SDL_GetWindowOpacity - Get the opacity of a window.

       This function is available since SDL 3.2.0.

       If transparency isn't supported on this platform, opacity will be returned as 1.0f without error.

window the window to get the current opacity value from.

       Defined in SDL3/SDL_video.h

       SDL_GetWindowOpacity - Get the opacity of a window.

       Returns  the  opacity, (0.0f - transparent, 1.0f - opaque), or -1.0f on failure; call SDL_GetError () for
       more information.

•(3), SDL_SetWindowOpacity(3)

Simple Directmedia Layer                           SDL 3.2.10                            SDL_GetWindowOpacity(3)

#include"SDL3/SDL.h"floatSDL_GetWindowOpacity(SDL_Window*window);

       This function should only be called on the main thread.