private Ray ViewportToRayMouse(int x, int y)
{
Matrix4 cameraProjectionMatrix = mCamera.GetProjMatrix();
Matrix4 cameraWorldMatrix = mCamera.GetWorldMatrix();
Vector3 direction;
// convert to view space
direction.X = ((2.0f * x / mWidth - 1)) / cameraProjectionMatrix.M11;
direction.Y = -((2.0f * y / mHeight - 1)) / cameraProjectionMatrix.M22;
direction.Z = 1.0f / cameraProjectionMatrix.M33;
direction = Vector4.Transform(new Vector4(direction.X, direction.Y, direction.Z, 0.0f), cameraWorldMatrix).Xyz;
Vector3 rayPos = cameraWorldMatrix.Row3.Xyz;
Vector3 rayDir = direction.Normalized();
return(new Ray(rayPos, rayDir));
}
