SDL_GetDirect3D9AdapterIndex - Get the D3D9 adapter index that matches the specified display.

       This function is available since SDL 3.2.0.

Simple Directmedia Layer                           SDL 3.2.20                    SDL_GetDirect3D9AdapterIndex(3)

       The returned adapter index can be passed to IDirect3D9::CreateDevice and controls on which monitor a full
       screen application will appear.

displayID
              the instance of the display to query.

       SDL_GetDirect3D9AdapterIndex - Get the D3D9 adapter index that matches the specified display.

       for more information.

#include<SDL3/SDL_system.h>intSDL_GetDirect3D9AdapterIndex(SDL_DisplayIDdisplayID);