Gets the vertex declaration.
HRESULT GetDeclaration( LPD3DVERTEXELEMENT9 pDeclaration[MAX_FVF_DECL_SIZE] );
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, E_OUTOFMEMORY.
The array of elements includes the D3DDECL_END macro, which ends the declaration.
Header: Declared in D3dx9mesh.h.