public void CalcFrustumPlanes()
{
Vector3 cN = Position + CenterOfInterest * Znear;
Vector3 cF = Position + CenterOfInterest * Zfar;
float Hnear = 2.0f * Convert.ToSingle(Math.Tan(Matrix4Extension.DegreesToRadians(fov / 2.0f)) * Znear);
float Wnear = Hnear * aspect_ratio;
float Hfar = 2.0f * Convert.ToSingle(Math.Tan(Matrix4Extension.DegreesToRadians(fov / 2.0f)) * Zfar);
float Wfar = Hfar * aspect_ratio;
float hHnear = Hnear / 2.0f;
float hWnear = Wnear / 2.0f;
float hHfar = Hfar / 2.0f;
float 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(Vector3 v1, Vector3 v2, Vector3 v3)
{
CPlane temp = new CPlane();
Vector3 e1 = v2 - v1;
Vector3 e2 = v3 - v1;
Vector3 v =
temp.N = Vector3.Normalize(Vector3.Cross(e1, e2));
temp.d = -Vector3.Dot(temp.N, v1);
return(temp);
}
