view docs/man3/SDL_SetColorKey.3 @ 638:b0108e9dea53

Date: Sun, 11 May 2003 19:59:06 +0300 From: Pasi K?rkk?inen Subject: [PATCH] fix SDL OpenGL segfault with DRI/Mesa drivers and Glew Hello! The attached patch fixes a bug in SDL which causes SDL to crash in X11_GL_Shutdown() if you are using DRI/Mesa drivers AND glew (http://glew.sf.net). The bug is caused by a namespace collision affecting dlsym() to fetch wrong pointer for glXReleaseBuffersMESA() (uninitialized pointer from glew because the extension is NOT supported by the driver) and then SDL calling it in X11_GL_Shutdown(). SDL should check if the glXReleaseBuffersMESA() is really supported by the driver (from the extensions string) before calling it. Attached patch adds extension string parsing to check if glXReleaseBuffersMESA() is really supported (and this way prevents the segfault). Availability of the extensions should be _always_ checked from the extensions string rather than using dlsym()! Please add it to the next version of SDL. Thanks to gltron and author of glew to help fixing this.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 28 Jun 2003 17:27:33 +0000
parents e5bc29de3f0a
children 546f7c1eb755
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line source

.TH "SDL_SetColorKey" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_SetColorKey\- Sets the color key (transparent pixel) in a blittable surface and RLE acceleration\&.
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
.sp
\fBint \fBSDL_SetColorKey\fP\fR(\fBSDL_Surface *surface, Uint32 flag, Uint32 key\fR);
.SH "DESCRIPTION"
.PP
 Sets the color key (transparent pixel) in a blittable surface and enables or disables RLE blit acceleration\&.
.PP
RLE acceleration can substantially speed up blitting of images with large horizontal runs of transparent pixels (i\&.e\&., pixels that match the \fBkey\fR value)\&. The \fBkey\fR must be of the same pixel format as the \fBsurface\fR, \fI\fBSDL_MapRGB\fP\fR is often useful for obtaining an acceptable value\&.
.PP
If \fBflag\fR is \fBSDL_SRCCOLORKEY\fP then \fBkey\fR is the transparent pixel value in the source image of a blit\&.
.PP
If \fBflag\fR is OR\&'d with \fBSDL_RLEACCEL\fP then the surface will be draw using RLE acceleration when drawn with \fISDL_BlitSurface\fR\&. The surface will actually be encoded for RLE acceleration the first time \fISDL_BlitSurface\fR or \fISDL_DisplayFormat\fR is called on the surface\&.
.PP
If \fBflag\fR is 0, this function clears any current color key\&.
.SH "RETURN VALUE"
.PP
This function returns \fB0\fR, or \fB-1\fR if there was an error\&.
.SH "SEE ALSO"
.PP
\fI\fBSDL_BlitSurface\fP\fR, \fI\fBSDL_DisplayFormat\fP\fR, \fI\fBSDL_MapRGB\fP\fR, \fI\fBSDL_SetAlpha\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01