Gets a description of the constant table.
HRESULT GetDesc( D3DXCONSTANTTABLE_DESC * pDesc );
If the method succeeds, the return value is D3D_OK. If the method fails, the return value can be one of the following: D3DERR_INVALIDCALL, D3DXERR_INVALIDDATA.
Header: Declared in D3dx9shader.h.