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Date: Sun, 22 Mar 2009 12:52:29 +0000 From: Luke Benstead Subject: OpenGL 3.0 Context Creation I've attached a patch which implements OpenGL 3.x context creation on the latest SVN. I've added two options to SDL_GL_SetAttribute, these are SDL_GL_CONTEXT_MAJOR_VERSION and SDL_GL_CONTEXT_MINOR_VERSION. These default to 2 and 1 respectively. If the major version is less than 3 then the current context creation method is used, otherwise the appropriate new context creation function is called (depending on the platform). Sample code: if (SDL_Init(SDL_INIT_VIDEO) != 0) { printf("Unable to initialize SDL: %s\n", SDL_GetError()); return 1; } SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3); //Without these 2 lines, SDL will create a GL 2.x context SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0); SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1); SDL_Surface* screen = SDL_SetVideoMode( 640, 480, 16, SDL_OPENGL | SDL_FULLSCREEN ); I've implemented context creation on both Win32 and X and run basic tests on both. This patch doesn't provide access to all the options allowed by the new context creation (e.g. shared contexts, forward compatible contexts) but they can be added pretty easily.
author Sam Lantinga <slouken@libsdl.org>
date Tue, 24 Mar 2009 10:43:53 +0000
parents 546f7c1eb755
children 1238da4a7112
line wrap: on
line source

.TH "SDL_SemWait" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_SemWait \- Lock a semaphore and suspend the thread if the semaphore value is zero\&.
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
#include "SDL_thread\&.h"
.sp
\fBint \fBSDL_SemWait\fP\fR(\fBSDL_sem *sem\fR);
.SH "DESCRIPTION"
.PP
\fBSDL_SemWait()\fP suspends the calling thread until either the semaphore pointed to by \fBsem\fR has a positive value, the call is interrupted by a signal or error\&. If the call is successful it will atomically decrement the semaphore value\&.
.PP
After \fBSDL_SemWait()\fP is successful, the semaphore can be released and its count atomically incremented by a successful call to \fISDL_SemPost\fR\&.
.SH "RETURN VALUE"
.PP
Returns \fB0\fR if successful or \fB-1\fR if there was an error (leaving the semaphore unchanged)\&.
.SH "EXAMPLES"
.PP
.PP
.nf
\f(CWif (SDL_SemWait(my_sem) == -1) {
        return WAIT_FAILED;
}

\&.\&.\&.

SDL_SemPost(my_sem);\fR
.fi
.PP
.SH "SEE ALSO"
.PP
\fI\fBSDL_CreateSemaphore\fP\fR, \fI\fBSDL_DestroySemaphore\fP\fR, \fI\fBSDL_SemTryWait\fP\fR, \fI\fBSDL_SemWaitTimeout\fP\fR, \fI\fBSDL_SemPost\fP\fR, \fI\fBSDL_SemValue\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00