public static void MakeGlobalShadowMatrix(ref Camera camera, out Matrix globalShadowMatrix)
{
var cameraCb = camera.Constants;
ResetFrustumCorners(ref _frustumCorners);
var frustumCenter = DxVector3.Zero;
for (int i = 0; i < 8; ++i)
{
DxVector3.TransformCoordinate(ref _frustumCorners[i], ref cameraCb.Data.InverseViewProjection,
out _frustumCorners[i]);
DxVector3.Add(ref frustumCenter, ref _frustumCorners[i], out frustumCenter);
}
DxVector3.Divide(ref frustumCenter, 8.0f, out frustumCenter);
var upDir = DxVector3.Up;
var lightCameraPos = frustumCenter;
DxVector3 lookAt;
DxVector3.Subtract(ref frustumCenter, ref Direction, out lookAt);
Matrix lightView;
Matrix.LookAtLH(ref lightCameraPos, ref lookAt, ref upDir, out lightView);
DxVector3 shadowCameraPos;
//DxVector3.Multiply(ref Lighting.LightDirection, -0.5f, out shadowCameraPos);
//DxVector3.Add(ref frustumCenter, ref shadowCameraPos, out shadowCameraPos);
shadowCameraPos = frustumCenter + Direction * -0.5f;
Matrix viewMatrix;
Matrix projMatrix;
Matrix viewProjMatrix;
Matrix.OrthoOffCenterLH(-0.5f, 0.5f, -0.5f, 0.5f, 0.0f, 1.0f, out projMatrix);
Matrix.LookAtLH(ref shadowCameraPos, ref frustumCenter, ref upDir, out viewMatrix);
Matrix.Multiply(ref viewMatrix, ref projMatrix, out viewProjMatrix);
Matrix.Multiply(ref viewProjMatrix, ref _texScaleBias, out globalShadowMatrix);
}
