[DirectX 7 Programmer's Reference] D3DXVec2Subtract (89.2857142857143%)
Microsoft DirectX 7.0 > Direct3D > Direct3DX Utility Library [C++] > Direct3DX Utility Library Reference > Functions > Math Functions
[DirectX October 2006 Documentation] D3DXVec2Subtract (89%)
DirectX Graphics > Direct3D 9 > Reference > D3DX Reference > Functions > Math Functions