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diff --git a/OpenSim/Region/Physics/BulletSNPlugin/BSTerrainMesh.cs b/OpenSim/Region/Physics/BulletSNPlugin/BSTerrainMesh.cs
new file mode 100644
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+++ b/OpenSim/Region/Physics/BulletSNPlugin/BSTerrainMesh.cs
@@ -0,0 +1,267 @@
+/*
+ * Copyright (c) Contributors, http://opensimulator.org/
+ * See CONTRIBUTORS.TXT for a full list of copyright holders.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyrightD
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the OpenSimulator Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+using OpenSim.Framework;
+using OpenSim.Region.Framework;
+using OpenSim.Region.CoreModules;
+using OpenSim.Region.Physics.Manager;
+
+using Nini.Config;
+using log4net;
+
+using OpenMetaverse;
+
+namespace OpenSim.Region.Physics.BulletSNPlugin
+{
+public sealed class BSTerrainMesh : BSTerrainPhys
+{
+    static string LogHeader = "[BULLETSIM TERRAIN MESH]";
+
+    private float[] m_savedHeightMap;
+    int m_sizeX;
+    int m_sizeY;
+
+    BulletShape m_terrainShape;
+    BulletBody m_terrainBody;
+
+    public BSTerrainMesh(BSScene physicsScene, Vector3 regionBase, uint id, Vector3 regionSize) 
+        : base(physicsScene, regionBase, id)
+    {
+    }
+
+    public BSTerrainMesh(BSScene physicsScene, Vector3 regionBase, uint id /* parameters for making mesh */)
+        : base(physicsScene, regionBase, id)
+    {
+    }
+
+    // Create terrain mesh from a heightmap.
+    public BSTerrainMesh(BSScene physicsScene, Vector3 regionBase, uint id, float[] initialMap, 
+                                                    Vector3 minCoords, Vector3 maxCoords)
+        : base(physicsScene, regionBase, id)
+    {
+        int indicesCount;
+        int[] indices;
+        int verticesCount;
+        float[] vertices;
+
+        m_savedHeightMap = initialMap;
+
+        m_sizeX = (int)(maxCoords.X - minCoords.X);
+        m_sizeY = (int)(maxCoords.Y - minCoords.Y);
+
+        if (!BSTerrainMesh.ConvertHeightmapToMesh(PhysicsScene, initialMap,
+                            m_sizeX, m_sizeY,
+                            (float)m_sizeX, (float)m_sizeY,
+                            Vector3.Zero, 1.0f,
+                            out indicesCount, out indices, out verticesCount, out vertices))
+        {
+            // DISASTER!!
+            PhysicsScene.DetailLog("{0},BSTerrainMesh.create,failedConversionOfHeightmap", ID);
+            PhysicsScene.Logger.ErrorFormat("{0} Failed conversion of heightmap to mesh! base={1}", LogHeader, TerrainBase);
+            // Something is very messed up and a crash is in our future.
+            return;
+        }
+        PhysicsScene.DetailLog("{0},BSTerrainMesh.create,meshed,indices={1},indSz={2},vertices={3},vertSz={4}", 
+                                ID, indicesCount, indices.Length, verticesCount, vertices.Length);
+
+        m_terrainShape = new BulletShape(BulletSimAPI.CreateMeshShape2(PhysicsScene.World.ptr,
+                                                    indicesCount, indices, verticesCount, vertices),
+                                        BSPhysicsShapeType.SHAPE_MESH);
+        if (!m_terrainShape.HasPhysicalShape)
+        {
+            // DISASTER!!
+            PhysicsScene.DetailLog("{0},BSTerrainMesh.create,failedCreationOfShape", ID);
+            physicsScene.Logger.ErrorFormat("{0} Failed creation of terrain mesh! base={1}", LogHeader, TerrainBase);
+            // Something is very messed up and a crash is in our future.
+            return;
+        }
+
+        Vector3 pos = regionBase;
+        Quaternion rot = Quaternion.Identity;
+
+        m_terrainBody = new BulletBody(id, BulletSimAPI.CreateBodyWithDefaultMotionState2( m_terrainShape.ptr, ID, pos, rot));
+        if (!m_terrainBody.HasPhysicalBody)
+        {
+            // DISASTER!!
+            physicsScene.Logger.ErrorFormat("{0} Failed creation of terrain body! base={1}", LogHeader, TerrainBase);
+            // Something is very messed up and a crash is in our future.
+            return;
+        }
+
+        // Set current terrain attributes
+        BulletSimAPI.SetFriction2(m_terrainBody.ptr, BSParam.TerrainFriction);
+        BulletSimAPI.SetHitFraction2(m_terrainBody.ptr, BSParam.TerrainHitFraction);
+        BulletSimAPI.SetRestitution2(m_terrainBody.ptr, BSParam.TerrainRestitution);
+        BulletSimAPI.SetCollisionFlags2(m_terrainBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
+
+        // Static objects are not very massive.
+        BulletSimAPI.SetMassProps2(m_terrainBody.ptr, 0f, Vector3.Zero);
+
+        // Put the new terrain to the world of physical objects
+        BulletSimAPI.AddObjectToWorld2(PhysicsScene.World.ptr, m_terrainBody.ptr, pos, rot);
+
+        // Redo its bounding box now that it is in the world
+        BulletSimAPI.UpdateSingleAabb2(PhysicsScene.World.ptr, m_terrainBody.ptr);
+
+        m_terrainBody.collisionType = CollisionType.Terrain;
+        m_terrainBody.ApplyCollisionMask();
+
+        // Make it so the terrain will not move or be considered for movement.
+        BulletSimAPI.ForceActivationState2(m_terrainBody.ptr, ActivationState.DISABLE_SIMULATION);
+    }
+
+    public override void Dispose()
+    {
+        if (m_terrainBody.HasPhysicalBody)
+        {
+            BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, m_terrainBody.ptr);
+            // Frees both the body and the shape.
+            BulletSimAPI.DestroyObject2(PhysicsScene.World.ptr, m_terrainBody.ptr);
+        }
+    }
+
+    public override float GetTerrainHeightAtXYZ(Vector3 pos)
+    {
+        // For the moment use the saved heightmap to get the terrain height.
+        // TODO: raycast downward to find the true terrain below the position.
+        float ret = BSTerrainManager.HEIGHT_GETHEIGHT_RET;
+
+        int mapIndex = (int)pos.Y * m_sizeY + (int)pos.X;
+        try
+        {
+            ret = m_savedHeightMap[mapIndex];
+        }
+        catch
+        {
+            // Sometimes they give us wonky values of X and Y. Give a warning and return something.
+            PhysicsScene.Logger.WarnFormat("{0} Bad request for terrain height. terrainBase={1}, pos={2}",
+                                                LogHeader, TerrainBase, pos);
+            ret = BSTerrainManager.HEIGHT_GETHEIGHT_RET;
+        }
+        return ret;
+    }
+
+    // The passed position is relative to the base of the region.
+    public override float GetWaterLevelAtXYZ(Vector3 pos)
+    {
+        return PhysicsScene.SimpleWaterLevel;
+    }
+
+    // Convert the passed heightmap to mesh information suitable for CreateMeshShape2().
+    // Return 'true' if successfully created.
+    public static bool ConvertHeightmapToMesh(
+                                BSScene physicsScene,
+                                float[] heightMap, int sizeX, int sizeY,    // parameters of incoming heightmap
+                                float extentX, float extentY,               // zero based range for output vertices
+                                Vector3 extentBase,                         // base to be added to all vertices
+                                float magnification,                        // number of vertices to create between heightMap coords
+                                out int indicesCountO, out int[] indicesO,
+                                out int verticesCountO, out float[] verticesO)
+    {
+        bool ret = false;
+
+        int indicesCount = 0;
+        int verticesCount = 0;
+        int[] indices = new int[0];
+        float[] vertices = new float[0];
+
+        // Simple mesh creation which assumes magnification == 1.
+        // TODO: do a more general solution that scales, adds new vertices and smoothes the result.
+
+        // Create an array of vertices that is sizeX+1 by sizeY+1 (note the loop
+        //    from zero to <= sizeX). The triangle indices are then generated as two triangles
+        //    per heightmap point. There are sizeX by sizeY of these squares. The extra row and
+        //    column of vertices are used to complete the triangles of the last row and column
+        //    of the heightmap.
+        try
+        {
+            // One vertice per heightmap value plus the vertices off the top and bottom edge.
+            int totalVertices = (sizeX + 1) * (sizeY + 1);
+            vertices = new float[totalVertices * 3];
+            int totalIndices = sizeX * sizeY * 6;
+            indices = new int[totalIndices];
+
+            float magX = (float)sizeX / extentX;
+            float magY = (float)sizeY / extentY;
+            physicsScene.DetailLog("{0},BSTerrainMesh.ConvertHeightMapToMesh,totVert={1},totInd={2},extentBase={3},magX={4},magY={5}",
+                                    BSScene.DetailLogZero, totalVertices, totalIndices, extentBase, magX, magY);
+            float minHeight = float.MaxValue;
+            // Note that sizeX+1 vertices are created since there is land between this and the next region.
+            for (int yy = 0; yy <= sizeY; yy++)
+            {
+                for (int xx = 0; xx <= sizeX; xx++)     // Hint: the "<=" means we go around sizeX + 1 times
+                {
+                    int offset = yy * sizeX + xx;
+                    // Extend the height with the height from the last row or column
+                    if (yy == sizeY) offset -= sizeX;
+                    if (xx == sizeX) offset -= 1;
+                    float height = heightMap[offset];
+                    minHeight = Math.Min(minHeight, height);
+                    vertices[verticesCount + 0] = (float)xx * magX + extentBase.X;
+                    vertices[verticesCount + 1] = (float)yy * magY + extentBase.Y;
+                    vertices[verticesCount + 2] = height + extentBase.Z;
+                    verticesCount += 3;
+                }
+            }
+            verticesCount = verticesCount / 3;
+
+            for (int yy = 0; yy < sizeY; yy++)
+            {
+                for (int xx = 0; xx < sizeX; xx++)
+                {
+                    int offset = yy * (sizeX + 1) + xx;
+                    // Each vertices is presumed to be the upper left corner of a box of two triangles
+                    indices[indicesCount + 0] = offset;
+                    indices[indicesCount + 1] = offset + 1;
+                    indices[indicesCount + 2] = offset + sizeX + 1; // accounting for the extra column
+                    indices[indicesCount + 3] = offset + 1;
+                    indices[indicesCount + 4] = offset + sizeX + 2;
+                    indices[indicesCount + 5] = offset + sizeX + 1;
+                    indicesCount += 6;
+                }
+            }
+
+            ret = true;
+        }
+        catch (Exception e)
+        {
+            physicsScene.Logger.ErrorFormat("{0} Failed conversion of heightmap to mesh. For={1}/{2}, e={3}",
+                                                LogHeader, physicsScene.RegionName, extentBase, e);
+        }
+
+        indicesCountO = indicesCount;
+        indicesO = indices;
+        verticesCountO = verticesCount;
+        verticesO = vertices;
+
+        return ret;
+    }
+}
+}