While i was searching the internet google often answered with linuxquestions.org. Now where i cant find an answer through google i thought i'll register myself in here. Because you guys helped me alot without knowing it Thank you so far!

Now, here i am!^^

I used to write some programs in ANSI C, OpenGL and xf86 (X11). Everything is working well. Now i want my programs to run under windows XP/Vista/7 too. As far as i read at LQ SDL is an API which provides me with a window and other stuff i need, like sound. My Questions are now:

Do i have lost in performance programming with sdl instead of glx and x11? How "much" do i lose?

Do i get more performance when i program seperate glx/x11 and gl/WinAPI? sure, i have to program each thing twice. like window initialization and keymapping.

ekual

before i forgot: i already searched the forum.

You know, you could simply compile and test the application instead of asking.

Anyway... unless your application should be able to render pictures at 5000 frames per second, I wouldn't worry much about performance - that, in my opinion, is a premature optimization.

The point of SDL (and other toolkits) is that you get one program version to babysit instead of several. I cannot give you glx vs SDL comparison, but SDL speed is comparable with what you can get by using WinAPI + OpenGL + DirectInput (for keyboard/mouse) on windows platform. Disable vsync, and achieving few hundreds frames per second won't be a problem. There may be few percents difference, though, but it'll be hard to notice.

In my opinion, you should not worry about performance (unless you have some really heavy graphic-related stuff) until you run into problem, and you should not worry about providing several platform-dependent versions to manage OpenGL, until you have to do that - that'll be premature optimization. Make your app, test it, and once it is working as expected, you can start finetuning. Even with SDL, you may run into some compiler-related cross-platform quirks (non standard functions like vsprintf can be implemented differently, non-standard sprintf parameters can behave differently, and so on), so you'll have things to do before optimizing.

Maybe i am just too much afraid. I like clean code and so i have a voice in my mind that everything i want to code must be written in plain c and OpenGL functions

I'll take a deeper look into SDL and just give it a try tho i have the feeling of losing the overview and i dont know what my code does exactly. Looks like i have to read the sdl header files.

thanks for your advice.