Mercurial > sdl-ios-xcode
view docs/man3/SDL_LockSurface.3 @ 1120:8e1fde455471
Patch by me to fix crash described below.
--ryan.
To: sdl@libsdl.org
From: Rainer Deyke <rainerd@eldwood.com>
Date: Tue, 16 Aug 2005 01:08:18 -0600
Subject: [SDL] Bug report: SDL_CreateRGBSurface with SDL_HWSURFACE crashes
If SDL is in full-screen mode with a hardware video surface on OS X,
SDL_CreateRGBSurface with SDL_HWSURFACE crashes. The crash occurs on
line 109 of SDL_Surface.c. This was tested on OS X 10.3.9 with both SDL
1.2.8 and the latest CVS. Here is a small C++ program that demonstrates
the problem:
#include "SDL.h"
#include <stdio.h>
namespace {
void wait_for_key()
{
SDL_Event e;
printf("%d\n", SDL_GetAppState());
while (SDL_WaitEvent(&e)) {
if (e.type == SDL_KEYDOWN || e.type == SDL_QUIT) return;
}
}
}
int main(int, char *[])
{
SDL_Init(SDL_INIT_VIDEO);
SDL_Surface *screen
= SDL_SetVideoMode(640, 480, 32, SDL_FULLSCREEN | SDL_HWSURFACE);
SDL_Surface *s = SDL_CreateRGBSurface(SDL_HWSURFACE, 640, 480, 32,
screen->format->Rmask, screen->format->Gmask,
screen->format->Bmask, screen->format->Amask);
wait_for_key();
if (s) SDL_FreeSurface(s);
SDL_Quit();
printf("Success!\n");
return 0;
}
| author | Ryan C. Gordon <icculus@icculus.org> |
|---|---|
| date | Thu, 18 Aug 2005 06:46:32 +0000 |
| parents | e5bc29de3f0a |
| children | 546f7c1eb755 |
line wrap: on
line source
.TH "SDL_LockSurface" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" .SH "NAME" SDL_LockSurface\- Lock a surface for directly access\&. .SH "SYNOPSIS" .PP \fB#include "SDL\&.h" .sp \fBint \fBSDL_LockSurface\fP\fR(\fBSDL_Surface *surface\fR); .SH "DESCRIPTION" .PP \fBSDL_LockSurface\fP sets up a surface for directly accessing the pixels\&. Between calls to \fBSDL_LockSurface\fP and \fBSDL_UnlockSurface\fP, you can write to and read from \fBsurface->\fBpixels\fR\fR, using the pixel format stored in \fBsurface->\fBformat\fR\fR\&. Once you are done accessing the surface, you should use \fBSDL_UnlockSurface\fP to release it\&. .PP Not all surfaces require locking\&. If \fBSDL_MUSTLOCK\fP(\fBsurface\fR) evaluates to \fB0\fR, then you can read and write to the surface at any time, and the pixel format of the surface will not change\&. .PP No operating system or library calls should be made between lock/unlock pairs, as critical system locks may be held during this time\&. .PP It should be noted, that since SDL 1\&.1\&.8 surface locks are recursive\&. This means that you can lock a surface multiple times, but each lock must have a match unlock\&. .PP .nf \f(CW \&. \&. SDL_LockSurface( surface ); \&. /* Surface is locked */ /* Direct pixel access on surface here */ \&. SDL_LockSurface( surface ); \&. /* More direct pixel access on surface */ \&. SDL_UnlockSurface( surface ); /* Surface is still locked */ /* Note: Is versions < 1\&.1\&.8, the surface would have been */ /* no longer locked at this stage */ \&. SDL_UnlockSurface( surface ); /* Surface is now unlocked */ \&. \&.\fR .fi .PP .SH "RETURN VALUE" .PP \fBSDL_LockSurface\fP returns \fB0\fR, or \fB-1\fR if the surface couldn\&'t be locked\&. .SH "SEE ALSO" .PP \fI\fBSDL_UnlockSurface\fP\fR ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01