The Ecere SDK - sdk/blob - ecere/src/gfx/3D/Plane.ec

   1 namespace gfx3D;
   2
   3 import "Display"
   4
   5 public struct Line
   6 {
   7    Vector3D p0;
   8    Vector3D delta;
   9 };
  10
  11 public struct Plane
  12 {
  13    union
  14    {
  15       struct { double a, b, c; };
  16       Vector3D normal;
  17    };
  18    double d;
  19
  20    void FromPoints(Vector3D v1, Vector3D v2, Vector3D v3)
  21    {
  22       Vector3D a, b;
  23
  24       a.Subtract(v3, v1);
  25       b.Subtract(v2, v1);
  26       normal.CrossProduct(a, b);
  27       normal.Normalize(normal);
  28
  29       d = -normal.DotProduct(v1);
  30    }
  31
  32    void FromPointsf(Vector3Df v1, Vector3Df v2, Vector3Df v3)
  33    {
  34       Vector3D v1d { (double)v1.x, (double)v1.y, (double)v1.z };
  35       Vector3D v2d { (double)v2.x, (double)v2.y, (double)v2.z };
  36       Vector3D v3d { (double)v3.x, (double)v3.y, (double)v3.z };
  37       Vector3D a, b;
  38
  39       a.Subtract(v3d, v1d);
  40       b.Subtract(v2d, v1d);
  41       normal.CrossProduct(a, b);
  42       normal.Normalize(normal);
  43
  44       d = -normal.DotProduct(v1d);
  45    }
  46
  47    void MultMatrix(Plane source, Matrix inverseTranspose)
  48    {
  49       a = source.a * inverseTranspose.m[0][0] +
  50           source.b * inverseTranspose.m[1][0] +
  51           source.c * inverseTranspose.m[2][0] +
  52           source.d * inverseTranspose.m[3][0];
  53       b = source.a * inverseTranspose.m[0][1] +
  54           source.b * inverseTranspose.m[1][1] +
  55           source.c * inverseTranspose.m[2][1] +
  56           source.d * inverseTranspose.m[3][1];
  57       c = source.a * inverseTranspose.m[0][2] +
  58           source.b * inverseTranspose.m[1][2] +
  59           source.c * inverseTranspose.m[2][2] +
  60           source.d * inverseTranspose.m[3][2];
  61       d = source.a * inverseTranspose.m[0][3] +
  62           source.b * inverseTranspose.m[1][3] +
  63           source.c * inverseTranspose.m[2][3] +
  64           source.d * inverseTranspose.m[3][3];
  65    }
  66
  67    void IntersectLine(Line line, Vector3D result)
  68    {
  69       double divisor = a * line.delta.x + b * line.delta.y + c * line.delta.z;
  70
  71       result.x = (b * line.delta.y * line.p0.x - b * line.delta.x * line.p0.y +
  72                   c * line.delta.z * line.p0.x - c * line.delta.x * line.p0.z -
  73                   d * line.delta.x ) / divisor;
  74
  75       result.y = (a * line.delta.x * line.p0.y - a * line.delta.y * line.p0.x +
  76                   c * line.delta.z * line.p0.y - c * line.delta.y * line.p0.z -
  77                   d * line.delta.y ) / divisor;
  78
  79       result.z = (a * line.delta.x * line.p0.z - a * line.delta.z * line.p0.x +
  80                   b * line.delta.y * line.p0.z - b * line.delta.z * line.p0.y -
  81                   d * line.delta.z ) / divisor;
  82    }
  83
  84    void IntersectLinef(Line line, Vector3Df result)
  85    {
  86       double divisor = a * line.delta.x + b * line.delta.y + c * line.delta.z;
  87
  88       result.x = (float)((b * line.delta.y * line.p0.x - b * line.delta.x * line.p0.y +
  89                   c * line.delta.z * line.p0.x - c * line.delta.x * line.p0.z -
  90                   d * line.delta.x ) / divisor);
  91
  92       result.y = (float)((a * line.delta.x * line.p0.y - a * line.delta.y * line.p0.x +
  93                   c * line.delta.z * line.p0.y - c * line.delta.y * line.p0.z -
  94                   d * line.delta.y ) / divisor);
  95
  96       result.z = (float)((a * line.delta.x * line.p0.z - a * line.delta.z * line.p0.x +
  97                   b * line.delta.y * line.p0.z - b * line.delta.z * line.p0.y -
  98                   d * line.delta.z ) / divisor);
  99    }
 100
 101    void FromPointNormal(Vector3D normal, Vector3D point)
 102    {
 103       this.normal = normal;
 104       d = -(normal.x * point.x + normal.y * point.y + normal.z * point.z);
 105    }
 106 };