/// <summary>
/// Crea una instancia de HFrustum a partir de una luz de tipo spot
/// </summary>
public Frustum(SpotLight spot)
{
planes = new List <Plane>(6);
for (int i = 0; i < 6; i++)
{
planes.Add(new Plane());
}
UpdateFromSpotLight(spot);
}
/// <summary>
/// Actualiza el frustum en base a una luz spot
/// </summary>
public void UpdateFromSpotLight(SpotLight spot)
{
//System.Diagnostics.Debug.Assert(planes.Count == 6);
Matrix viewProjection = Matrix.Invert(spot.LocalMatrix) * spot.ProjectorPerspective;
planes.Clear();
float A, B, C, D;
Plane p;
// Left clipping plane
A = -(viewProjection.M14 + viewProjection.M11);
B = -(viewProjection.M24 + viewProjection.M21);
C = -(viewProjection.M34 + viewProjection.M31);
D = -(viewProjection.M44 + viewProjection.M41);
p = new Plane(A, B, C, D);
p.Normalize();
planes.Add(p);
// Right clipping plane
A = -(viewProjection.M14 - viewProjection.M11);
B = -(viewProjection.M24 - viewProjection.M21);
C = -(viewProjection.M34 - viewProjection.M31);
D = -(viewProjection.M44 - viewProjection.M41);
p = new Plane(A, B, C, D);
p.Normalize();
planes.Add(p);
// Top clipping plane
A = -(viewProjection.M14 - viewProjection.M12);
B = -(viewProjection.M24 - viewProjection.M22);
C = -(viewProjection.M34 - viewProjection.M32);
D = -(viewProjection.M44 - viewProjection.M42);
p = new Plane(A, B, C, D);
p.Normalize();
planes.Add(p);
// Bottom clipping plane
A = -(viewProjection.M14 + viewProjection.M12);
B = -(viewProjection.M24 + viewProjection.M22);
C = -(viewProjection.M34 + viewProjection.M32);
D = -(viewProjection.M44 + viewProjection.M42);
p = new Plane(A, B, C, D);
p.Normalize();
planes.Add(p);
// Near clipping plane
A = -(viewProjection.M14 + viewProjection.M13);
B = -(viewProjection.M24 + viewProjection.M23);
C = -(viewProjection.M34 + viewProjection.M33);
D = -(viewProjection.M44 + viewProjection.M43);
p = new Plane(A, B, C, D);
p.Normalize();
planes.Add(p);
// Far clipping plane
A = -(viewProjection.M14 - viewProjection.M13);
B = -(viewProjection.M24 - viewProjection.M23);
C = -(viewProjection.M34 - viewProjection.M33);
D = -(viewProjection.M44 - viewProjection.M43);
p = new Plane(A, B, C, D);
p.Normalize();
planes.Add(p);
// Create device clipping planes
//CreateDeviceClipPlanes();
}