public void PrepareProjection(SceneNode root, PerspectiveCameraNode cam, int shadowMapIdx)
{
Matrix4 proj = GetSliceFrustumProjection(shadowMapIdx, cam);
Vector4 shadowOffsetAndScale = _shadowCascades[shadowMapIdx].PrepareProjection(root, proj, cam, this);
_shadowParameters.SetShadowOffsetAndScale(shadowMapIdx, shadowOffsetAndScale);
}
private Matrix4 GetSliceFrustumProjection(int shadowMapIdx, PerspectiveCameraNode cam)
{
float nearPlane = cam.FarPlane - cam.NearPlane;
if (shadowMapIdx > 0)
{
for (int i = _shadowCascades.Count - 1; i > shadowMapIdx - 1; i--)
{
nearPlane /= 4f;
}
}
else
{
nearPlane = cam.NearPlane;
}
float farPlane = cam.FarPlane - cam.NearPlane;
for (int i = _shadowCascades.Count - 1; i > shadowMapIdx; i--)
{
farPlane /= 4f;
}
return(Matrix4.PerspectiveFovRH(cam.Fov, cam.Aspect, nearPlane, farPlane));
}
