Acquire an OGL3.2 core profile when available

desmume/src/Makefile.am

@@ -173,7 +173,7 @@ libdesmume_a_SOURCES += \
 endif
 
 if HAVE_GL
-libdesmume_a_SOURCES += OGLRender.cpp
+libdesmume_a_SOURCES += OGLRender.cpp OGLRender_3_2.cpp
 endif
 
 if HAVE_OPENAL

desmume/src/OGLRender_3_2.h

@@ -39,8 +39,8 @@
 	#define EXTERNOGLEXT(procPtr, func)
 #else
 	#include <GL/gl.h>
-	#include <GL/glcorearb.h>
 	#include <GL/glx.h>
+	#include "utils/glcorearb.h"
 
 	#define OGLEXT(procPtr, func)		procPtr func = NULL;
 	#define INITOGLEXT(procPtr, func)	func = (procPtr)glXGetProcAddress((const GLubyte *) #func);

desmume/src/gtk/glx_3Demu.cpp

@@ -22,15 +22,19 @@
 #include <stdio.h>
 #include <X11/Xlib.h>
 #include <GL/glx.h>
+#include <GL/glxext.h>
 #include "../OGLRender.h"
 
 static bool glx_beginOpenGL(void) { return 1; }
 static void glx_endOpenGL(void) { }
 static bool glx_init(void) { return true; }
+static int xerror_handler(Display *dpy, XErrorEvent *ev) { return 0; }
 
 static GLXContext ctx;
 static GLXPbuffer pbuf;
 
+typedef GLXContext (*wtf)(Display*, GLXFBConfig, GLXContext, Bool, const int*);
+
 int deinit_glx_3Demu(void)
 {
     Display *dpy = glXGetCurrentDisplay();
@@ -111,10 +115,32 @@ int init_glx_3Demu(void)
     // The first should match exactly, otherwise is the least wrong one
     pbuf = glXCreatePbuffer(dpy, cfg[0], (int *)&pbuf_attr);
 
-    XFree(cfg);
+    // Dynamic linking is a pain, sigh
+    OGLEXT(PFNGLXCREATECONTEXTATTRIBSARBPROC, glXCreateContextAttribsARB);
+    INITOGLEXT(PFNGLXCREATECONTEXTATTRIBSARBPROC, glXCreateContextAttribsARB);
 
+    // Try to get a 3.2 core profile context
+    if (glXCreateContextAttribsARB) {
+        const int ctx_attr[] = {
+            GLX_CONTEXT_PROFILE_MASK_ARB, GLX_CONTEXT_CORE_PROFILE_BIT_ARB,
+            GLX_CONTEXT_MAJOR_VERSION_ARB, 3,
+            GLX_CONTEXT_MINOR_VERSION_ARB, 2,
+            None
+        };
+        // This silly dance is needed because if Xorg can't acquire the context
+        // we asked for it will throw an error, which is caught by GTK X error
+        // handler and made fatal. The show must go on.
+        int (*old_handler)(Display*, XErrorEvent*) = XSetErrorHandler(&xerror_handler);
+        ctx = glXCreateContextAttribsARB(dpy, cfg[0], 0, true, ctx_attr);
+        XSetErrorHandler(old_handler);
+    } 
+    
+    // Something went wrong, try with a standard context
+    if (!ctx)
         ctx = glXCreateContext(dpy, vis, NULL, true);
 
+    XFree(cfg);
+
     if (!ctx)
       return false;
 

desmume/src/gtk/main.cpp

@@ -70,6 +70,7 @@
 #include <GL/gl.h>
 #include <GL/glu.h>
 #include "OGLRender.h"
+#include "OGLRender_3_2.h"
 #include "osmesa_3Demu.h"
 #include "glx_3Demu.h"
 #endif
@@ -593,10 +594,9 @@ NULL
 
 GPU3DInterface *core3DList[] = {
   &gpu3DNull,
-  &gpu3DRasterize
+  &gpu3DRasterize,
 #if defined(HAVE_LIBOSMESA) || defined(HAVE_GL_GLX)
-  ,
-  &gpu3Dgl
+  &gpu3Dgl,
 #endif
 };
 
@@ -3195,6 +3195,9 @@ common_gtk_main( class configured_features *my_config)
             gtk_toggle_action_set_active((GtkToggleAction *)action, FALSE);
     }
 
+    OGLLoadEntryPoints_3_2_Func = OGLLoadEntryPoints_3_2;
+    OGLCreateRenderer_3_2_Func = OGLCreateRenderer_3_2;
+
     //Set the 3D emulation to use
     unsigned core = my_config->engine_3d;
     // setup the gdk 3D emulation;