Hollow prims (box only), thanks Gerard! Enjoy

1 files changed, 279 insertions, 0 deletions

diff --git a/OpenSim/Region/Physics/OdePlugin/Meshing\/HelperTypes.cs b/OpenSim/Region/Physics/OdePlugin/Meshing\/HelperTypes.cs
new file mode 100644
index 0000000..3d40c04
--- /dev/null
+++ b/OpenSim/Region/Physics/OdePlugin/Meshing\/HelperTypes.cs
@@ -0,0 +1,279 @@
+using System;
+using System.Globalization;
+using System.Diagnostics;
+using System.Collections.Generic;
+
+using OpenSim.Region.Physics.Manager;
+
+public class Vertex : IComparable<Vertex>
+{
+    public String name;
+    public PhysicsVector point;
+
+    public Vertex(String name, float x, float y, float z)
+    {
+        this.name = name;
+        point = new PhysicsVector(x, y, z);
+    }
+
+    public int CompareTo(Vertex other)
+    {
+        if (point.X < other.point.X)
+            return -1;
+
+        if (point.X > other.point.X)
+            return 1;
+
+        if (point.Y < other.point.Y)
+            return -1;
+
+        if (point.Y > other.point.Y)
+            return 1;
+
+        if (point.Z < other.point.Z)
+            return -1;
+
+        if (point.Z > other.point.Z)
+            return 1;
+
+        return 0;
+    }
+
+    public static bool operator >(Vertex me, Vertex other)
+    {
+        return me.CompareTo(other) > 0;
+    }
+
+    public static bool operator <(Vertex me, Vertex other)
+    {
+        return me.CompareTo(other) < 0;
+    }
+
+
+}
+
+public class Simplex : IComparable<Simplex>
+{
+    public Vertex v1;
+    public Vertex v2;
+
+    public Simplex(Vertex _v1, Vertex _v2)
+    {
+        // Presort indices to make sorting (comparing) easier
+        if (_v1 > _v2)
+        {
+            v1 = _v1;
+            v2 = _v2;
+        }
+        else
+        {
+            v1 = _v2;
+            v2 = _v1;
+        }
+    }
+
+    public int CompareTo(Simplex other)
+    {
+        if (v1 > other.v1)
+        {
+            return 1;
+        }
+        if (v1 < other.v1)
+        {
+            return -1;
+        }
+
+        if (v2 > other.v2)
+        {
+            return 1;
+        }
+        if (v2 < other.v2)
+        {
+            return -1;
+        }
+
+        return 0;
+    }
+
+};
+
+public class Triangle
+{
+    public Vertex v1;
+    public Vertex v2;
+    public Vertex v3;
+
+    float radius_square;
+    float cx;
+    float cy;
+
+    public Triangle(Vertex _v1, Vertex _v2, Vertex _v3)
+    {
+        v1 = _v1;
+        v2 = _v2;
+        v3 = _v3;
+
+        CalcCircle();
+    }
+
+    public bool isInCircle(float x, float y)
+    {
+        float dx, dy;
+        float dd;
+
+        dx = x - this.cx;
+        dy = y - this.cy;
+
+        dd = dx * dx + dy * dy;
+        if (dd < this.radius_square)
+            return true;
+        else
+            return false;
+    }
+
+
+    void CalcCircle()
+    {
+        // Calculate the center and the radius of a circle given by three points p1, p2, p3
+        // It is assumed, that the triangles vertices are already set correctly
+        double p1x, p2x, p1y, p2y, p3x, p3y;
+
+        // Deviation of this routine: 
+        // A circle has the general equation (M-p)^2=r^2, where M and p are vectors
+        // this gives us three equations f(p)=r^2, each for one point p1, p2, p3
+        // putting respectively two equations together gives two equations
+        // f(p1)=f(p2) and f(p1)=f(p3)
+        // bringing all constant terms to one side brings them to the form
+        // M*v1=c1 resp.M*v2=c2 where v1=(p1-p2) and v2=(p1-p3) (still vectors)
+        // and c1, c2 are scalars (Naming conventions like the variables below)
+        // Now using the equations that are formed by the components of the vectors
+        // and isolate Mx lets you make one equation that only holds My
+        // The rest is straight forward and eaasy :-)
+        // 
+
+        /* helping variables for temporary results */
+        double c1, c2;
+        double v1x, v1y, v2x, v2y;
+
+        double z, n;
+
+        double rx, ry;
+
+        // Readout the three points, the triangle consists of
+        p1x = v1.point.X;
+        p1y = v1.point.Y;
+
+        p2x = v2.point.X;
+        p2y = v2.point.Y;
+
+        p3x = v3.point.X;
+        p3y = v3.point.Y;
+
+        /* calc helping values first */
+        c1 = (p1x * p1x + p1y * p1y - p2x * p2x - p2y * p2y) / 2;
+        c2 = (p1x * p1x + p1y * p1y - p3x * p3x - p3y * p3y) / 2;
+
+        v1x = p1x - p2x;
+        v1y = p1y - p2y;
+
+        v2x = p1x - p3x;
+        v2y = p1y - p3y;
+
+        z = (c1 * v2x - c2 * v1x);
+        n = (v1y * v2x - v2y * v1x);
+
+        if (n == 0.0)   // This is no triangle, i.e there are (at least) two points at the same location
+        {
+            radius_square = 0.0f;
+            return;
+        }
+
+        this.cy = (float)(z / n);
+
+        if (v2x != 0.0)
+        {
+            this.cx = (float)((c2 - v2y * this.cy) / v2x);
+        }
+        else if (v1x != 0.0)
+        {
+            this.cx = (float)((c1 - v1y * this.cy) / v1x);
+        }
+        else
+        {
+            Debug.Assert(false, "Malformed triangle"); /* Both terms zero means nothing good */
+        }
+
+        rx = (p1x - this.cx);
+        ry = (p1y - this.cy);
+
+        this.radius_square = (float)(rx * rx + ry * ry);
+
+    }
+
+    public List<Simplex> GetSimplices()
+    {
+        List<Simplex> result = new List<Simplex>();
+        Simplex s1 = new Simplex(v1, v2);
+        Simplex s2 = new Simplex(v2, v3);
+        Simplex s3 = new Simplex(v3, v1);
+
+        result.Add(s1);
+        result.Add(s2);
+        result.Add(s3);
+
+        return result;
+    }
+
+    public override String ToString()
+    {
+
+        NumberFormatInfo nfi = new NumberFormatInfo();
+        nfi.CurrencyDecimalDigits = 2;
+        nfi.CurrencyDecimalSeparator = ".";
+
+        String s1 = "<" + v1.point.X.ToString(nfi) + "," + v1.point.Y.ToString(nfi) + "," + v1.point.Z.ToString(nfi) + ">";
+        String s2 = "<" + v2.point.X.ToString(nfi) + "," + v2.point.Y.ToString(nfi) + "," + v2.point.Z.ToString(nfi) + ">";
+        String s3 = "<" + v3.point.X.ToString(nfi) + "," + v3.point.Y.ToString(nfi) + "," + v3.point.Z.ToString(nfi) + ">";
+
+        return s1 + ";" + s2 + ";" + s3;
+
+    }
+
+    public PhysicsVector getNormal()
+    {
+        // Vertices
+
+        // Vectors for edges
+        PhysicsVector e1;
+        PhysicsVector e2;
+
+        e1 = new PhysicsVector(v1.point.X - v2.point.X, v1.point.Y - v2.point.Y, v1.point.Z - v2.point.Z);
+        e2 = new PhysicsVector(v1.point.X - v3.point.X, v1.point.Y - v3.point.Y, v1.point.Z - v3.point.Z);
+
+        // Cross product for normal
+        PhysicsVector n = new PhysicsVector();
+        float nx, ny, nz;
+        n.X = e1.Y * e2.Z - e1.Z * e2.Y;
+        n.Y = e1.Z * e2.X - e1.X * e2.Z;
+        n.Z = e1.X * e2.Y - e1.Y * e2.X;
+
+        // Length
+        float l = (float)Math.Sqrt(n.X * n.X + n.Y * n.Y + n.Z * n.Z);
+
+        // Normalized "normal"
+        n.X /= l;
+        n.Y /= l;
+        n.Z /= l;
+
+        return n;
+    }
+
+    public void invertNormal()
+    {
+        Vertex vt;
+        vt = v1;
+        v1 = v2;
+        v2 = vt;
+    }
+}
+