static MatrixD CreateGlobalMatrix()
{
var verticesWorldSpace = new Vector3D[8];
MatrixD invView = MyEnvironment.InvViewProjection;
Vector3D.Transform(m_cornersCS, ref invView, verticesWorldSpace);
var centroid = verticesWorldSpace.Aggregate((x, y) => x + y) / 8f;
var view = MatrixD.CreateLookAt(centroid, centroid - MyEnvironment.DirectionalLightDir, Vector3D.UnitY);
var proj = MatrixD.CreateOrthographic(1, 1, 0, 1);
return(view * proj * MyMatrixHelpers.ClipspaceToTexture);
}