Like the IDirect3D2 interface, the IDirect3D3 interface supports the DrawPrimitive style of Direct3D programming. In addition, the IDirect3D3 interface extends the functionality of the DrawPrimitive-style programming by introducing the IDirect3DDevice3 interface. This new interface supports flexible vertex formats, vertex buffers, and new texturing capabilities. For additional information, see Vertex Formats, Textures, Vertex Buffers and Rendering.
Applications obtain a pointer to the IDirect3D3 interface from a DirectDraw object using the QueryInterface method. For details, see Retrieving an IDirect3D3 Interface.