HullDesc desc, ref HullResult result)
+        {
+            HullError ret = HullError.QE_FAIL;
+
+            PHullResult hr = new PHullResult();
+
+            uint vcount = (uint)desc.Vertices.Count;
+            if (vcount < 8)
+                vcount = 8;
+
+            List<float3> vsource;
+            float3 scale = new float3();
+
+            bool ok = CleanupVertices(desc.Vertices, out vsource, desc.NormalEpsilon, out scale); // normalize point cloud, remove duplicates!
+
+            if (ok)
+            {
+                if (true) // scale vertices back to their original size.
+                {
+                    for (int i = 0; i < vsource.Count; i++)
+                    {
+                        float3 v = vsource[i];
+                        v.x *= scale[0];
+                        v.y *= scale[1];
+                        v.z *= scale[2];
+                    }
+                }
+
+                float skinwidth = 0;
+                if (desc.HasHullFlag(HullFlag.QF_SKIN_WIDTH))
+                    skinwidth = desc.SkinWidth;
+
+                ok = ComputeHull(vsource, ref hr, (int)desc.MaxVertices, skinwidth);
+
+                if (ok)
+                {
+                    List<float3> vscratch;
+                    BringOutYourDead(hr.Vertices, out vscratch, hr.Indices);
+
+                    ret = HullError.QE_OK;
+
+                    if (desc.HasHullFlag(HullFlag.QF_TRIANGLES)) // if he wants the results as triangle!
+                    {
+                        result.Polygons = false;
+                        result.Indices = hr.Indices;
+                        result.OutputVertices = vscratch;
+                    }
+                    else
+                    {
+                        result.Polygons = true;
+                        result.OutputVertices = vscratch;
+
+                        if (true)
+                        {
+                            List<int> source = hr.Indices;
+                            List<int> dest = new List<int>();
+                            for (int i = 0; i < hr.Indices.Count / 3; i++)
+                            {
+                                dest.Add(3);
+                                dest.Add(source[i * 3 + 0]);
+                                dest.Add(source[i * 3 + 1]);
+                                dest.Add(source[i * 3 + 2]);
+                            }
+
+                            result.Indices = dest;
+                        }
+                    }
+                }
+            }
+
+            return ret;
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/LICENSE.txt b/OpenSim/Region/Physics/ConvexDecompositionDotNet/LICENSE.txt
new file mode 100644
index 0000000..714ae89
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/LICENSE.txt
@@ -0,0 +1,28 @@
+ConvexDecompositionDotNet
+-------------------------
+
+The MIT License
+
+Copyright (c) 2010 Intel Corporation.
+All rights reserved.
+
+Based on the convexdecomposition library from 
+<http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/Plane.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/Plane.cs
new file mode 100644
index 0000000..d099676
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/Plane.cs
@@ -0,0 +1,99 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class Plane
+    {
+        public float3 normal = new float3();
+        public float dist; // distance below origin - the D from plane equasion Ax+By+Cz+D=0
+
+        public Plane(float3 n, float d)
+        {
+            normal = new float3(n);
+            dist = d;
+        }
+
+        public Plane(Plane p)
+        {
+            normal = new float3(p.normal);
+            dist = p.dist;
+        }
+
+        public Plane()
+        {
+            dist = 0;
+        }
+
+        public void Transform(float3 position, Quaternion orientation)
+        {
+            //   Transforms the plane to the space defined by the
+            //   given position/orientation
+            float3 newNormal = Quaternion.Inverse(orientation) * normal;
+            float3 origin = Quaternion.Inverse(orientation) * (-normal * dist - position);
+
+            normal = newNormal;
+            dist = -float3.dot(newNormal, origin);
+        }
+
+        public override int GetHashCode()
+        {
+            return normal.GetHashCode() ^ dist.GetHashCode();
+        }
+
+        public override bool Equals(object obj)
+        {
+            Plane p = obj as Plane;
+            if (p == null)
+                return false;
+
+            return this == p;
+        }
+
+        public static bool operator ==(Plane a, Plane b)
+        {
+            return (a.normal == b.normal && a.dist == b.dist);
+        }
+
+        public static bool operator !=(Plane a, Plane b)
+        {
+            return !(a == b);
+        }
+
+        public static Plane PlaneFlip(Plane plane)
+        {
+            return new Plane(-plane.normal, -plane.dist);
+        }
+
+        public static bool coplanar(Plane a, Plane b)
+        {
+            return (a == b || a == PlaneFlip(b));
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/PlaneTri.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/PlaneTri.cs
new file mode 100644
index 0000000..31f0182
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/PlaneTri.cs
@@ -0,0 +1,211 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public enum PlaneTriResult : int
+    {
+        PTR_FRONT,
+        PTR_BACK,
+        PTR_SPLIT
+    }
+
+    public static class PlaneTri
+    {
+        private static float DistToPt(float3 p, float4 plane)
+        {
+            return p.x * plane.x + p.y * plane.y + p.z * plane.z + plane.w;
+        }
+
+        private static PlaneTriResult getSidePlane(float3 p, float4 plane, float epsilon)
+        {
+            float d = DistToPt(p, plane);
+
+            if ((d + epsilon) > 0f)
+                return PlaneTriResult.PTR_FRONT; // it is 'in front' within the provided epsilon value.
+
+            return PlaneTriResult.PTR_BACK;
+        }
+
+        private static void add(float3 p, float3[] dest, ref int pcount)
+        {
+            dest[pcount++] = new float3(p);
+            Debug.Assert(pcount <= 4);
+        }
+
+        // assumes that the points are on opposite sides of the plane!
+        private static void intersect(float3 p1, float3 p2, float3 split, float4 plane)
+        {
+            float dp1 = DistToPt(p1, plane);
+            float[] dir = new float[3];
+
+            dir[0] = p2[0] - p1[0];
+            dir[1] = p2[1] - p1[1];
+            dir[2] = p2[2] - p1[2];
+
+            float dot1 = dir[0] * plane[0] + dir[1] * plane[1] + dir[2] * plane[2];
+            float dot2 = dp1 - plane[3];
+
+            float t = -(plane[3] + dot2) / dot1;
+
+            split.x = (dir[0] * t) + p1[0];
+            split.y = (dir[1] * t) + p1[1];
+            split.z = (dir[2] * t) + p1[2];
+        }
+
+        public static PlaneTriResult planeTriIntersection(float4 plane, FaceTri triangle, float epsilon, ref float3[] front, out int fcount, ref float3[] back, out int bcount)
+        {
+            fcount = 0;
+            bcount = 0;
+
+            // get the three vertices of the triangle.
+            float3 p1 = triangle.P1;
+            float3 p2 = triangle.P2;
+            float3 p3 = triangle.P3;
+
+            PlaneTriResult r1 = getSidePlane(p1, plane, epsilon); // compute the side of the plane each vertex is on
+            PlaneTriResult r2 = getSidePlane(p2, plane, epsilon);
+            PlaneTriResult r3 = getSidePlane(p3, plane, epsilon);
+
+            if (r1 == r2 && r1 == r3) // if all three vertices are on the same side of the plane.
+            {
+                if (r1 == PlaneTriResult.PTR_FRONT) // if all three are in front of the plane, then copy to the 'front' output triangle.
+                {
+                    add(p1, front, ref fcount);
+                    add(p2, front, ref fcount);
+                    add(p3, front, ref fcount);
+                }
+                else
+                {
+                    add(p1, back, ref bcount); // if all three are in 'back' then copy to the 'back' output triangle.
+                    add(p2, back, ref bcount);
+                    add(p3, back, ref bcount);
+                }
+                return r1; // if all three points are on the same side of the plane return result
+            }
+
+            // ok.. we need to split the triangle at the plane.
+
+            // First test ray segment P1 to P2
+            if (r1 == r2) // if these are both on the same side...
+            {
+                if (r1 == PlaneTriResult.PTR_FRONT)
+                {
+                    add(p1, front, ref fcount);
+                    add(p2, front, ref fcount);
+                }
+                else
+                {
+                    add(p1, back, ref bcount);
+                    add(p2, back, ref bcount);
+                }
+            }
+            else
+            {
+                float3 split = new float3();
+                intersect(p1, p2, split, plane);
+
+                if (r1 == PlaneTriResult.PTR_FRONT)
+                {
+
+                    add(p1, front, ref fcount);
+                    add(split, front, ref fcount);
+
+                    add(split, back, ref bcount);
+                    add(p2, back, ref bcount);
+
+                }
+                else
+                {
+                    add(p1, back, ref bcount);
+                    add(split, back, ref bcount);
+
+                    add(split, front, ref fcount);
+                    add(p2, front, ref fcount);
+                }
+
+            }
+
+            // Next test ray segment P2 to P3
+            if (r2 == r3) // if these are both on the same side...
+            {
+                if (r3 == PlaneTriResult.PTR_FRONT)
+                {
+                    add(p3, front, ref fcount);
+                }
+                else
+                {
+                    add(p3, back, ref bcount);
+                }
+            }
+            else
+            {
+                float3 split = new float3(); // split the point
+                intersect(p2, p3, split, plane);
+
+                if (r3 == PlaneTriResult.PTR_FRONT)
+                {
+                    add(split, front, ref fcount);
+                    add(split, back, ref bcount);
+
+                    add(p3, front, ref fcount);
+                }
+                else
+                {
+                    add(split, front, ref fcount);
+                    add(split, back, ref bcount);
+
+                    add(p3, back, ref bcount);
+                }
+            }
+
+            // Next test ray segment P3 to P1
+            if (r3 != r1) // if these are both on the same side...
+            {
+                float3 split = new float3(); // split the point
+                intersect(p3, p1, split, plane);
+
+                if (r1 == PlaneTriResult.PTR_FRONT)
+                {
+                    add(split, front, ref fcount);
+                    add(split, back, ref bcount);
+                }
+                else
+                {
+                    add(split, front, ref fcount);
+                    add(split, back, ref bcount);
+                }
+            }
+
+            return PlaneTriResult.PTR_SPLIT;
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/Properties/AssemblyInfo.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/Properties/AssemblyInfo.cs
new file mode 100644
index 0000000..4285e8c
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/Properties/AssemblyInfo.cs
@@ -0,0 +1,36 @@
+using System.Reflection;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+
+// General Information about an assembly is controlled through the following 
+// set of attributes. Change these attribute values to modify the information
+// associated with an assembly.
+[assembly: AssemblyTitle("ConvexDecompositionDotNet")]
+[assembly: AssemblyDescription("")]
+[assembly: AssemblyConfiguration("")]
+[assembly: AssemblyCompany("Intel Corporation")]
+[assembly: AssemblyProduct("ConvexDecompositionDotNet")]
+[assembly: AssemblyCopyright("Copyright © Intel Corporation 2010")]
+[assembly: AssemblyTrademark("")]
+[assembly: AssemblyCulture("")]
+
+// Setting ComVisible to false makes the types in this assembly not visible 
+// to COM components.  If you need to access a type in this assembly from 
+// COM, set the ComVisible attribute to true on that type.
+[assembly: ComVisible(false)]
+
+// The following GUID is for the ID of the typelib if this project is exposed to COM
+[assembly: Guid("2a1c9467-1a17-4c8d-bf9f-4b4d86dd0cbb")]
+
+// Version information for an assembly consists of the following four values:
+//
+//      Major Version
+//      Minor Version 
+//      Build Number
+//      Revision
+//
+// You can specify all the values or you can default the Build and Revision Numbers 
+// by using the '*' as shown below:
+// [assembly: AssemblyVersion("1.0.*")]
+[assembly: AssemblyVersion("1.0.0.0")]
+[assembly: AssemblyFileVersion("1.0.0.0")]
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/Quaternion.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/Quaternion.cs
new file mode 100644
index 0000000..0ba8f17
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/Quaternion.cs
@@ -0,0 +1,209 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class Quaternion : float4
+    {
+        public Quaternion()
+        {
+            x = y = z = 0.0f;
+            w = 1.0f;
+        }
+
+        public Quaternion(float3 v, float t)
+        {
+            v = float3.normalize(v);
+            w = (float)Math.Cos(t / 2.0f);
+            v = v * (float)Math.Sin(t / 2.0f);
+            x = v.x;
+            y = v.y;
+            z = v.z;
+        }
+
+        public Quaternion(float _x, float _y, float _z, float _w)
+        {
+            x = _x;
+            y = _y;
+            z = _z;
+            w = _w;
+        }
+
+        public float angle()
+        {
+            return (float)Math.Acos(w) * 2.0f;
+        }
+
+        public float3 axis()
+        {
+            float3 a = new float3(x, y, z);
+            if (Math.Abs(angle()) < 0.0000001f)
+                return new float3(1f, 0f, 0f);
+            return a * (1 / (float)Math.Sin(angle() / 2.0f));
+        }
+
+        public float3 xdir()
+        {
+            return new float3(1 - 2 * (y * y + z * z), 2 * (x * y + w * z), 2 * (x * z - w * y));
+        }
+
+        public float3 ydir()
+        {
+            return new float3(2 * (x * y - w * z), 1 - 2 * (x * x + z * z), 2 * (y * z + w * x));
+        }
+
+        public float3 zdir()
+        {
+            return new float3(2 * (x * z + w * y), 2 * (y * z - w * x), 1 - 2 * (x * x + y * y));
+        }
+
+        public float3x3 getmatrix()
+        {
+            return new float3x3(xdir(), ydir(), zdir());
+        }
+
+        public static implicit operator float3x3(Quaternion q)
+        {
+            return q.getmatrix();
+        }
+
+        public static Quaternion operator *(Quaternion a, Quaternion b)
+        {
+            Quaternion c = new Quaternion();
+            c.w = a.w * b.w - a.x * b.x - a.y * b.y - a.z * b.z;
+            c.x = a.w * b.x + a.x * b.w + a.y * b.z - a.z * b.y;
+            c.y = a.w * b.y - a.x * b.z + a.y * b.w + a.z * b.x;
+            c.z = a.w * b.z + a.x * b.y - a.y * b.x + a.z * b.w;
+            return c;
+        }
+
+        public static float3 operator *(Quaternion q, float3 v)
+        {
+            // The following is equivalent to:
+            //return (q.getmatrix() * v);
+            float qx2 = q.x * q.x;
+            float qy2 = q.y * q.y;
+            float qz2 = q.z * q.z;
+
+            float qxqy = q.x * q.y;
+            float qxqz = q.x * q.z;
+            float qxqw = q.x * q.w;
+            float qyqz = q.y * q.z;
+            float qyqw = q.y * q.w;
+            float qzqw = q.z * q.w;
+            return new float3((1 - 2 * (qy2 + qz2)) * v.x + (2 * (qxqy - qzqw)) * v.y + (2 * (qxqz + qyqw)) * v.z, (2 * (qxqy + qzqw)) * v.x + (1 - 2 * (qx2 + qz2)) * v.y + (2 * (qyqz - qxqw)) * v.z, (2 * (qxqz - qyqw)) * v.x + (2 * (qyqz + qxqw)) * v.y + (1 - 2 * (qx2 + qy2)) * v.z);
+        }
+
+        public static Quaternion operator +(Quaternion a, Quaternion b)
+        {
+            return new Quaternion(a.x + b.x, a.y + b.y, a.z + b.z, a.w + b.w);
+        }
+
+        public static Quaternion operator *(Quaternion a, float b)
+            {
+                    return new Quaternion(a.x *b, a.y *b, a.z *b, a.w *b);
+            }
+
+        public static Quaternion normalize(Quaternion a)
+        {
+            float m = (float)Math.Sqrt(a.w * a.w + a.x * a.x + a.y * a.y + a.z * a.z);
+            if (m < 0.000000001f)
+            {
+                a.w = 1;
+                a.x = a.y = a.z = 0;
+                return a;
+            }
+            return a * (1f / m);
+        }
+
+        public static float dot(Quaternion a, Quaternion b)
+        {
+            return (a.w * b.w + a.x * b.x + a.y * b.y + a.z * b.z);
+        }
+
+        public static Quaternion slerp(Quaternion a, Quaternion b, float interp)
+        {
+            if (dot(a, b) < 0.0)
+            {
+                a.w = -a.w;
+                a.x = -a.x;
+                a.y = -a.y;
+                a.z = -a.z;
+            }
+            float d = dot(a, b);
+            if (d >= 1.0)
+            {
+                return a;
+            }
+            float theta = (float)Math.Acos(d);
+            if (theta == 0.0f)
+            {
+                return (a);
+            }
+            return a * ((float)Math.Sin(theta - interp * theta) / (float)Math.Sin(theta)) + b * ((float)Math.Sin(interp * theta) / (float)Math.Sin(theta));
+        }
+
+        public static Quaternion Interpolate(Quaternion q0, Quaternion q1, float alpha)
+        {
+            return slerp(q0, q1, alpha);
+        }
+
+        public static Quaternion Inverse(Quaternion q)
+        {
+            return new Quaternion(-q.x, -q.y, -q.z, q.w);
+        }
+
+        public static Quaternion YawPitchRoll(float yaw, float pitch, float roll)
+        {
+            roll *= (3.14159264f / 180.0f);
+            yaw *= (3.14159264f / 180.0f);
+            pitch *= (3.14159264f / 180.0f);
+            return new Quaternion(new float3(0.0f, 0.0f, 1.0f), yaw) * new Quaternion(new float3(1.0f, 0.0f, 0.0f), pitch) * new Quaternion(new float3(0.0f, 1.0f, 0.0f), roll);
+        }
+
+        public static float Yaw(Quaternion q)
+        {
+            float3 v = q.ydir();
+            return (v.y == 0.0 && v.x == 0.0) ? 0.0f : (float)Math.Atan2(-v.x, v.y) * (180.0f / 3.14159264f);
+        }
+
+        public static float Pitch(Quaternion q)
+        {
+            float3 v = q.ydir();
+            return (float)Math.Atan2(v.z, Math.Sqrt(v.x * v.x + v.y * v.y)) * (180.0f / 3.14159264f);
+        }
+
+        public static float Roll(Quaternion q)
+        {
+            q = new Quaternion(new float3(0.0f, 0.0f, 1.0f), -Yaw(q) * (3.14159264f / 180.0f)) * q;
+            q = new Quaternion(new float3(1.0f, 0.0f, 0.0f), -Pitch(q) * (3.14159264f / 180.0f)) * q;
+            return (float)Math.Atan2(-q.xdir().z, q.xdir().x) * (180.0f / 3.14159264f);
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/README.txt b/OpenSim/Region/Physics/ConvexDecompositionDotNet/README.txt
new file mode 100644
index 0000000..fc53ae7
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/README.txt
@@ -0,0 +1,7 @@
+ConvexDecompositionDotNet
+=========================
+
+A C# port of the ConvexDecomposition library by John W. Ratcliff and Stan Melax. 
+The original C++ version is available at <http://codesuppository.googlecode.com/>. 
+See the blog post at <http://codesuppository.blogspot.com/2006/08/approximate-convexdecomposition.html> 
+for a thorough explanation of generating convex hulls from concave meshes.
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/SplitPlane.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/SplitPlane.cs
new file mode 100644
index 0000000..9f06a9a
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/SplitPlane.cs
@@ -0,0 +1,265 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class Rect3d
+    {
+        public float[] mMin = new float[3];
+        public float[] mMax = new float[3];
+
+        public Rect3d()
+        {
+        }
+
+        public Rect3d(float[] bmin, float[] bmax)
+        {
+            mMin[0] = bmin[0];
+            mMin[1] = bmin[1];
+            mMin[2] = bmin[2];
+
+            mMax[0] = bmax[0];
+            mMax[1] = bmax[1];
+            mMax[2] = bmax[2];
+        }
+
+        public void SetMin(float[] bmin)
+        {
+            mMin[0] = bmin[0];
+            mMin[1] = bmin[1];
+            mMin[2] = bmin[2];
+        }
+
+        public void SetMax(float[] bmax)
+        {
+            mMax[0] = bmax[0];
+            mMax[1] = bmax[1];
+            mMax[2] = bmax[2];
+        }
+
+        public void SetMin(float x, float y, float z)
+        {
+            mMin[0] = x;
+            mMin[1] = y;
+            mMin[2] = z;
+        }
+
+        public void SetMax(float x, float y, float z)
+        {
+            mMax[0] = x;
+            mMax[1] = y;
+            mMax[2] = z;
+        }
+    }
+
+    public static class SplitPlane
+    {
+        public static bool computeSplitPlane(List<float3> vertices, List<int> indices, ref float4 plane)
+        {
+            float[] bmin = { Single.MaxValue, Single.MaxValue, Single.MaxValue };
+            float[] bmax = { Single.MinValue, Single.MinValue, Single.MinValue };
+
+            for (int i = 0; i < vertices.Count; i++)
+            {
+                float3 p = vertices[i];
+
+                if (p[0] < bmin[0])
+                    bmin[0] = p[0];
+                if (p[1] < bmin[1])
+                    bmin[1] = p[1];
+                if (p[2] < bmin[2])
+                    bmin[2] = p[2];
+
+                if (p[0] > bmax[0])
+                    bmax[0] = p[0];
+                if (p[1] > bmax[1])
+                    bmax[1] = p[1];
+                if (p[2] > bmax[2])
+                    bmax[2] = p[2];
+            }
+
+            float dx = bmax[0] - bmin[0];
+            float dy = bmax[1] - bmin[1];
+            float dz = bmax[2] - bmin[2];
+
+            float laxis = dx;
+
+            int axis = 0;
+
+            if (dy > dx)
+            {
+                axis = 1;
+                laxis = dy;
+            }
+
+            if (dz > dx && dz > dy)
+            {
+                axis = 2;
+                laxis = dz;
+            }
+
+            float[] p1 = new float[3];
+            float[] p2 = new float[3];
+            float[] p3 = new float[3];
+
+            p3[0] = p2[0] = p1[0] = bmin[0] + dx * 0.5f;
+            p3[1] = p2[1] = p1[1] = bmin[1] + dy * 0.5f;
+            p3[2] = p2[2] = p1[2] = bmin[2] + dz * 0.5f;
+
+            Rect3d b = new Rect3d(bmin, bmax);
+
+            Rect3d b1 = new Rect3d();
+            Rect3d b2 = new Rect3d();
+
+            splitRect(axis, b, b1, b2, p1);
+
+            switch (axis)
+            {
+                case 0:
+                    p2[1] = bmin[1];
+                    p2[2] = bmin[2];
+
+                    if (dz > dy)
+                    {
+                        p3[1] = bmax[1];
+                        p3[2] = bmin[2];
+                    }
+                    else
+                    {
+                        p3[1] = bmin[1];
+                        p3[2] = bmax[2];
+                    }
+
+                    break;
+                case 1:
+                    p2[0] = bmin[0];
+                    p2[2] = bmin[2];
+
+                    if (dx > dz)
+                    {
+                        p3[0] = bmax[0];
+                        p3[2] = bmin[2];
+                    }
+                    else
+                    {
+                        p3[0] = bmin[0];
+                        p3[2] = bmax[2];
+                    }
+
+                    break;
+                case 2:
+                    p2[0] = bmin[0];
+                    p2[1] = bmin[1];
+
+                    if (dx > dy)
+                    {
+                        p3[0] = bmax[0];
+                        p3[1] = bmin[1];
+                    }
+                    else
+                    {
+                        p3[0] = bmin[0];
+                        p3[1] = bmax[1];
+                    }
+
+                    break;
+            }
+
+            computePlane(p1, p2, p3, plane);
+
+            return true;
+        }
+
+        internal static void computePlane(float[] A, float[] B, float[] C, float4 plane)
+        {
+            float vx = (B[0] - C[0]);
+            float vy = (B[1] - C[1]);
+            float vz = (B[2] - C[2]);
+
+            float wx = (A[0] - B[0]);
+            float wy = (A[1] - B[1]);
+            float wz = (A[2] - B[2]);
+
+            float vw_x = vy * wz - vz * wy;
+            float vw_y = vz * wx - vx * wz;
+            float vw_z = vx * wy - vy * wx;
+
+            float mag = (float)Math.Sqrt((vw_x * vw_x) + (vw_y * vw_y) + (vw_z * vw_z));
+
+            if (mag < 0.000001f)
+            {
+                mag = 0;
+            }
+            else
+            {
+                mag = 1.0f / mag;
+            }
+
+            float x = vw_x * mag;
+            float y = vw_y * mag;
+            float z = vw_z * mag;
+
+            float D = 0.0f - ((x * A[0]) + (y * A[1]) + (z * A[2]));
+
+            plane.x = x;
+            plane.y = y;
+            plane.z = z;
+            plane.w = D;
+        }
+
+        public static void splitRect(int axis, Rect3d source, Rect3d b1, Rect3d b2, float[] midpoint)
+        {
+            switch (axis)
+            {
+                case 0:
+                    b1.SetMin(source.mMin);
+                    b1.SetMax(midpoint[0], source.mMax[1], source.mMax[2]);
+
+                    b2.SetMin(midpoint[0], source.mMin[1], source.mMin[2]);
+                    b2.SetMax(source.mMax);
+                    break;
+                case 1:
+                    b1.SetMin(source.mMin);
+                    b1.SetMax(source.mMax[0], midpoint[1], source.mMax[2]);
+
+                    b2.SetMin(source.mMin[0], midpoint[1], source.mMin[2]);
+                    b2.SetMax(source.mMax);
+                    break;
+                case 2:
+                    b1.SetMin(source.mMin);
+                    b1.SetMax(source.mMax[0], source.mMax[1], midpoint[2]);
+
+                    b2.SetMin(source.mMin[0], source.mMin[1], midpoint[2]);
+                    b2.SetMax(source.mMax);
+                    break;
+            }
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/VertexLookup.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/VertexLookup.cs
new file mode 100644
index 0000000..6f17c9f
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/VertexLookup.cs
@@ -0,0 +1,70 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class VertexPool
+    {
+        private List<float3> mVertices = new List<float3>();
+        private Dictionary<float3, int> mIndices = new Dictionary<float3, int>();
+
+        public int getIndex(float3 vtx)
+        {
+            int idx;
+            if (mIndices.TryGetValue(vtx, out idx))
+                return idx;
+
+            idx = mVertices.Count;
+            mVertices.Add(vtx);
+            mIndices.Add(vtx, idx);
+            return idx;
+        }
+
+        public float3 Get(int idx)
+        {
+            return mVertices[idx];
+        }
+
+        public int GetSize()
+        {
+            return mVertices.Count;
+        }
+
+        public List<float3> GetVertices()
+        {
+            return mVertices;
+        }
+
+        public void Clear()
+        {
+            mVertices.Clear();
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/float2.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/float2.cs
new file mode 100644
index 0000000..ce88fc8
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/float2.cs
@@ -0,0 +1,70 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class float2
+    {
+        public float x;
+        public float y;
+
+        public float2()
+        {
+        }
+
+        public float2(float _x, float _y)
+        {
+            x = _x;
+            y = _y;
+        }
+
+        public float this[int i]
+        {
+            get
+            {
+                switch (i)
+                {
+                    case 0: return x;
+                    case 1: return y;
+                }
+                throw new ArgumentOutOfRangeException();
+            }
+        }
+
+        public static float2 operator -(float2 a, float2 b)
+        {
+            return new float2(a.x - b.x, a.y - b.y);
+        }
+
+        public static float2 operator +(float2 a, float2 b)
+        {
+            return new float2(a.x + b.x, a.y + b.y);
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/float3.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/float3.cs
new file mode 100644
index 0000000..4389114
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/float3.cs
@@ -0,0 +1,444 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class float3 : IEquatable<float3>
+    {
+        public float x;
+        public float y;
+        public float z;
+
+        public float3()
+        {
+            x = 0;
+            y = 0;
+            z = 0;
+        }
+
+        public float3(float _x, float _y, float _z)
+        {
+            x = _x;
+            y = _y;
+            z = _z;
+        }
+
+        public float3(float3 f)
+        {
+            x = f.x;
+            y = f.y;
+            z = f.z;
+        }
+
+        public float this[int i]
+        {
+            get
+            {
+                switch (i)
+                {
+                    case 0: return x;
+                    case 1: return y;
+                    case 2: return z;
+                }
+                throw new ArgumentOutOfRangeException();
+            }
+        }
+
+        public float Distance(float3 a)
+        {
+            float3 d = new float3(a.x - x, a.y - y, a.z - z);
+            return d.Length();
+        }
+
+        public float Distance2(float3 a)
+        {
+            float dx = a.x - x;
+            float dy = a.y - y;
+            float dz = a.z - z;
+            return dx * dx + dy * dy + dz * dz;
+        }
+
+        public float Length()
+        {
+            return (float)Math.Sqrt(x * x + y * y + z * z);
+        }
+
+        public float Area(float3 p1, float3 p2)
+        {
+            float A = Partial(p1);
+            A += p1.Partial(p2);
+            A += p2.Partial(this);
+            return A * 0.5f;
+        }
+
+        public float Partial(float3 p)
+        {
+            return (x * p.y) - (p.x * y);
+        }
+
+        // Given a point and a line (defined by two points), compute the closest point
+        // in the line.  (The line is treated as infinitely long.)
+        public void NearestPointInLine(float3 point, float3 line0, float3 line1)
+        {
+            float3 nearestPoint = new float3();
+            float3 lineDelta = line1 - line0;
+
+            // Handle degenerate lines
+            if (lineDelta == float3.Zero)
+            {
+                nearestPoint = line0;
+            }
+            else
+            {
+                float delta = float3.dot(point - line0, lineDelta) / float3.dot(lineDelta, lineDelta);
+                nearestPoint = line0 + lineDelta * delta;
+            }
+
+            this.x = nearestPoint.x;
+            this.y = nearestPoint.y;
+            this.z = nearestPoint.z;
+        }
+
+        // Given a point and a line segment (defined by two points), compute the closest point
+        // in the line.  Cap the point at the endpoints of the line segment.
+        public void NearestPointInLineSegment(float3 point, float3 line0, float3 line1)
+        {
+            float3 nearestPoint = new float3();
+            float3 lineDelta = line1 - line0;
+
+            // Handle degenerate lines
+            if (lineDelta == Zero)
+            {
+                nearestPoint = line0;
+            }
+            else
+            {
+                float delta = float3.dot(point - line0, lineDelta) / float3.dot(lineDelta, lineDelta);
+
+                // Clamp the point to conform to the segment's endpoints
+                if (delta < 0)
+                    delta = 0;
+                else if (delta > 1)
+                    delta = 1;
+
+                nearestPoint = line0 + lineDelta * delta;
+            }
+
+            this.x = nearestPoint.x;
+            this.y = nearestPoint.y;
+            this.z = nearestPoint.z;
+        }
+
+        // Given a point and a triangle (defined by three points), compute the closest point
+        // in the triangle.  Clamp the point so it's confined to the area of the triangle.
+        public void NearestPointInTriangle(float3 point, float3 triangle0, float3 triangle1, float3 triangle2)
+        {
+            float3 nearestPoint = new float3();
+
+            float3 lineDelta0 = triangle1 - triangle0;
+            float3 lineDelta1 = triangle2 - triangle0;
+
+            // Handle degenerate triangles
+            if ((lineDelta0 == Zero) || (lineDelta1 == Zero))
+            {
+                nearestPoint.NearestPointInLineSegment(point, triangle1, triangle2);
+            }
+            else if (lineDelta0 == lineDelta1)
+            {
+                nearestPoint.NearestPointInLineSegment(point, triangle0, triangle1);
+            }
+            else
+            {
+                float3[] axis = new float3[3] { new float3(), new float3(), new float3() };
+                axis[0].NearestPointInLine(triangle0, triangle1, triangle2);
+                axis[1].NearestPointInLine(triangle1, triangle0, triangle2);
+                axis[2].NearestPointInLine(triangle2, triangle0, triangle1);
+
+                float3 axisDot = new float3();
+                axisDot.x = dot(triangle0 - axis[0], point - axis[0]);
+                axisDot.y = dot(triangle1 - axis[1], point - axis[1]);
+                axisDot.z = dot(triangle2 - axis[2], point - axis[2]);
+
+                bool bForce = true;
+                float bestMagnitude2 = 0;
+                float closeMagnitude2;
+                float3 closePoint = new float3();
+
+                if (axisDot.x < 0f)
+                {
+                    closePoint.NearestPointInLineSegment(point, triangle1, triangle2);
+                    closeMagnitude2 = point.Distance2(closePoint);
+                    if (bForce || (bestMagnitude2 > closeMagnitude2))
+                    {
+                        bForce = false;
+                        bestMagnitude2 = closeMagnitude2;
+                        nearestPoint = closePoint;
+                    }
+                }
+                if (axisDot.y < 0f)
+                {
+                    closePoint.NearestPointInLineSegment(point, triangle0, triangle2);
+                    closeMagnitude2 = point.Distance2(closePoint);
+                    if (bForce || (bestMagnitude2 > closeMagnitude2))
+                    {
+                        bForce = false;
+                        bestMagnitude2 = closeMagnitude2;
+                        nearestPoint = closePoint;
+                    }
+                }
+                if (axisDot.z < 0f)
+                {
+                    closePoint.NearestPointInLineSegment(point, triangle0, triangle1);
+                    closeMagnitude2 = point.Distance2(closePoint);
+                    if (bForce || (bestMagnitude2 > closeMagnitude2))
+                    {
+                        bForce = false;
+                        bestMagnitude2 = closeMagnitude2;
+                        nearestPoint = closePoint;
+                    }
+                }
+
+                // If bForce is true at this point, it means the nearest point lies
+                // inside the triangle; use the nearest-point-on-a-plane equation
+                if (bForce)
+                {
+                    float3 normal;
+
+                    // Get the normal of the polygon (doesn't have to be a unit vector)
+                    normal = float3.cross(lineDelta0, lineDelta1);
+
+                    float3 pointDelta = point - triangle0;
+                    float delta = float3.dot(normal, pointDelta) / float3.dot(normal, normal);
+
+                    nearestPoint = point - normal * delta;
+                }
+            }
+
+            this.x = nearestPoint.x;
+            this.y = nearestPoint.y;
+            this.z = nearestPoint.z;
+        }
+
+        public static float3 operator +(float3 a, float3 b)
+        {
+            return new float3(a.x + b.x, a.y + b.y, a.z + b.z);
+        }
+
+        public static float3 operator -(float3 a, float3 b)
+        {
+            return new float3(a.x - b.x, a.y - b.y, a.z - b.z);
+        }
+
+        public static float3 operator -(float3 a, float s)
+        {
+            return new float3(a.x - s, a.y - s, a.z - s);
+        }
+
+        public static float3 operator -(float3 v)
+        {
+            return new float3(-v.x, -v.y, -v.z);
+        }
+
+        public static float3 operator *(float3 v, float s)
+        {
+            return new float3(v.x * s, v.y * s, v.z * s);
+        }
+
+        public static float3 operator *(float s, float3 v)
+        {
+            return new float3(v.x * s, v.y * s, v.z * s);
+        }
+
+        public static float3 operator *(float3 v, float3x3 m)
+        {
+            return new float3((m.x.x * v.x + m.y.x * v.y + m.z.x * v.z), (m.x.y * v.x + m.y.y * v.y + m.z.y * v.z), (m.x.z * v.x + m.y.z * v.y + m.z.z * v.z));
+        }
+
+        public static float3 operator *(float3x3 m, float3 v)
+        {
+            return new float3(dot(m.x, v), dot(m.y, v), dot(m.z, v));
+        }
+
+        public static float3 operator /(float3 v, float s)
+        {
+            float sinv = 1.0f / s;
+            return new float3(v.x * sinv, v.y * sinv, v.z * sinv);
+        }
+
+        public bool Equals(float3 other)
+        {
+            return this == other;
+        }
+
+        public override bool Equals(object obj)
+        {
+            float3 f = obj as float3;
+            if (f == null)
+                return false;
+
+            return this == f;
+        }
+
+        public override int GetHashCode()
+        {
+            return x.GetHashCode() ^ y.GetHashCode() ^ z.GetHashCode();
+        }
+
+        public static bool operator ==(float3 a, float3 b)
+        {
+            // If both are null, or both are same instance, return true.
+            if (System.Object.ReferenceEquals(a, b))
+                return true;
+            // If one is null, but not both, return false.
+            if (((object)a == null) || ((object)b == null))
+                return false;
+
+            return (a.x == b.x && a.y == b.y && a.z == b.z);
+        }
+
+        public static bool operator !=(float3 a, float3 b)
+        {
+            return (a.x != b.x || a.y != b.y || a.z != b.z);
+        }
+
+        public static float dot(float3 a, float3 b)
+        {
+            return a.x * b.x + a.y * b.y + a.z * b.z;
+        }
+
+        public static float3 cmul(float3 v1, float3 v2)
+        {
+            return new float3(v1.x * v2.x, v1.y * v2.y, v1.z * v2.z);
+        }
+
+        public static float3 cross(float3 a, float3 b)
+        {
+            return new float3(a.y * b.z - a.z * b.y, a.z * b.x - a.x * b.z, a.x * b.y - a.y * b.x);
+        }
+
+        public static float3 Interpolate(float3 v0, float3 v1, float alpha)
+        {
+            return v0 * (1 - alpha) + v1 * alpha;
+        }
+
+        public static float3 Round(float3 a, int digits)
+        {
+            return new float3((float)Math.Round(a.x, digits), (float)Math.Round(a.y, digits), (float)Math.Round(a.z, digits));
+        }
+
+        public static float3 VectorMax(float3 a, float3 b)
+        {
+            return new float3(Math.Max(a.x, b.x), Math.Max(a.y, b.y), Math.Max(a.z, b.z));
+        }
+
+        public static float3 VectorMin(float3 a, float3 b)
+        {
+            return new float3(Math.Min(a.x, b.x), Math.Min(a.y, b.y), Math.Min(a.z, b.z));
+        }
+
+        public static float3 vabs(float3 v)
+        {
+            return new float3(Math.Abs(v.x), Math.Abs(v.y), Math.Abs(v.z));
+        }
+
+        public static float magnitude(float3 v)
+        {
+            return (float)Math.Sqrt(v.x * v.x + v.y * v.y + v.z * v.z);
+        }
+
+        public static float3 normalize(float3 v)
+        {
+            float d = magnitude(v);
+            if (d == 0)
+                d = 0.1f;
+            d = 1 / d;
+            return new float3(v.x * d, v.y * d, v.z * d);
+        }
+
+        public static float3 safenormalize(float3 v)
+        {
+            if (magnitude(v) <= 0.0f)
+                return new float3(1, 0, 0);
+            else
+                return normalize(v);
+        }
+
+        public static float Yaw(float3 v)
+        {
+            return (v.y == 0.0 && v.x == 0.0) ? 0.0f : (float)Math.Atan2(-v.x, v.y) * (180.0f / 3.14159264f);
+        }
+
+        public static float Pitch(float3 v)
+        {
+            return (float)Math.Atan2(v.z, Math.Sqrt(v.x * v.x + v.y * v.y)) * (180.0f / 3.14159264f);
+        }
+
+        public float ComputePlane(float3 A, float3 B, float3 C)
+        {
+            float vx, vy, vz, wx, wy, wz, vw_x, vw_y, vw_z, mag;
+
+            vx = (B.x - C.x);
+            vy = (B.y - C.y);
+            vz = (B.z - C.z);
+
+            wx = (A.x - B.x);
+            wy = (A.y - B.y);
+            wz = (A.z - B.z);
+
+            vw_x = vy * wz - vz * wy;
+            vw_y = vz * wx - vx * wz;
+            vw_z = vx * wy - vy * wx;
+
+            mag = (float)Math.Sqrt((vw_x * vw_x) + (vw_y * vw_y) + (vw_z * vw_z));
+
+            if (mag < 0.000001f)
+            {
+                mag = 0;
+            }
+            else
+            {
+                mag = 1.0f / mag;
+            }
+
+            x = vw_x * mag;
+            y = vw_y * mag;
+            z = vw_z * mag;
+
+            float D = 0.0f - ((x * A.x) + (y * A.y) + (z * A.z));
+            return D;
+        }
+
+        public override string ToString()
+        {
+            return String.Format("<{0}, {1}, {2}>", x, y, z);
+        }
+
+        public static readonly float3 Zero = new float3();
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/float3x3.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/float3x3.cs
new file mode 100644
index 0000000..76cf063
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/float3x3.cs
@@ -0,0 +1,195 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class float3x3
+    {
+        public float3 x = new float3();
+        public float3 y = new float3();
+        public float3 z = new float3();
+
+        public float3x3()
+        {
+        }
+
+        public float3x3(float xx, float xy, float xz, float yx, float yy, float yz, float zx, float zy, float zz)
+        {
+            x = new float3(xx, xy, xz);
+            y = new float3(yx, yy, yz);
+            z = new float3(zx, zy, zz);
+        }
+
+        public float3x3(float3 _x, float3 _y, float3 _z)
+        {
+            x = new float3(_x);
+            y = new float3(_y);
+            z = new float3(_z);
+        }
+
+        public float3 this[int i]
+        {
+            get
+            {
+                switch (i)
+                {
+                    case 0: return x;
+                    case 1: return y;
+                    case 2: return z;
+                }
+                throw new ArgumentOutOfRangeException();
+            }
+        }
+
+        public float this[int i, int j]
+        {
+            get
+            {
+                switch (i)
+                {
+                    case 0:
+                        switch (j)
+                        {
+                            case 0: return x.x;
+                            case 1: return x.y;
+                            case 2: return x.z;
+                        }
+                        break;
+                    case 1:
+                        switch (j)
+                        {
+                            case 0: return y.x;
+                            case 1: return y.y;
+                            case 2: return y.z;
+                        }
+                        break;
+                    case 2:
+                        switch (j)
+                        {
+                            case 0: return z.x;
+                            case 1: return z.y;
+                            case 2: return z.z;
+                        }
+                        break;
+                }
+                throw new ArgumentOutOfRangeException();
+            }
+            set
+            {
+                switch (i)
+                {
+                    case 0:
+                        switch (j)
+                        {
+                            case 0: x.x = value; return;
+                            case 1: x.y = value; return;
+                            case 2: x.z = value; return;
+                        }
+                        break;
+                    case 1:
+                        switch (j)
+                        {
+                            case 0: y.x = value; return;
+                            case 1: y.y = value; return;
+                            case 2: y.z = value; return;
+                        }
+                        break;
+                    case 2:
+                        switch (j)
+                        {
+                            case 0: z.x = value; return;
+                            case 1: z.y = value; return;
+                            case 2: z.z = value; return;
+                        }
+                        break;
+                }
+                throw new ArgumentOutOfRangeException();
+            }
+        }
+
+        public static float3x3 Transpose(float3x3 m)
+        {
+            return new float3x3(new float3(m.x.x, m.y.x, m.z.x), new float3(m.x.y, m.y.y, m.z.y), new float3(m.x.z, m.y.z, m.z.z));
+        }
+
+        public static float3x3 operator *(float3x3 a, float3x3 b)
+        {
+            return new float3x3(a.x * b, a.y * b, a.z * b);
+        }
+
+        public static float3x3 operator *(float3x3 a, float s)
+        {
+            return new float3x3(a.x * s, a.y * s, a.z * s);
+        }
+
+        public static float3x3 operator /(float3x3 a, float s)
+        {
+            float t = 1f / s;
+            return new float3x3(a.x * t, a.y * t, a.z * t);
+        }
+
+        public static float3x3 operator +(float3x3 a, float3x3 b)
+        {
+            return new float3x3(a.x + b.x, a.y + b.y, a.z + b.z);
+        }
+
+        public static float3x3 operator -(float3x3 a, float3x3 b)
+        {
+            return new float3x3(a.x - b.x, a.y - b.y, a.z - b.z);
+        }
+
+        public static float Determinant(float3x3 m)
+        {
+            return m.x.x * m.y.y * m.z.z + m.y.x * m.z.y * m.x.z + m.z.x * m.x.y * m.y.z - m.x.x * m.z.y * m.y.z - m.y.x * m.x.y * m.z.z - m.z.x * m.y.y * m.x.z;
+        }
+
+        public static float3x3 Inverse(float3x3 a)
+        {
+            float3x3 b = new float3x3();
+            float d = Determinant(a);
+            Debug.Assert(d != 0);
+            for (int i = 0; i < 3; i++)
+            {
+                for (int j = 0; j < 3; j++)
+                {
+                    int i1 = (i + 1) % 3;
+                    int i2 = (i + 2) % 3;
+                    int j1 = (j + 1) % 3;
+                    int j2 = (j + 2) % 3;
+
+                    // reverse indexs i&j to take transpose
+                    b[i, j] = (a[i1][j1] * a[i2][j2] - a[i1][j2] * a[i2][j1]) / d;
+                }
+            }
+            return b;
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/float4.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/float4.cs
new file mode 100644
index 0000000..fa60876
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/float4.cs
@@ -0,0 +1,170 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class float4
+    {
+        public float x;
+        public float y;
+        public float z;
+        public float w;
+
+        public float4()
+        {
+            x = 0;
+            y = 0;
+            z = 0;
+            w = 0;
+        }
+
+        public float4(float _x, float _y, float _z, float _w)
+        {
+            x = _x;
+            y = _y;
+            z = _z;
+            w = _w;
+        }
+
+        public float4(float3 v, float _w)
+        {
+            x = v.x;
+            y = v.y;
+            z = v.z;
+            w = _w;
+        }
+
+        public float4(float4 f)
+        {
+            x = f.x;
+            y = f.y;
+            z = f.z;
+            w = f.w;
+        }
+
+        public float this[int i]
+        {
+            get
+            {
+                switch (i)
+                {
+                    case 0: return x;
+                    case 1: return y;
+                    case 2: return z;
+                    case 3: return w;
+                }
+                throw new ArgumentOutOfRangeException();
+            }
+        }
+
+        public float3 xyz()
+        {
+            return new float3(x, y, z);
+        }
+
+        public void setxyz(float3 xyz)
+        {
+            x = xyz.x;
+            y = xyz.y;
+            z = xyz.z;
+        }
+
+        public override int GetHashCode()
+        {
+            return x.GetHashCode() ^ y.GetHashCode() ^ z.GetHashCode() ^ w.GetHashCode();
+        }
+
+        public override bool Equals(object obj)
+        {
+            float4 f = obj as float4;
+            if (f == null)
+                return false;
+
+            return this == f;
+        }
+
+        public static float4 Homogenize(float3 v3)
+        {
+            return Homogenize(v3, 1.0f);
+        }
+
+        //C++ TO C# CONVERTER NOTE: C# does not allow default values for parameters. Overloaded methods are inserted above.
+        //ORIGINAL LINE: float4 Homogenize(const float3 &v3, const float &w =1.0f)
+        public static float4 Homogenize(float3 v3, float w)
+        {
+            return new float4(v3.x, v3.y, v3.z, w);
+        }
+
+        public static float4 cmul(float4 a, float4 b)
+        {
+            return new float4(a.x * b.x, a.y * b.y, a.z * b.z, a.w * b.w);
+        }
+
+        public static float4 operator +(float4 a, float4 b)
+        {
+            return new float4(a.x + b.x, a.y + b.y, a.z + b.z, a.w + b.w);
+        }
+        public static float4 operator -(float4 a, float4 b)
+        {
+            return new float4(a.x - b.x, a.y - b.y, a.z - b.z, a.w - b.w);
+        }
+
+        public static float4 operator *(float4 v, float4x4 m)
+        {
+            return v.x * m.x + v.y * m.y + v.z * m.z + v.w * m.w; // yes this actually works
+        }
+
+        public static bool operator ==(float4 a, float4 b)
+        {
+            // If both are null, or both are same instance, return true.
+            if (System.Object.ReferenceEquals(a, b))
+                return true;
+            // If one is null, but not both, return false.
+            if (((object)a == null) || ((object)b == null))
+                return false;
+
+            return (a.x == b.x && a.y == b.y && a.z == b.z && a.w == b.w);
+        }
+
+        public static bool operator !=(float4 a, float4 b)
+        {
+            return !(a == b);
+        }
+
+        public static float4 operator *(float4 v, float s)
+        {
+            return new float4(v.x * s, v.y * s, v.z * s, v.w * s);
+        }
+
+        public static float4 operator *(float s, float4 v)
+        {
+            return new float4(v.x * s, v.y * s, v.z * s, v.w * s);
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/float4x4.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/float4x4.cs
new file mode 100644
index 0000000..7d1592f
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/float4x4.cs
@@ -0,0 +1,284 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class float4x4
+    {
+        public float4 x = new float4();
+        public float4 y = new float4();
+        public float4 z = new float4();
+        public float4 w = new float4();
+
+        public float4x4()
+        {
+        }
+
+        public float4x4(float4 _x, float4 _y, float4 _z, float4 _w)
+        {
+            x = new float4(_x);
+            y = new float4(_y);
+            z = new float4(_z);
+            w = new float4(_w);
+        }
+
+        public float4x4(
+            float m00, float m01, float m02, float m03,
+            float m10, float m11, float m12, float m13,
+            float m20, float m21, float m22, float m23,
+            float m30, float m31, float m32, float m33)
+        {
+            x = new float4(m00, m01, m02, m03);
+            y = new float4(m10, m11, m12, m13);
+            z = new float4(m20, m21, m22, m23);
+            w = new float4(m30, m31, m32, m33);
+        }
+
+        public float4x4(float4x4 m)
+        {
+            x = new float4(m.x);
+            y = new float4(m.y);
+            z = new float4(m.z);
+            w = new float4(m.w);
+        }
+
+        public float4 this[int i]
+        {
+            get
+            {
+                switch (i)
+                {
+                    case 0: return x;
+                    case 1: return y;
+                    case 2: return z;
+                    case 3: return w;
+                }
+                throw new ArgumentOutOfRangeException();
+            }
+            set
+            {
+                switch (i)
+                {
+                    case 0: x = value; return;
+                    case 1: y = value; return;
+                    case 2: z = value; return;
+                    case 3: w = value; return;
+                }
+                throw new ArgumentOutOfRangeException();
+            }
+        }
+
+        public override int GetHashCode()
+        {
+            return x.GetHashCode() ^ y.GetHashCode() ^ z.GetHashCode() ^ w.GetHashCode();
+        }
+
+        public override bool Equals(object obj)
+        {
+            float4x4 m = obj as float4x4;
+            if (m == null)
+                return false;
+
+            return this == m;
+        }
+
+        public static float4x4 operator *(float4x4 a, float4x4 b)
+        {
+            return new float4x4(a.x * b, a.y * b, a.z * b, a.w * b);
+        }
+
+        public static bool operator ==(float4x4 a, float4x4 b)
+        {
+            return (a.x == b.x && a.y == b.y && a.z == b.z && a.w == b.w);
+        }
+
+        public static bool operator !=(float4x4 a, float4x4 b)
+        {
+            return !(a == b);
+        }
+
+        public static float4x4 Inverse(float4x4 m)
+            {
+                    float4x4 d = new float4x4();
+                    //float dst = d.x.x;
+                    float[] tmp = new float[12]; // temp array for pairs
+                    float[] src = new float[16]; // array of transpose source matrix
+                    float det; // determinant
+                    // transpose matrix
+                    for (int i = 0; i < 4; i++)
+                    {
+                            src[i] = m[i].x;
+                            src[i + 4] = m[i].y;
+                            src[i + 8] = m[i].z;
+                            src[i + 12] = m[i].w;
+                    }
+                    // calculate pairs for first 8 elements (cofactors)
+                    tmp[0] = src[10] * src[15];
+                    tmp[1] = src[11] * src[14];
+                    tmp[2] = src[9] * src[15];
+                    tmp[3] = src[11] * src[13];
+                    tmp[4] = src[9] * src[14];
+                    tmp[5] = src[10] * src[13];
+                    tmp[6] = src[8] * src[15];
+                    tmp[7] = src[11] * src[12];
+                    tmp[8] = src[8] * src[14];
+                    tmp[9] = src[10] * src[12];
+                    tmp[10] = src[8] * src[13];
+                    tmp[11] = src[9] * src[12];
+                    // calculate first 8 elements (cofactors)
+                    d.x.x = tmp[0]*src[5] + tmp[3]*src[6] + tmp[4]*src[7];
+                    d.x.x -= tmp[1]*src[5] + tmp[2]*src[6] + tmp[5]*src[7];
+                    d.x.y = tmp[1]*src[4] + tmp[6]*src[6] + tmp[9]*src[7];
+                    d.x.y -= tmp[0]*src[4] + tmp[7]*src[6] + tmp[8]*src[7];
+                    d.x.z = tmp[2]*src[4] + tmp[7]*src[5] + tmp[10]*src[7];
+                    d.x.z -= tmp[3]*src[4] + tmp[6]*src[5] + tmp[11]*src[7];
+                    d.x.w = tmp[5]*src[4] + tmp[8]*src[5] + tmp[11]*src[6];
+                    d.x.w -= tmp[4]*src[4] + tmp[9]*src[5] + tmp[10]*src[6];
+                    d.y.x = tmp[1]*src[1] + tmp[2]*src[2] + tmp[5]*src[3];
+                    d.y.x -= tmp[0]*src[1] + tmp[3]*src[2] + tmp[4]*src[3];
+                    d.y.y = tmp[0]*src[0] + tmp[7]*src[2] + tmp[8]*src[3];
+                    d.y.y -= tmp[1]*src[0] + tmp[6]*src[2] + tmp[9]*src[3];
+                    d.y.z = tmp[3]*src[0] + tmp[6]*src[1] + tmp[11]*src[3];
+                    d.y.z -= tmp[2]*src[0] + tmp[7]*src[1] + tmp[10]*src[3];
+                    d.y.w = tmp[4]*src[0] + tmp[9]*src[1] + tmp[10]*src[2];
+                    d.y.w -= tmp[5]*src[0] + tmp[8]*src[1] + tmp[11]*src[2];
+                    // calculate pairs for second 8 elements (cofactors)
+                    tmp[0] = src[2]*src[7];
+                    tmp[1] = src[3]*src[6];
+                    tmp[2] = src[1]*src[7];
+                    tmp[3] = src[3]*src[5];
+                    tmp[4] = src[1]*src[6];
+                    tmp[5] = src[2]*src[5];
+                    tmp[6] = src[0]*src[7];
+                    tmp[7] = src[3]*src[4];
+                    tmp[8] = src[0]*src[6];
+                    tmp[9] = src[2]*src[4];
+                    tmp[10] = src[0]*src[5];
+                    tmp[11] = src[1]*src[4];
+                    // calculate second 8 elements (cofactors)
+                    d.z.x = tmp[0]*src[13] + tmp[3]*src[14] + tmp[4]*src[15];
+                    d.z.x -= tmp[1]*src[13] + tmp[2]*src[14] + tmp[5]*src[15];
+                    d.z.y = tmp[1]*src[12] + tmp[6]*src[14] + tmp[9]*src[15];
+                    d.z.y -= tmp[0]*src[12] + tmp[7]*src[14] + tmp[8]*src[15];
+                    d.z.z = tmp[2]*src[12] + tmp[7]*src[13] + tmp[10]*src[15];
+                    d.z.z -= tmp[3]*src[12] + tmp[6]*src[13] + tmp[11]*src[15];
+                    d.z.w = tmp[5]*src[12] + tmp[8]*src[13] + tmp[11]*src[14];
+                    d.z.w-= tmp[4]*src[12] + tmp[9]*src[13] + tmp[10]*src[14];
+                    d.w.x = tmp[2]*src[10] + tmp[5]*src[11] + tmp[1]*src[9];
+                    d.w.x-= tmp[4]*src[11] + tmp[0]*src[9] + tmp[3]*src[10];
+                    d.w.y = tmp[8]*src[11] + tmp[0]*src[8] + tmp[7]*src[10];
+                    d.w.y-= tmp[6]*src[10] + tmp[9]*src[11] + tmp[1]*src[8];
+                    d.w.z = tmp[6]*src[9] + tmp[11]*src[11] + tmp[3]*src[8];
+                    d.w.z-= tmp[10]*src[11] + tmp[2]*src[8] + tmp[7]*src[9];
+                    d.w.w = tmp[10]*src[10] + tmp[4]*src[8] + tmp[9]*src[9];
+                    d.w.w-= tmp[8]*src[9] + tmp[11]*src[10] + tmp[5]*src[8];
+                    // calculate determinant
+            det = src[0] * d.x.x + src[1] * d.x.y + src[2] * d.x.z + src[3] * d.x.w;
+                    // calculate matrix inverse
+                    det = 1/det;
+            for (int j = 0; j < 4; j++)
+                d[j] *= det;
+                    return d;
+            }
+
+        public static float4x4 MatrixRigidInverse(float4x4 m)
+        {
+            float4x4 trans_inverse = MatrixTranslation(-m.w.xyz());
+            float4x4 rot = new float4x4(m);
+            rot.w = new float4(0f, 0f, 0f, 1f);
+            return trans_inverse * MatrixTranspose(rot);
+        }
+        public static float4x4 MatrixTranspose(float4x4 m)
+        {
+            return new float4x4(m.x.x, m.y.x, m.z.x, m.w.x, m.x.y, m.y.y, m.z.y, m.w.y, m.x.z, m.y.z, m.z.z, m.w.z, m.x.w, m.y.w, m.z.w, m.w.w);
+        }
+        public static float4x4 MatrixPerspectiveFov(float fovy, float aspect, float zn, float zf)
+        {
+            float h = 1.0f / (float)Math.Tan(fovy / 2.0f); // view space height
+            float w = h / aspect; // view space width
+            return new float4x4(w, 0, 0, 0, 0, h, 0, 0, 0, 0, zf / (zn - zf), -1, 0, 0, zn * zf / (zn - zf), 0);
+        }
+        public static float4x4 MatrixTranslation(float3 t)
+        {
+            return new float4x4(1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, t.x, t.y, t.z, 1);
+        }
+        public static float4x4 MatrixRotationZ(float angle_radians)
+        {
+            float s = (float)Math.Sin(angle_radians);
+            float c = (float)Math.Cos(angle_radians);
+            return new float4x4(c, s, 0, 0, -s, c, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1);
+        }
+        public static float4x4 MatrixLookAt(float3 eye, float3 at, float3 up)
+        {
+            float4x4 m = new float4x4();
+            m.w.w = 1.0f;
+            m.w.setxyz(eye);
+            m.z.setxyz(float3.normalize(eye - at));
+            m.x.setxyz(float3.normalize(float3.cross(up, m.z.xyz())));
+            m.y.setxyz(float3.cross(m.z.xyz(), m.x.xyz()));
+            return MatrixRigidInverse(m);
+        }
+
+        public static float4x4 MatrixFromQuatVec(Quaternion q, float3 v)
+        {
+            // builds a 4x4 transformation matrix based on orientation q and translation v
+            float qx2 = q.x * q.x;
+            float qy2 = q.y * q.y;
+            float qz2 = q.z * q.z;
+
+            float qxqy = q.x * q.y;
+            float qxqz = q.x * q.z;
+            float qxqw = q.x * q.w;
+            float qyqz = q.y * q.z;
+            float qyqw = q.y * q.w;
+            float qzqw = q.z * q.w;
+
+            return new float4x4(
+                1 - 2 * (qy2 + qz2),
+                2 * (qxqy + qzqw),
+                2 * (qxqz - qyqw),
+                0,
+                2 * (qxqy - qzqw),
+                1 - 2 * (qx2 + qz2),
+                2 * (qyqz + qxqw),
+                0,
+                2 * (qxqz + qyqw),
+                2 * (qyqz - qxqw),
+                1 - 2 * (qx2 + qy2),
+                0,
+                v.x,
+                v.y,
+                v.z,
+                1.0f);
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/int3.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/int3.cs
new file mode 100644
index 0000000..9c5760d
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/int3.cs
@@ -0,0 +1,128 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class int3
+    {
+        public int x;
+        public int y;
+        public int z;
+
+        public int3()
+        {
+        }
+
+        public int3(int _x, int _y, int _z)
+        {
+            x = _x;
+            y = _y;
+            z = _z;
+        }
+
+        public int this[int i]
+        {
+            get
+            {
+                switch (i)
+                {
+                    case 0: return x;
+                    case 1: return y;
+                    case 2: return z;
+                }
+                throw new ArgumentOutOfRangeException();
+            }
+            set
+            {
+                switch (i)
+                {
+                    case 0: x = value; return;
+                    case 1: y = value; return;
+                    case 2: z = value; return;
+                }
+                throw new ArgumentOutOfRangeException();
+            }
+        }
+
+        public override int GetHashCode()
+        {
+            return x.GetHashCode() ^ y.GetHashCode() ^ z.GetHashCode();
+        }
+
+        public override bool Equals(object obj)
+        {
+            int3 i = obj as int3;
+            if (i == null)
+                return false;
+
+            return this == i;
+        }
+
+        public static bool operator ==(int3 a, int3 b)
+        {
+            // If both are null, or both are same instance, return true.
+            if (System.Object.ReferenceEquals(a, b))
+                return true;
+            // If one is null, but not both, return false.
+            if (((object)a == null) || ((object)b == null))
+                return false;
+
+            for (int i = 0; i < 3; i++)
+            {
+                if (a[i] != b[i])
+                    return false;
+            }
+            return true;
+        }
+
+        public static bool operator !=(int3 a, int3 b)
+        {
+            return !(a == b);
+        }
+
+        public static int3 roll3(int3 a)
+        {
+            int tmp = a[0];
+            a[0] = a[1];
+            a[1] = a[2];
+            a[2] = tmp;
+            return a;
+        }
+
+        public static bool isa(int3 a, int3 b)
+        {
+            return (a == b || roll3(a) == b || a == roll3(b));
+        }
+
+        public static bool b2b(int3 a, int3 b)
+        {
+            return isa(a, new int3(b[2], b[1], b[0]));
+        }
+    }
+}
diff --git a/OpenSim/Region/Physics/ConvexDecompositionDotNet/int4.cs b/OpenSim/Region/Physics/ConvexDecompositionDotNet/int4.cs
new file mode 100644
index 0000000..c2b32e5
--- /dev/null
+++ b/OpenSim/Region/Physics/ConvexDecompositionDotNet/int4.cs
@@ -0,0 +1,66 @@
+/* The MIT License
+ * 
+ * Copyright (c) 2010 Intel Corporation.
+ * All rights reserved.
+ *
+ * Based on the convexdecomposition library from 
+ * <http://codesuppository.googlecode.com> by John W. Ratcliff and Stan Melax.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+using System;
+
+namespace OpenSim.Region.Physics.ConvexDecompositionDotNet
+{
+    public class int4
+    {
+        public int x;
+        public int y;
+        public int z;
+        public int w;
+
+        public int4()
+        {
+        }
+
+        public int4(int _x, int _y, int _z, int _w)
+        {
+            x = _x;
+            y = _y;
+            z = _z;
+            w = _w;
+        }
+
+        public int this[int i]
+        {
+            get
+            {
+                switch (i)
+                {
+                    case 0: return x;
+                    case 1: return y;
+                    case 2: return z;
+                    case 3: return w;
+                }
+                throw new ArgumentOutOfRangeException();
+            }
+        }
+    }
+}