How to swap multiple OpenGL windows?


#1
SDL_GL_MakeCurrent(window1, context1);
SDL_GL_SetSwapInterval(1);
RenderWindow1();

SDL_GL_MakeCurrent(window2, context1);
SDL_GL_SetSwapInterval(1);
RenderWindow2();

SDL_GL_SwapWindow(window1);
SDL_GL_SwapWindow(window2);

How does swapping work in this case? Won’t each SDL_GL_SwapWindow wait for V-Sync, halving the frame rate? Should I select one of the windows as the “primary window” and only set SDL_GL_SetSwapInterval(1) on its OpenGL context?