Possible screen resolutions in C/C++

yezu · 08-04-2009, 05:43 AM

Hi!
I am writing a game in OpenGL and I have encountered a problem.
I cannot find a way to get all possible screen resolutions.

SDL is not much of help unfortunately as SDL_ListModes tells me that "all resolutions are supported" which is pretty much useless :/

I have been looking for the xrandr code, and I found it a bit overwhelming :/

Can anyone help me find a solution, or at least provide some hints?

thanks

dmail · 08-04-2009, 06:40 AM

SDL_GetVideoInfo

Quote:

If it is called before SDL_SetVideoMode, the vfmt member of the returned structure will contain the pixel format of the best video mode.
... This read-only structure is returned by SDL_GetVideoInfo. It contains information on either the best available mode if called before SDL_SetVideoMode or the current video mode if called after SDL_SetVideoMode.

yezu · 08-04-2009, 07:09 AM

Thanks but SDL_GetVideoInfo is also useless as it only gives me the CURRENT resolution :/

dmail · 08-04-2009, 07:20 AM

Code:

std::list<LVD::Renderer::Resoultion> create_mode_list()
{
	SDL_PixelFormat format;
	SDL_Rect **modes;
	std::list<Resoultion_entry> mode_list;
	int loops(0);
	int bpp(0);
	do
	{
		//format.BitsPerPixel seems to get zeroed out on my windows box
		switch(loops)
		{
			case 0://32 bpp
				format.BitsPerPixel = 32;
				bpp = 32;
				break;
			case 1://24 bpp
				format.BitsPerPixel = 24;
				bpp = 24;
				break;
			case 2://16 bpp
				format.BitsPerPixel = 16;
				bpp = 16;
				break;
		}

		//get available fullscreen/hardware modes
		modes=SDL::SDL_ListModes(&format, SDL_FULLSCREEN);
		if(modes)
		{
			for(int i=0;modes[i];++i)
			{
				LVD::Renderer::Resoultion entry(modes[i]->w,modes[i]->h, bpp/*format.BitsPerPixel*/, 0);
				mode_list.push_back(entry);
			}
		}
	}while(++loops != 3);
	return mode_list;
}

knudfl · 08-04-2009, 07:54 AM

Do you mean
640x480, 800x600, 1024x768, 1152x864, 1280x768, 1280x960, 1280x1024
like the settings in 'gl-117' ?
http://www.heptargon.de/gl-117/gl-117.html
(( gl-117-1.3.2-src/src/conf.cpp ))
.....
Other OpenGL game with res. settings : Emilia Pinball
http://pinball.sourceforge.net/
.....