IDirect3DDevice9Ex::GetDisplayMode

DX9 vtable[8] → HRESULT

IDirect3DDevice9Ex::GetDisplayMode is a method of the COM interface IDirect3DDevice9Ex in Direct3D 9. Its function pointer sits at vtable index 8 — the zero-based slot in that interface's virtual method table, counted from QueryInterface and including every entry inherited from a base interface. It takes 2 parameters (swapchain_idx, mode) and returns HRESULT.

COM methods are reached through that table rather than by an exported name, so the slot index is what a wrapper, an interface hook or a disassembly listing has to resolve against. The parameter order and types below are the ones this interface declares.