Mercurial > sdl-ios-xcode
view docs/man3/SDL_GL_GetProcAddress.3 @ 1555:780fd5b61df1
Fixed bug #89
Date: Sun, 23 Oct 2005 16:39:03 +0200
From: "A. Schmid" <sahib@phreaker.net>
Subject: [SDL] no software surfaces with svgalib driver?
Hi,
I noticed that the SDL (1.2.9) svgalib driver only makes use of linear
addressable (framebuffer) video modes. On older systems (like one of
mine), linear addressable modes are often not available.
Especially for cards with VESA VBE < 2.0 the svgalib vesa driver is
unusable, since VESA only supports framebuffering for VBE 2.0 and later.
The changes necessary to add support for software surfaces seem to be
relatively small. I only had to hack src/video/svga/SDL_svgavideo.c (see
attached patch). The code worked fine for me, but it is no more than a
proof of concept and should be reviewed (probably has a memory leak when
switching modes). It also uses the vgagl library (included in the
svgalib package) and needs to be linked against it.
-Alex
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sun, 19 Mar 2006 12:05:16 +0000 |
parents | e5bc29de3f0a |
children | 546f7c1eb755 |
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.TH "SDL_GL_GetProcAddress" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" .SH "NAME" SDL_GL_GetProcAddress\- Get the address of a GL function .SH "SYNOPSIS" .PP \fB#include "SDL\&.h" .sp \fBvoid *\fBSDL_GL_GetProcAddress\fP\fR(\fBconst char* proc\fR); .SH "DESCRIPTION" .PP Returns the address of the GL function \fBproc\fR, or \fBNULL\fR if the function is not found\&. If the GL library is loaded at runtime, with \fI\fBSDL_GL_LoadLibrary\fP\fR, then \fIall\fP GL functions must be retrieved this way\&. Usually this is used to retrieve function pointers to OpenGL extensions\&. .SH "EXAMPLE" .PP .nf \f(CWtypedef void (*GL_ActiveTextureARB_Func)(unsigned int); GL_ActiveTextureARB_Func glActiveTextureARB_ptr = 0; int has_multitexture=1; \&. \&. \&. /* Get function pointer */ glActiveTextureARB_ptr=(GL_ActiveTextureARB_Func) SDL_GL_GetProcAddress("glActiveTextureARB"); /* Check for a valid function ptr */ if(!glActiveTextureARB_ptr){ fprintf(stderr, "Multitexture Extensions not present\&. "); has_multitexture=0; } \&. \&. \&. \&. if(has_multitexture){ glActiveTextureARB_ptr(GL_TEXTURE0_ARB); \&. \&. } else{ \&. \&. }\fR .fi .PP .SH "SEE ALSO" .PP \fI\fBSDL_GL_LoadLibrary\fP\fR ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01