Initiate the rendering of a parabolic environment map.
HRESULT BeginParabolic( LPDIRECT3DTEXTURE9 pTexZPos, LPDIRECT3DTEXTURE9 pTexZNeg );
If the function succeeds, the return value is D3D_OK. If the function fails, the return value can be one of the following: D3DERR_INVALIDCALL.
E_FAILSee ID3DXRenderToEnvMap::Face to draw the faces.
Header: Declared in D3dx9core.h.