# HG changeset patch
# User Sam Lantinga <slouken@libsdl.org>
# Date 1238779145 0
# Node ID cdeee9f9b14ba43c8ad83dd5bbd17d72d947dd01
# Parent  86ea6c073d87d9928f95bdc08a87d0f1c51df6b5
Fixed bug #721

From  michalziulek@gmail.com   2009-03-28 07:43:34   (-) [reply]

There is a bug in OpenGL 3.x context creation code.
Function glXGetProcAddress is used directly where it should be:
_this->gl_data->glXGetProcAddress. I have attached patch which fixes this on
x11 and win32. Thanks.

diff -r 86ea6c073d87 -r cdeee9f9b14b src/video/win32/SDL_win32opengl.c
--- a/src/video/win32/SDL_win32opengl.c	Fri Apr 03 13:35:05 2009 +0000
+++ b/src/video/win32/SDL_win32opengl.c	Fri Apr 03 17:19:05 2009 +0000
@@ -512,7 +512,7 @@
             return NULL;
         }
                 
-        wglCreateContextAttribsARB = (PFNWGLCREATECONTEXTATTRIBSARBPROC) wglGetProcAddress("wglCreateContextAttribsARB");
+        wglCreateContextAttribsARB = (PFNWGLCREATECONTEXTATTRIBSARBPROC) _this->gl_data->wglGetProcAddress("wglCreateContextAttribsARB");
         if (!wglCreateContextAttribsARB) {
             SDL_SetError("GL 3.x is not supported");
             context = temp_context;
@@ -525,7 +525,7 @@
             /* Create the GL 3.x context */
             context = wglCreateContextAttribsARB(hdc, 0, attribs);
             /* Delete the GL 2.x context */
-            wglDeleteContext(temp_context);
+            _this->gl_data->wglDeleteContext(temp_context);
         }
     }
     
diff -r 86ea6c073d87 -r cdeee9f9b14b src/video/x11/SDL_x11opengl.c
--- a/src/video/x11/SDL_x11opengl.c	Fri Apr 03 13:35:05 2009 +0000
+++ b/src/video/x11/SDL_x11opengl.c	Fri Apr 03 17:19:05 2009 +0000
@@ -413,21 +413,24 @@
                 };
                                 
                 /* Get a pointer to the context creation function for GL 3.0 */
-                PFNGLXCREATECONTEXTATTRIBSARBPROC glXCreateContextAttribs = (PFNGLXCREATECONTEXTATTRIBSARBPROC)glXGetProcAddress((GLubyte*)"glXCreateContextAttribsARB");
+                PFNGLXCREATECONTEXTATTRIBSARBPROC glXCreateContextAttribs = (PFNGLXCREATECONTEXTATTRIBSARBPROC)_this->gl_data->glXGetProcAddress((GLubyte*)"glXCreateContextAttribsARB");
                 if (!glXCreateContextAttribs) {
                     SDL_SetError("GL 3.x is not supported");
                     context = temp_context;
                 } else {
-                    /* Create a GL 3.0 context */
+                    /* Create a GL 3.x context */
                     GLXFBConfig *framebuffer_config = NULL;
                     int fbcount = 0;                
-                    framebuffer_config = glXChooseFBConfig(display, DefaultScreen(display), NULL, &fbcount);
-                    if (!framebuffer_config) {
-                        SDL_SetError("No good framebuffers found. GL 3.0 disabled");
+                    GLXFBConfig* (*glXChooseFBConfig)(Display* disp, int screen, const int* attrib_list, int* nelements);
+
+                    glXChooseFBConfig = (GLXFBConfig* (*)(Display*, int, const int*, int*))_this->gl_data->glXGetProcAddress((GLubyte*)"glXChooseFBConfig");
+
+                    if (!glXChooseFBConfig || !(framebuffer_config = glXChooseFBConfig(display, DefaultScreen(display), NULL, &fbcount))) {
+                        SDL_SetError("No good framebuffers found. GL 3.x disabled");
                         context = temp_context;
                     } else {                                    
                         context = glXCreateContextAttribs(display, framebuffer_config[0], NULL, True, attribs);
-                        glXDestroyContext(display, temp_context);
+                        _this->gl_data->glXDestroyContext(display, temp_context);
                     }
                 }
             }