public void CalcFrustumPlanes()
{
Vector3d cN = Position + CenterOfInterest * Znear;
Vector3d cF = Position + CenterOfInterest * Zfar;
double Hnear = 2.0f * Convert.ToSingle(Math.Tan(Matrix4dExtension.DegreesToRadians(fov / 2.0f)) * Znear);
double Wnear = Hnear * aspect_ratio;
double Hfar = 2.0f * Convert.ToSingle(Math.Tan(Matrix4dExtension.DegreesToRadians(fov / 2.0f)) * Zfar);
double Wfar = Hfar * aspect_ratio;
double hHnear = Hnear / 2.0f;
double hWnear = Wnear / 2.0f;
double hHfar = Hfar / 2.0f;
double hWfar = Wfar / 2.0f;
farPts[0] = cF + Up * hHfar - right * hWfar;
farPts[1] = cF - Up * hHfar - right * hWfar;
farPts[2] = cF - Up * hHfar + right * hWfar;
farPts[3] = cF + Up * hHfar + right * hWfar;
nearPts[0] = cN + Up * hHnear - right * hWnear;
nearPts[1] = cN - Up * hHnear - right * hWnear;
nearPts[2] = cN - Up * hHnear + right * hWnear;
nearPts[3] = cN + Up * hHnear + right * hWnear;
planes[0] = CPlane.FromPoints(nearPts[3], nearPts[0], farPts[0]);
planes[1] = CPlane.FromPoints(nearPts[1], nearPts[2], farPts[2]);
planes[2] = CPlane.FromPoints(nearPts[0], nearPts[1], farPts[1]);
planes[3] = CPlane.FromPoints(nearPts[2], nearPts[3], farPts[2]);
planes[4] = CPlane.FromPoints(nearPts[0], nearPts[3], nearPts[2]);
planes[5] = CPlane.FromPoints(farPts[3], farPts[0], farPts[1]);
}
public static CPlane FromPoints(Vector3d v1, Vector3d v2, Vector3d v3)
{
CPlane temp = new CPlane();
Vector3d e1 = v2 - v1;
Vector3d e2 = v3 - v1;
Vector3d v =
temp.N = Vector3d.Normalize(Vector3d.Cross(e1, e2));
temp.d = -Vector3d.Dot(temp.N, v1);
return(temp);
}