view docs/html/sdlvideomodeok.html @ 1257:448a9a64537b

[PATCH] SDL_GetVideoMode() does not find best mode, part 2 Following commit 1.51, I come accross a problem when SDL must choose between several video modes that could suit the one asked. If I ask 320x240 with this list: 768x480 768x240 640x400 640x200 384x480 384x240 320x400 320x200 The smallest selectables modes are 384x240 and 320x400. And SDL choose the later in this list, but 384x240 is more suitable. So I added a check to compare the pixel count (surface) of modes, and select the one which has the smallest pixel count. In my example, 384x240 has 92160 pixels, and 320x400 has 128000 pixels. So now SDL will choose 384x240 for the asked 320x240 mode.
author Patrice Mandin <patmandin@gmail.com>
date Thu, 19 Jan 2006 21:28:52 +0000
parents 355632dca928
children
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>SDL_VideoModeOK</H1
><DIV
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><A
NAME="AEN1202"
></A
><H2
>Name</H2
>SDL_VideoModeOK&nbsp;--&nbsp;Check to see if a particular video mode is supported.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
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>Synopsis</H2
><DIV
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><P
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_VideoModeOK</B
></CODE
>(int width, int height, int bpp, Uint32 flags);</CODE
></P
><P
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><DIV
CLASS="REFSECT1"
><A
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></A
><H2
>Description</H2
><P
><TT
CLASS="FUNCTION"
>SDL_VideoModeOK</TT
> returns <SPAN
CLASS="RETURNVALUE"
>0</SPAN
> 
if the requested mode is not supported under any bit depth, or returns the 
bits-per-pixel of the closest available mode with the given width, height and requested <A
HREF="sdlsurface.html"
>surface</A
> flags (see <A
HREF="sdlsetvideomode.html"
><TT
CLASS="FUNCTION"
>SDL_SetVideoMode</TT
></A
>).</P
><P
>The bits-per-pixel value returned is only a suggested mode. You can usually request and bpp you want when <A
HREF="sdlsetvideomode.html"
>setting</A
>  the video mode and SDL will emulate that color depth with a shadow video surface.</P
><P
>The arguments to <TT
CLASS="FUNCTION"
>SDL_VideoModeOK</TT
> are the same ones you 
would pass to <A
HREF="sdlsetvideomode.html"
>SDL_SetVideoMode</A
></P
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><H2
>Example</H2
><PRE
CLASS="PROGRAMLISTING"
>SDL_Surface *screen;
Uint32 bpp;
.
.
.
printf("Checking mode 640x480@16bpp.\n");
bpp=SDL_VideoModeOK(640, 480, 16, SDL_HWSURFACE);

if(!bpp){
  printf("Mode not available.\n");
  exit(-1);
}

printf("SDL Recommends 640x480@%dbpp.\n", bpp);
screen=SDL_SetVideoMode(640, 480, bpp, SDL_HWSURFACE);
.
.</PRE
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>See Also</H2
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><A
HREF="sdlsetvideomode.html"
><TT
CLASS="FUNCTION"
>SDL_SetVideoMode</TT
></A
>,
<A
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><TT
CLASS="FUNCTION"
>SDL_GetVideoInfo</TT
></A
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