Some important functions of SDL

/** Restart one of the threads that are waiting on the condition variable, * @ return 0 or-1 on error. */extern declspec int sdlcall sdl_condsignal (sdl_cond * Cond);/** wait on the condition variable, unlocking the provided mutex. * The mutex must be locked before entering this function! * The mutex is re-locked once the condition variable is signaled. * @ return 0 when it is signaled, or-1 on error. */extern declspec int sdlcall sdl_condwait (sdl_cond * cond, sdl_mutex * MUT);/* The ratio of width to height directly affects the video display ratio. For example, width * = 2; then the width is changed to the original 1/2. If the height * = 2 is the same, the screen after the video is not changed to the original 1/2. */Extern declspec sdl_overlay * sdlcall sdl_createyuvoverlay (INT width, int height, uint32 format, sdl_surface * display);/*** srcw, srch: width and height of the Source Video dstw and DTH: width and height of the target video **/struct swscontext * sws_getcontext (INT srcw, int srch, int srcformat, int dstw, int DTH, int dstformat, int flags, swsfilter * srcfilter, swsfilter * dstfilter, double * PARAM );

/*** Set up a video mode with the specified width, height and bits-per-pixel. ** if 'bpp 'is 0, it is treated as the current display bits per pixel. ** if sdl_anyformat is set in 'flags ', the SDL library will try to set the * Requested bits-per-pixel, but will return whatever video pixel format is * available. the default is to emulate the requested pixel format if it * is not natively available. ** if sdl_hwsurface is set in 'flags ', the video surface will be placed in * video memory, if possible, and you may have to call sdl_locksurface () * In order to access the raw framebuffer. otherwise, the video surface * will be created in system memory. ** if sdl_asyncb1_is set in 'flags ', SDL will try to perform rectangle * updates asynchronously, but you must always lock before accessing pixels. * SDL will wait for updates to complete before returning from the lock. ** if sdl_hwpalette is set in 'flags ', the SDL library will guarantee * that the colors set by sdl_setcolors () will be the colors you get. * otherwise, in 8-Bit mode, sdl_setcolors () may not be able to set all * of the colors exactly the way they are requested, and you shoshould look * at the video surface structure to determine the actual palette. * If SDL cannot guarantee that the colors you request can be set, * I. e. if the colormap is shared, then the video surface may be created * under emulation in system memory, overriding the sdl_hwsurface flag. ** if sdl_fullscreen is set in 'flags ', the SDL library will try to set * A fullscreen video mode. the default is to create a custom wed mode * if the current graphics system has a window manager. * If the SDL library is able to set a fullscreen video mode, this flag * will be set in the surface that is returned. ** if sdl_doublebuf is set in 'flags ', the SDL library will try to set up * two surfaces in video memory and swap between them when you call * sdl_flip (). this is usually slower than the normal single-buffering * scheme, but prevents "Tearing" Artifacts Caused by modifying video * memory while the monitor is refreshing. it shoshould only be used by * applications that redraw the entire Screen on every update. ** if sdl_resizable is set in 'flags ', the SDL library will allow the * window manager, if any, to resize the window at runtime. when this * occurs, SDL will send a sdl_videoresize event to you application, * and you must respond to the event by re-calling sdl_setvideomode () * With the requested size (or another size that suits the application ). ** if sdl_noframe is set in 'flags ', the SDL library will create a window * without any title bar or frame decoration. fullscreen video modes have * this flag set automatically. ** this function returns the video framebuffer surface, or null if it fails. ** if you rely on functionality provided by certain video flags, check the * flags of the returned surface to make sure that functionality is available. * SDL will fall back to CED functionality if the exact flags you wanted * are not available. * // * change the int width and INT height parameters of the function, the size and size of the frame */extern declspec sdl_surface * sdlcall sdl_setvideomode (INT width, int height, int bpp, uint32 flags );