SDL_FlipMode.3type - Man Page

#include <SDL3/SDL_surface.h>

typedef enum SDL_FlipMode
{
    SDL_FLIP_NONE,                                                                  /**< Do not flip */
    SDL_FLIP_HORIZONTAL,                                                            /**< flip horizontally */
    SDL_FLIP_VERTICAL,                                                              /**< flip vertically */
    SDL_FLIP_HORIZONTAL_AND_VERTICAL = (SDL_FLIP_HORIZONTAL | SDL_FLIP_VERTICAL)    /**< flip horizontally and vertically (not a diagonal flip) */
} SDL_FlipMode;

This enum is available since SDL 3.2.0.