view docs/man3/SDL_VideoModeOK.3 @ 4168:69bcba65c388 SDL-1.2

Fixed bug #526 Comment #1 From Simon Howard 2009-03-20 16:50:56 Hi, I'm the author of Chocolate Doom, one of the other source ports that James mentioned. This is a patch against the current SVN version of SDL 1.2 that fixes the bug. It has been tested and hopefully should be obviously correct from examining the changes. I'll give a brief explanation. When the palette is set with SDL_SetPalette, the IDirectDrawPalette_SetEntries DirectX function is invoked. However, when this happens, a WM_PALETTECHANGED message is sent to the window. A WM_PALETTECHANGED message can also be received if the palette is changed for some other reason, like if the system palette is changed. Therefore, the palette change handler (DX5_PaletteChanged) has code to deal with this case. It distinguishes "expected" palette changes (set with SDL_SetPalette) from "unexpected" palette changes using the colorchange_expected variable, which is set before calling IDirectDrawPalette_SetEntries. However, the code to set this variable is missing in the fullscreen code path. By setting this variable, the palette change is handled properly and the freezes go away.
author Sam Lantinga <slouken@libsdl.org>
date Mon, 13 Apr 2009 00:53:12 +0000
parents 4e3b250c950e
children 1238da4a7112
line wrap: on
line source

.TH "SDL_VideoModeOK" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_VideoModeOK \- Check to see if a particular video mode is supported\&.
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
.sp
\fBint \fBSDL_VideoModeOK\fP\fR(\fBint width, int height, int bpp, Uint32 flags\fR);
.SH "DESCRIPTION"
.PP
\fBSDL_VideoModeOK\fP returns \fB0\fR 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 \fIsurface\fR flags (see \fI\fBSDL_SetVideoMode\fP\fR)\&.
.PP
The bits-per-pixel value returned is only a suggested mode\&. You can usually request and bpp you want when \fIsetting\fR the video mode and SDL will emulate that color depth with a shadow video surface\&.
.PP
The arguments to \fBSDL_VideoModeOK\fP are the same ones you would pass to \fISDL_SetVideoMode\fR
.SH "EXAMPLE"
.PP
.nf
\f(CWSDL_Surface *screen;
Uint32 bpp;
\&.
\&.
\&.
printf("Checking mode 640x480@16bpp\&.
");
bpp=SDL_VideoModeOK(640, 480, 16, SDL_HWSURFACE);

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

printf("SDL Recommends 640x480@%dbpp\&.
", bpp);
screen=SDL_SetVideoMode(640, 480, bpp, SDL_HWSURFACE);
\&.
\&.\fR
.fi
.PP
.SH "SEE ALSO"
.PP
\fI\fBSDL_SetVideoMode\fP\fR, \fI\fBSDL_GetVideoInfo\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01