IDirect3DRMTexture::SetDecalOrigin
HRESULT SetDecalOrigin(LONG lX, LONG lY);
Sets the origin of the decal as an offset from the top left of the decal.
·Returns D3DRM_OK if successful, or an error otherwise. For a list of possible return codes, see Direct3D Retained-Mode Return Values.
lX and lY
New origin, in decal coordinates, for the decal. The default origin is [0, 0].
The decal's origin is mapped to its frame's position when rendering. For example, the origin of a decal of a cross would be set to the middle of the decal, and the origin of an arrow pointing down would be set to midway along the bottom edge.