Center directional light shadow to the cameras eye
- by Caesar
I'm currently drawing my directional light shadow using this view and projection:
XMFLOAT3 dir((float)pitch, (float)yaw, (float)roll);
XMFLOAT3 center(0.0f, 0.0f, 0.0f);
XMVECTOR lightDir = XMLoadFloat3(&dir);
XMVECTOR lightPos = radius * lightDir;
XMVECTOR targetPos = XMLoadFloat3(¢er);
XMVECTOR up = XMVectorSet(0.0f, 1.0f, 0.0f, 0.0f);
XMMATRIX V = XMMatrixLookAtLH(lightPos, targetPos, up); // This is the view
// Transform bounding sphere to light space.
XMFLOAT3 sphereCenterLS;
XMStoreFloat3(&sphereCenterLS, XMVector3TransformCoord(targetPos, V));
// Ortho frustum in light space encloses scene.
float l = sphereCenterLS.x - radius;
float b = sphereCenterLS.y - radius;
float n = sphereCenterLS.z - radius;
float r = sphereCenterLS.x + radius;
float t = sphereCenterLS.y + radius;
float f = sphereCenterLS.z + radius;
XMMATRIX P = XMMatrixOrthographicOffCenterLH(l, r, b, t, n, f); // This is the projection
Which works prefect if the center of my scene is at 0.0, 0.0, 0.0. What I would like to do is move the center of the scene relative to the cameras position. How can I do that?
