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Sdl_waitevent Example


The value returned by the callback function will become the new timer interval. You will add more events and will never get your screen updated. Is this expected behaviour of SDL_WaitEvent? return 0; } Next.

Apparently in SDL 2, they changed it so that SDL_WaitEvent just loops until an event takes place rather than passing control back to the OS. And, if you want to map '1' and Shift-'1' to different things, it might get confusing for those poor french users - for them, pressing '1' always implies pressing Shift, too... You'd want SDL_PollEvent: 1
while(programrunning) { // keep looping and processing events here until there are no more events to process while( SDL_PollEvent(&evt) ) { switch(evt.type) { case SDL_QUIT: programrunning = If you think that is this a hack (even an evil one), I'll agrre.

Sdl_waitevent Example

There also appears to be a bug in the timer logic - it 'skips' every now and then if a tick happens at a certain place in the timer thread loop. Don't call any SDL functions from a timer callback. Which means that if there are no events to process your program will wait until there is an event.

Updates: SDL_GetMouseState and SDL_GetKeyState are only updated when you call SDL_PumpEvents. Otherwise I'd limit myself as much as possible. On Sun, May 22, 2016 at 10:26 AM, Mark Sibly wrote: Quote: Hi, Windows 10 SDL2 user here! Sdl Wait Event Timeout To handle mouse wheel events, you actually have to handle mouse button events and figure out how far you want to move based on the number of events you get Detect

Poor CPU... Sdl_pollevent Not Working A slightly more complex event loop is shown in Figure4, "SDL keyboard event loop.". After all events have been processed, a message is printed at line 15. How can i set a break (pause) in my game?

Yes SDL_WaitEvent is essentially a blocking function. Sdl_pollevent Blocking Everybody who is using the sym directly, you need to rewrite your code to look at the unicode member of the key event, otherwise your program won't work with non-english keyboards. Not only is the modifier state only correct for the time the event is processed, but you won't correctly handle international keyboard input. Further unfortunately, SDL_PumpEvents must be run on the thread that initialized the video subsystem (per https://wiki.libsdl.org/SDL_PumpEvents ), so the whole idea of running your input loop on another thread to get

Sdl_pollevent Not Working

Figure1, "SDL initialization." shows the use of SDL_Init to initialize these subsystems. https://vilimpoc.org/research/portmonitorg/sdl-tips-and-tricks.html Hence esp. Sdl_waitevent Example Line 5 calls SDL_SetVideoMode to create an 800x600 window that can be used for OpenGL rendering. Sdl_pollevent Example During the development of the program I ran into issues where performance was bad due to tight looping in other threads; this not being the first time I had experienced this

Instead they just have to wait for the memory (graphics/sound) to be reloaded, without the gamestate changing. To avoid hogging the CPU (100% load) when the app isn't active, add something like: else // non-handled events SDL_Delay(100); here, or (better) do something that turns that SDL_PollEvent() at the Brainfuck Interpreter written in x86 Assembly Does Apex have an equivalent to the C# object initializer? Contents SDL_WaitEvent Syntax Function Parameters Return Value Code Examples Remarks Related Functions Syntax int SDL_WaitEvent(SDL_Event* event) Function Parameters event the SDL_Event structure to be filled in with the next event from Sdl_event

Content © SDL Wiki Navigation SDL Wiki Search Wiki Quick LinksFrontPageIntroductionSupportAPI By NameAPI By CategoryContributingRecentChangesFindPageWiki Help User ActionsLogin Wiki Page Content SDL_WaitEvent Use this function to wait indefinitely for the next I recommend to create limited layers. Reload to refresh your session. With event handling with SDL_PollEvent or SDL_WaitEvent, you get every mouse press and release.

For example, requesting 64 bits of red is sure to fail on any current generation system. Sdl Poll Events error path ... */ 3 4 atexit(SDL_Quit); The call to atexit adds the function SDL_Quit to the list of functions that are automatically called when the program terminates. Declare pointers to a mutex and a condition variable.

On most systems, the scheduler has a granularity of approximately 10 ms, so you're right; it's not always accurate enough.

The events are lost. Timing. This isn't really a restriction caused by SDL, it is a restriction caused by various operating systems. Sdl_pumpevents As this function implicitly calls SDL_PumpEvents(), you can only call this function in the thread that initialized the video subsystem.

Bye! I need to in Windows, or my other threads tend to starve. SDL_SysWMinfo Depending on whether you're using X11, Aqua, or Windows, there may be certain tricks you'd like to perform with your applications. I for one prefer games where pausing drastically reduces CPU usage.

SDL_Delay(1); ProcessEvents(); It all starts to work properly, ie: timer user events are processed immediately. Actions Ryan C. When this event is received, a flag is set that signals the event loop to terminate. Aug 3, 2010 at 8:22am UTC Zhuge (4642) Yes, though you should probably be handing the SDL_QUIT event in addition to any other events you want to handle.

A "black screen of death" game is limited to 50FPS or less. In many cases this is input from the user. Does any organism use both photosynthesis and respiration? int SDL_GL_SetAttribute(SDL_GLattr attr, int value); SDL_SetVideoMode creates the drawing surface[1].

Time measuring and waiting: For Windows: One can use QueryPerformanceCounter(), QueryPerformanceCounterFrequency(). You signed in with another tab or window. This is used, for example, to determine which key was pressed or released on the keyboard, the location of the mouse pointer, or the direction the joystick is being pushed. It will slow down your software for sure.

In some cases they actually know what they are doing. Figure3.Simple SDL event loop. 1 bool done = false; 2 3 while (!done) { 4 SDL_Event event; 5 6 SDL_WaitEvent(&event); 7 do { 8 switch (event.type) { 9 case SDL_QUIT: 10 miliseconds (or 8, 16, 24... However, if I replace this: SDL_WaitEvent( Null ); ProcessEvents();  //polls/pops events ...with this...

Problem #1: On a french keyboard (AFAIK), those two keys are swapped.

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