gtkglarea r99 - trunk/gtkgl

[samh svn gnome org]

Author: samh
Date: Fri Mar  7 12:45:30 2008
New Revision: 99
URL: http://svn.gnome.org/viewvc/gtkglarea?rev=99&view=rev

Log:
  * Starting the gtkgl.c reorganisation.


Modified:
   trunk/gtkgl/gdkgl.c

Modified: trunk/gtkgl/gdkgl.c
==============================================================================
--- trunk/gtkgl/gdkgl.c	(original)
+++ trunk/gtkgl/gdkgl.c	Fri Mar  7 12:45:30 2008
@@ -31,118 +31,71 @@
 
 #include "gdkgl.h"
 
+/*
+ *  The GdkGLContext class
+ */
+struct _GdkGLContext {
+  GObject     parent;
 #ifdef USE_WIN32
-static void fill_pfd(PIXELFORMATDESCRIPTOR *pfd, int *attriblist)
-{
-  /*
-   * Ripped from glut's win32_x11.c
-   */
-
-  int *p = attriblist;
-
-  memset(pfd, 0, sizeof(PIXELFORMATDESCRIPTOR));
-  pfd->nSize = (sizeof(PIXELFORMATDESCRIPTOR));
-  pfd->nVersion = 1;
+  gboolean  initialised;
+  HGLRC     hglrc;
+  HDC       hdc;
+  HWND      hwnd;
+  GdkGLContext *share;
+  PIXELFORMATDESCRIPTOR pfd;
+#else
+  Display    *xdisplay;
+  GLXContext  glxcontext;
+#endif
+};
 
-  /* Defaults. */
-  pfd->dwFlags = PFD_SUPPORT_OPENGL | PFD_DRAW_TO_WINDOW;
-  pfd->iPixelType = PFD_TYPE_COLORINDEX;
-  pfd->cColorBits = 32;
-  pfd->cDepthBits = 0;
-  pfd->cAccumBits = 0;
+struct _GdkGLContextClass {
+  GObjectClass parent_class;
+};
+typedef struct _GdkGLContextClass GdkGLContextClass;
 
-  while (*p) {
-    switch (*p) {
-    case GDK_GL_USE_GL:
-      pfd->dwFlags |= PFD_SUPPORT_OPENGL;
-      break;
-    case GDK_GL_BUFFER_SIZE:
-      pfd->cColorBits = *(++p);
-      break;
-    case GDK_GL_LEVEL:
-      /* the bReserved flag of the pfd contains the
-         overlay/underlay info. */
-      pfd->bReserved = *(++p);
-      break;
-    case GDK_GL_RGBA:
-      pfd->iPixelType = PFD_TYPE_RGBA;
-      break;
-    case GDK_GL_DOUBLEBUFFER:
-      pfd->dwFlags |= PFD_DOUBLEBUFFER;
-      break;
-    case GDK_GL_STEREO:
-      pfd->dwFlags |= PFD_STEREO;
-      break;
-    case GDK_GL_AUX_BUFFERS:
-      pfd->cAuxBuffers = *(++p);
-      break;
-    case GDK_GL_RED_SIZE:
-      pfd->cRedBits = 8; /* Try to get the maximum. */
-      ++p;
-      break;
-    case GDK_GL_GREEN_SIZE:
-      pfd->cGreenBits = 8;
-      ++p;
-      break;
-    case GDK_GL_BLUE_SIZE:
-      pfd->cBlueBits = 8;
-      ++p;
-      break;
-    case GDK_GL_ALPHA_SIZE:
-      pfd->cAlphaBits = 8;
-      ++p;
-      break;
-    case GDK_GL_DEPTH_SIZE:
-      pfd->cDepthBits = 32;
-      ++p;
-      break;
-    case GDK_GL_STENCIL_SIZE:
-      pfd->cStencilBits = *(++p);
-      break;
-    case GDK_GL_ACCUM_RED_SIZE:
-    case GDK_GL_ACCUM_GREEN_SIZE:
-    case GDK_GL_ACCUM_BLUE_SIZE:
-    case GDK_GL_ACCUM_ALPHA_SIZE:
-      /* I believe that WGL only used the cAccumRedBits,
-         cAccumBlueBits, cAccumGreenBits, and cAccumAlphaBits fields
-         when returning info about the accumulation buffer precision.
-         Only cAccumBits is used for requesting an accumulation
-         buffer. */
-      pfd->cAccumBits += *(++p);
-                break;
-    }
-    ++p;
-  }
-}
+static GObjectClass *glcontext_parent_class;
+static void gdk_gl_context_class_init (GdkGLContextClass *class);
 
+/*
+ *  The GdkGLPixmap class
+ */
+struct _GdkGLPixmap {
+  GObject   parent;
+#ifdef USE_WIN32
+  gboolean  initialised;
+  HDC       hdc;
+  HBITMAP   hbitmap;
+  GdkPixmap *pixmap;
 #else
-static XVisualInfo *get_xvisualinfo(GdkVisual *visual)
-{
-  Display *dpy;
-  XVisualInfo vinfo_template;
-  XVisualInfo *vi;
-  int nitems_return;
-
-  dpy = GDK_DISPLAY();
+  Display   *xdisplay;
+  GLXPixmap glxpixmap;
+  GdkPixmap *front_left;
+#endif
+};
 
-  /* 'GLX uses VisualInfo records because they uniquely identify
-   * a (VisualID,screen,depth) tuple.'
-   */
-  vinfo_template.visual   = GDK_VISUAL_XVISUAL(visual);
-  vinfo_template.visualid = XVisualIDFromVisual(vinfo_template.visual);
-  vinfo_template.depth    = visual->depth;
-  vinfo_template.screen   = DefaultScreen(dpy);
-  vi = XGetVisualInfo(dpy, VisualIDMask|VisualDepthMask|VisualScreenMask,
-		      &vinfo_template, &nitems_return);
+struct _GdkGLPixmapClass {
+  GObjectClass parent_class;
+};
+typedef struct _GdkGLPixmapClass GdkGLPixmapClass;
 
-  g_assert( vi!=0  && nitems_return==1 ); /* visualinfo needs to be unique */
+static GObjectClass *glpixmap_parent_class;
+static void gdk_gl_pixmap_class_init (GdkGLPixmapClass *class);
 
-  /* remember to XFree returned XVisualInfo !!! */
-  return vi;
-}
+/*
+ *  Local helper functions
+ */
+#ifdef USE_WIN32
+static void fill_pfd(PIXELFORMATDESCRIPTOR *pfd, int *attriblist);
+#else
+static XVisualInfo *get_xvisualinfo(GdkVisual *visual);
 #endif
 
 
+/*
+ *  Generic GL support
+ */
+
 gint gdk_gl_query(void)
 {
 #ifdef USE_WIN32
@@ -155,21 +108,20 @@
 
 gchar *gdk_gl_get_info()
 {
+  char const *vendor, *version, *extensions;
 #ifdef USE_WIN32
+  vendor = glGetString (GL_VENDOR);
+  version = glGetString (GL_VERSION);
+  extensions = glGetString (GL_EXTENSIONS);
+#else
+  vendor = glXGetClientString(GDK_DISPLAY(), GLX_VENDOR);
+  version = glXGetClientString(GDK_DISPLAY(), GLX_VERSION);
+  extensions = glXGetClientString(GDK_DISPLAY(), GLX_EXTENSIONS);
+#endif
   return g_strdup_printf("VENDOR     : %s\n"
                          "VERSION    : %s\n"
                          "EXTENSIONS : %s\n",
-                         glGetString ( GL_VENDOR ),
-                         glGetString ( GL_VERSION ),
-                         glGetString ( GL_EXTENSIONS ));
-#else
-  return g_strdup_printf("VENDOR     : %s\n"
-			 "VERSION    : %s\n"
-			 "EXTENSIONS : %s\n",
-			 glXGetClientString(GDK_DISPLAY(), GLX_VENDOR),
-			 glXGetClientString(GDK_DISPLAY(), GLX_VERSION),
-			 glXGetClientString(GDK_DISPLAY(), GLX_EXTENSIONS));
-#endif
+                         vendor, version, extensions);
 }
 
 
@@ -180,14 +132,15 @@
 #else
   Display *dpy;
   XVisualInfo *vi;
-  GdkVisual  *visual;
+  GdkVisual *visual;
 
   g_return_val_if_fail(attrlist != NULL, NULL);
 
   dpy = GDK_DISPLAY();
-  if ((vi = glXChooseVisual(dpy,DefaultScreen(dpy), attrlist)) == NULL)
+  vi = glXChooseVisual(dpy, DefaultScreen(dpy), attrlist);
+  if (!vi)
     return NULL;
-  
+
   visual = gdkx_visual_get(vi->visualid);
   XFree(vi);
   return visual;
@@ -198,7 +151,7 @@
 int gdk_gl_get_config(GdkVisual *visual, int attrib)
 {
 #ifdef USE_WIN32
-  g_warning ( "not implemented" );
+  g_warning ("not implemented");
   return 0;
 #else
   Display *dpy;
@@ -221,28 +174,10 @@
 #endif
 }
 
-struct _GdkGLContext {
-  GObject     parent;
-#ifdef USE_WIN32
-  gboolean  initialised;
-  HGLRC     hglrc;
-  HDC       hdc;
-  HWND      hwnd;
-  GdkGLContext *share;
-  PIXELFORMATDESCRIPTOR pfd;
-#else
-  Display    *xdisplay;
-  GLXContext  glxcontext;
-#endif
-};
-struct _GdkGLContextClass {
-  GObjectClass parent_class;
-};
-typedef struct _GdkGLContextClass GdkGLContextClass;
 
-static GObjectClass *glcontext_parent_class;
-
-static void gdk_gl_context_class_init (GdkGLContextClass *class);
+/*
+ *  GL context support
+ */
 
 GType
 gdk_gl_context_get_type (void)
@@ -279,15 +214,15 @@
   context = GDK_GL_CONTEXT(object);
 
 #ifdef USE_WIN32
-  if (context->hglrc == wglGetCurrentContext () )
-    wglMakeCurrent ( NULL, NULL );
+  if (context->hglrc == wglGetCurrentContext ())
+    wglMakeCurrent (NULL, NULL);
 
-  wglDeleteContext ( context->hglrc );
+  wglDeleteContext (context->hglrc);
 
-  if ( context->hwnd )
-    ReleaseDC ( context->hwnd, context->hdc );
+  if (context->hwnd)
+    ReleaseDC (context->hwnd, context->hdc);
   else
-    DeleteDC ( context->hdc );
+    DeleteDC (context->hdc);
 #else
   if (context->glxcontext) {
     if (context->glxcontext == glXGetCurrentContext())
@@ -301,6 +236,7 @@
   (* glcontext_parent_class->finalize)(object);
 }
 
+
 static void
 gdk_gl_context_class_init(GdkGLContextClass *class)
 {
@@ -312,6 +248,7 @@
   gobject_class->finalize = gdk_gl_context_finalize;
 }
 
+
 GdkGLContext *
 gdk_gl_context_new(GdkVisual *visual)
 {
@@ -324,55 +261,41 @@
 {
 #ifdef USE_WIN32
   GdkGLContext *context;
+#else
+  Display *dpy;
+  XVisualInfo *vi;
+  GLXContext glxcontext;
+  GdkGLContext *context;
+#endif
 
-  g_return_val_if_fail ( visual != NULL, NULL );
+  g_return_val_if_fail (visual != NULL, NULL);
 
   context = g_object_new(GDK_TYPE_GL_CONTEXT, NULL);
-  if (!context) return NULL;
+  if (!context)
+    return NULL;
 
+#ifdef USE_WIN32
   context->initialised = FALSE;
   context->hglrc   = NULL;
   context->hdc     = NULL;
   context->hwnd    = NULL;
   context->share   = sharelist ? g_object_ref(sharelist) : NULL;
 
-  memset ( &(context->pfd), 0, sizeof(PIXELFORMATDESCRIPTOR) );
+  memset (&(context->pfd), 0, sizeof(PIXELFORMATDESCRIPTOR));
 
-  /* if direct is TRUE, we create a context which renders to the screen, otherwise
-     we create one to render to an offscreen bitmap */
-  if ( direct )
-  {
-    context->pfd.nSize = sizeof(PIXELFORMATDESCRIPTOR);
-    context->pfd.nVersion = 1;
+  /* if direct is TRUE, we create a context which renders to the screen,
+     otherwise we create one to render to an offscreen bitmap */
+  context->pfd.nSize = sizeof(PIXELFORMATDESCRIPTOR);
+  context->pfd.nVersion = 1;
+  if (direct)
     context->pfd.dwFlags = PFD_SUPPORT_OPENGL | PFD_DRAW_TO_WINDOW | PFD_DOUBLEBUFFER;
-    context->pfd.iPixelType = PFD_TYPE_RGBA;
-    context->pfd.cColorBits = 24;
-    context->pfd.cDepthBits = 32;
-    context->pfd.iLayerType = PFD_MAIN_PLANE;
-  }
   else
-  {
-    context->pfd.nSize = sizeof(PIXELFORMATDESCRIPTOR);
-    context->pfd.nVersion = 1;
     context->pfd.dwFlags = PFD_SUPPORT_OPENGL | PFD_DRAW_TO_BITMAP | PFD_SUPPORT_GDI;
-    context->pfd.iPixelType = PFD_TYPE_RGBA;
-    context->pfd.cColorBits = 24;
-    context->pfd.cDepthBits = 32;
-    context->pfd.iLayerType = PFD_MAIN_PLANE;
-  }
- 
-  return context;
+  context->pfd.iPixelType = PFD_TYPE_RGBA;
+  context->pfd.cColorBits = 24;
+  context->pfd.cDepthBits = 32;
+  context->pfd.iLayerType = PFD_MAIN_PLANE;
 #else
-  Display *dpy;
-  XVisualInfo *vi;
-  GLXContext glxcontext;
-  GdkGLContext *context;
-
-  g_return_val_if_fail(visual != NULL, NULL);
-
-  context = g_object_new(GDK_TYPE_GL_CONTEXT, NULL);
-  if (!context) return NULL;
-
   dpy = GDK_DISPLAY();
 
   vi = get_xvisualinfo(visual);
@@ -390,20 +313,25 @@
   
   context->xdisplay = dpy;
   context->glxcontext = glxcontext;
+#endif
   
   return context;
-#endif
 }
 
 GdkGLContext *gdk_gl_context_attrlist_share_new(int *attrlist, GdkGLContext *sharelist, gint direct)
 {
 #ifdef USE_WIN32
   GdkGLContext *context;
+#else
+  GdkVisual *visual;
+#endif
 
   g_return_val_if_fail(attrlist != NULL, NULL);
 
+#ifdef USE_WIN32
   context = g_object_new(GDK_TYPE_GL_CONTEXT, NULL);
-  if (!context) return NULL;
+  if (!context)
+    return NULL;
 
   context->initialised = FALSE;
   context->hglrc    = NULL;
@@ -414,55 +342,53 @@
 
   return context;
 #else
-  GdkVisual *visual = gdk_gl_choose_visual(attrlist);
-  if (visual)
-    return gdk_gl_context_share_new(visual, sharelist, direct);
-  return NULL;
+  visual = gdk_gl_choose_visual(attrlist);
+  if (!visual)
+    return NULL;
+
+  return gdk_gl_context_share_new(visual, sharelist, direct);
 #endif
 }
 
 
 gint gdk_gl_make_current(GdkDrawable *drawable, GdkGLContext *context)
 {
-#ifdef USE_WIN32
-  g_return_val_if_fail (GDK_IS_DRAWABLE(drawable), FALSE );
-  g_return_val_if_fail (GDK_IS_GL_CONTEXT(context), FALSE );
+  g_return_val_if_fail (GDK_IS_DRAWABLE(drawable), FALSE);
+  g_return_val_if_fail (GDK_IS_GL_CONTEXT(context), FALSE);
 
-  if ( !context->initialised )
+#ifdef USE_WIN32
+  if (!context->initialised)
   {
     int pf;
-    HWND hwnd = (HWND) gdk_win32_drawable_get_handle ( drawable );
+    HWND hwnd = (HWND) gdk_win32_drawable_get_handle (drawable);
 
-    context->hdc = GetDC ( hwnd );
+    context->hdc = GetDC (hwnd);
 
-    pf = ChoosePixelFormat ( context->hdc, &context->pfd );
+    pf = ChoosePixelFormat (context->hdc, &context->pfd);
 
-    if ( pf != 0 )
+    if (pf != 0)
         {
-          SetPixelFormat ( context->hdc, pf, &context->pfd );
-          context->hglrc = wglCreateContext ( context->hdc );
+          SetPixelFormat (context->hdc, pf, &context->pfd);
+          context->hglrc = wglCreateContext (context->hdc);
         }
 
     if (context->share)
         {
-          if ( context->share->hglrc )
-            wglShareLists ( context->share->hglrc, context->hglrc );
-          g_object_unref ( context->share );
+          if (context->share->hglrc)
+            wglShareLists (context->share->hglrc, context->hglrc);
+          g_object_unref (context->share);
         }
 
     context->initialised = TRUE;
   }
 
-  g_return_val_if_fail ( context->hdc    != NULL, FALSE );
-  g_return_val_if_fail ( context->hglrc  != NULL, FALSE );
+  g_return_val_if_fail (context->hdc    != NULL, FALSE);
+  g_return_val_if_fail (context->hglrc  != NULL, FALSE);
 
-  wglMakeCurrent ( context->hdc, context->hglrc );
+  wglMakeCurrent (context->hdc, context->hglrc);
 
   return TRUE;
 #else
-  g_return_val_if_fail(drawable != NULL, FALSE);
-  g_return_val_if_fail(context  != NULL, FALSE);
-
   return (glXMakeCurrent(context->xdisplay, GDK_WINDOW_XWINDOW(drawable),
 			 context->glxcontext) == True) ? TRUE : FALSE;
 
@@ -485,21 +411,21 @@
 #ifdef USE_WIN32
   HDC   hdc;
   HWND  hwnd;
+#endif
 
-  g_return_if_fail ( GDK_IS_DRAWABLE(drawable) );
+  g_return_if_fail (GDK_IS_DRAWABLE(drawable));
 
-  hwnd = (HWND) gdk_win32_drawable_get_handle ( drawable );
-  hdc  = GetDC ( hwnd );
-  if ( hdc  == NULL )
+#ifdef USE_WIN32
+  hwnd = (HWND) gdk_win32_drawable_get_handle (drawable);
+  hdc  = GetDC (hwnd);
+  if (hdc  == NULL)
   {
-     g_warning ( "gdk_gl_swap_buffers: GetDC failed" );
+     g_warning ("gdk_gl_swap_buffers: GetDC failed");
      return;
   }
-  SwapBuffers ( hdc );
-  ReleaseDC ( hwnd, hdc );
+  SwapBuffers (hdc);
+  ReleaseDC (hwnd, hdc);
 #else
-  g_return_if_fail(drawable != NULL);
-
   glXSwapBuffers(GDK_WINDOW_XDISPLAY(drawable), GDK_WINDOW_XWINDOW(drawable));
 #endif
 }
@@ -507,7 +433,7 @@
 void gdk_gl_wait_gdk(void)
 {
 #ifdef USE_WIN32
-  GdiFlush ();
+  GdiFlush();
 #else
   glXWaitX();
 #endif
@@ -516,38 +442,16 @@
 void gdk_gl_wait_gl (void)
 {
 #ifdef USE_WIN32
-  glFinish ();
+  glFinish();
 #else
   glXWaitGL();
 #endif
 }
 
 
-/* glpixmap stuff */
-
-struct _GdkGLPixmap {
-#ifdef USE_WIN32
-  GObject   object;
-  gboolean  initialised;
-  HDC       hdc;
-  HBITMAP   hbitmap;
-  GdkPixmap *pixmap;
-#else
-  GObject   parent;
-  Display   *xdisplay;
-  GLXPixmap glxpixmap;
-  GdkPixmap *front_left;
-#endif
-};
-
-struct _GdkGLPixmapClass {
-  GObjectClass parent_class;
-};
-typedef struct _GdkGLPixmapClass GdkGLPixmapClass;
-
-static GObjectClass *glpixmap_parent_class;
-
-static void gdk_gl_pixmap_class_init (GdkGLPixmapClass *class);
+/*
+ *  Pixmap support
+ */
 
 GType
 gdk_gl_pixmap_get_type (void)
@@ -585,8 +489,8 @@
 
 #ifdef USE_WIN32
   glFinish ();
-  SelectObject ( pixmap->hdc, pixmap->hbitmap );
-  gdk_pixmap_unref ( pixmap->pixmap );
+  SelectObject (pixmap->hdc, pixmap->hbitmap);
+  gdk_pixmap_unref (pixmap->pixmap);
 #else
   if (pixmap->glxpixmap != None) {
     glXDestroyGLXPixmap(pixmap->xdisplay, pixmap->glxpixmap);
@@ -617,36 +521,29 @@
 GdkGLPixmap *
 gdk_gl_pixmap_new(GdkVisual *visual, GdkPixmap *pixmap)
 {
-#ifdef USE_WIN32
   GdkGLPixmap *glpixmap;
-
-  g_return_val_if_fail(GDK_IS_VISUAL(visual), NULL);
-  g_return_val_if_fail(GDK_IS_PIXMAP(pixmap), NULL);
-
-  glpixmap = g_object_new(GDK_TYPE_GL_PIXMAP, NULL);
-  if (!glpixmap) return NULL;
-
-  glpixmap->initialised = FALSE;
-  glpixmap->hdc = NULL;
-  glpixmap->hbitmap = NULL;
-  glpixmap->pixmap = gdk_pixmap_ref ( pixmap );
-
-  return glpixmap;
-#else
+#ifndef USE_WIN32
   Display *dpy;
   XVisualInfo *vi;
   Pixmap xpixmap;
-  GdkGLPixmap *glpixmap;
   GLXPixmap glxpixmap;
   Window root_return;
   unsigned int x_ret, y_ret, w_ret, h_ret, bw_ret, depth_ret;
+#endif
 
   g_return_val_if_fail(GDK_IS_VISUAL(visual), NULL);
   g_return_val_if_fail(GDK_IS_PIXMAP(pixmap), NULL);
 
   glpixmap = g_object_new(GDK_TYPE_GL_PIXMAP, NULL);
-  if (!glpixmap) return NULL;
+  if (!glpixmap)
+    return NULL;
 
+#ifdef USE_WIN32
+  glpixmap->initialised = FALSE;
+  glpixmap->hdc = NULL;
+  glpixmap->hbitmap = NULL;
+  glpixmap->pixmap = gdk_pixmap_ref (pixmap);
+#else
   dpy = GDK_DISPLAY();
   xpixmap = (Pixmap)GDK_DRAWABLE_XID(pixmap);
   
@@ -666,58 +563,57 @@
   glpixmap->xdisplay   = dpy;
   glpixmap->glxpixmap  = glxpixmap;
   glpixmap->front_left = gdk_pixmap_ref(pixmap);
+#endif
 
   return glpixmap;
-#endif
 }
 
 
 gint gdk_gl_pixmap_make_current(GdkGLPixmap *glpixmap, GdkGLContext *context)
 {
-#ifdef USE_WIN32
-  g_return_val_if_fail (GDK_IS_GL_PIXMAP(glpixmap), FALSE );
-  g_return_val_if_fail (GDK_IS_GL_CONTEXT(context), FALSE );
+#ifndef USE_WIN32
+  Display  *dpy;
+  GLXPixmap glxpixmap;
+  GLXContext glxcontext;
+#endif
+
+  g_return_val_if_fail (GDK_IS_GL_PIXMAP(glpixmap), FALSE);
+  g_return_val_if_fail (GDK_IS_GL_CONTEXT(context), FALSE);
 
-  if ( !context->initialised )
+#ifdef USE_WIN32
+  if (!context->initialised)
   {
     int pf;
 
-    context->hdc = CreateCompatibleDC ( NULL );
+    context->hdc = CreateCompatibleDC (NULL);
     glpixmap->hdc = context->hdc;
-    glpixmap->hbitmap = SelectObject ( context->hdc, (HBITMAP) gdk_win32_drawable_get_handle ( glpixmap->pixmap ) );
+    glpixmap->hbitmap = SelectObject (context->hdc, (HBITMAP) gdk_win32_drawable_get_handle (glpixmap->pixmap));
 
-    pf = ChoosePixelFormat ( context->hdc, &context->pfd );
+    pf = ChoosePixelFormat (context->hdc, &context->pfd);
 
-    if ( pf != 0 )
+    if (pf != 0)
         {
-          SetPixelFormat ( context->hdc, pf, &context->pfd );
-          context->hglrc = wglCreateContext ( context->hdc );
+          SetPixelFormat (context->hdc, pf, &context->pfd);
+          context->hglrc = wglCreateContext (context->hdc);
         }
 
     if (context->share)
         {
-          if ( context->share->hglrc )
-            wglShareLists ( context->share->hglrc, context->hglrc );
-          gdk_gl_context_unref ( (GdkGLContext*)context->share );
+          if (context->share->hglrc)
+            wglShareLists (context->share->hglrc, context->hglrc);
+          gdk_gl_context_unref ((GdkGLContext*)context->share);
         }
 
     context->initialised = TRUE;
   }
 
-  g_return_val_if_fail ( context->hdc    != NULL, FALSE );
-  g_return_val_if_fail ( context->hglrc  != NULL, FALSE );
+  g_return_val_if_fail (context->hdc    != NULL, FALSE);
+  g_return_val_if_fail (context->hglrc  != NULL, FALSE);
 
-  wglMakeCurrent ( context->hdc, context->hglrc );
+  wglMakeCurrent (context->hdc, context->hglrc);
 
   return TRUE;
 #else
-  Display  *dpy;
-  GLXPixmap glxpixmap;
-  GLXContext glxcontext;
-
-  g_return_val_if_fail(GDK_IS_GL_PIXMAP(glpixmap), FALSE);
-  g_return_val_if_fail(GDK_IS_GL_CONTEXT(context), FALSE);
-
   dpy        = context->xdisplay;
   glxpixmap  = glpixmap->glxpixmap;
   glxcontext = context->glxcontext;
@@ -726,20 +622,140 @@
 #endif
 }
 
-/* fonts */
+/*
+ *  Font support
+ */
+
 void gdk_gl_use_gdk_font(GdkFont *font, int first, int count, int list_base)
 {
 #ifdef USE_WIN32
-  HDC dc = CreateCompatibleDC ( NULL );
-  HFONT old_font = SelectObject ( dc, (void *)gdk_font_id ( font ) );
+  HDC dc = CreateCompatibleDC (NULL);
+  HFONT old_font = SelectObject (dc, (void *)gdk_font_id (font));
 
-  wglUseFontBitmaps ( dc, first, count, list_base );
+  wglUseFontBitmaps (dc, first, count, list_base);
 
-  SelectObject ( dc, old_font );
-  DeleteDC ( dc );
+  SelectObject (dc, old_font);
+  DeleteDC (dc);
 #else
   g_return_if_fail(font != NULL);
   glXUseXFont(gdk_font_id(font), first, count, list_base);
 #endif
 }
 
+
+/*
+ *  Helper functions
+ */
+
+#ifdef USE_WIN32
+static void fill_pfd(PIXELFORMATDESCRIPTOR *pfd, int *attriblist)
+{
+  /*
+   * Ripped from glut's win32_x11.c
+   */
+
+  int *p = attriblist;
+
+  memset(pfd, 0, sizeof(PIXELFORMATDESCRIPTOR));
+  pfd->nSize = (sizeof(PIXELFORMATDESCRIPTOR));
+  pfd->nVersion = 1;
+
+  /* Defaults. */
+  pfd->dwFlags = PFD_SUPPORT_OPENGL | PFD_DRAW_TO_WINDOW;
+  pfd->iPixelType = PFD_TYPE_COLORINDEX;
+  pfd->cColorBits = 32;
+  pfd->cDepthBits = 0;
+  pfd->cAccumBits = 0;
+
+  while (*p) {
+    switch (*p) {
+    case GDK_GL_USE_GL:
+      pfd->dwFlags |= PFD_SUPPORT_OPENGL;
+      break;
+    case GDK_GL_BUFFER_SIZE:
+      pfd->cColorBits = *(++p);
+      break;
+    case GDK_GL_LEVEL:
+      /* the bReserved flag of the pfd contains the
+         overlay/underlay info. */
+      pfd->bReserved = *(++p);
+      break;
+    case GDK_GL_RGBA:
+      pfd->iPixelType = PFD_TYPE_RGBA;
+      break;
+    case GDK_GL_DOUBLEBUFFER:
+      pfd->dwFlags |= PFD_DOUBLEBUFFER;
+      break;
+    case GDK_GL_STEREO:
+      pfd->dwFlags |= PFD_STEREO;
+      break;
+    case GDK_GL_AUX_BUFFERS:
+      pfd->cAuxBuffers = *(++p);
+      break;
+    case GDK_GL_RED_SIZE:
+      pfd->cRedBits = 8; /* Try to get the maximum. */
+      ++p;
+      break;
+    case GDK_GL_GREEN_SIZE:
+      pfd->cGreenBits = 8;
+      ++p;
+      break;
+    case GDK_GL_BLUE_SIZE:
+      pfd->cBlueBits = 8;
+      ++p;
+      break;
+    case GDK_GL_ALPHA_SIZE:
+      pfd->cAlphaBits = 8;
+      ++p;
+      break;
+    case GDK_GL_DEPTH_SIZE:
+      pfd->cDepthBits = 32;
+      ++p;
+      break;
+    case GDK_GL_STENCIL_SIZE:
+      pfd->cStencilBits = *(++p);
+      break;
+    case GDK_GL_ACCUM_RED_SIZE:
+    case GDK_GL_ACCUM_GREEN_SIZE:
+    case GDK_GL_ACCUM_BLUE_SIZE:
+    case GDK_GL_ACCUM_ALPHA_SIZE:
+      /* I believe that WGL only used the cAccumRedBits,
+         cAccumBlueBits, cAccumGreenBits, and cAccumAlphaBits fields
+         when returning info about the accumulation buffer precision.
+         Only cAccumBits is used for requesting an accumulation
+         buffer. */
+      pfd->cAccumBits += *(++p);
+                break;
+    }
+    ++p;
+  }
+}
+
+
+#else
+static XVisualInfo *get_xvisualinfo(GdkVisual *visual)
+{
+  Display *dpy;
+  XVisualInfo vinfo_template;
+  XVisualInfo *vi;
+  int nitems_return;
+
+  dpy = GDK_DISPLAY();
+
+  /* 'GLX uses VisualInfo records because they uniquely identify
+   * a (VisualID,screen,depth) tuple.'
+   */
+  vinfo_template.visual   = GDK_VISUAL_XVISUAL(visual);
+  vinfo_template.visualid = XVisualIDFromVisual(vinfo_template.visual);
+  vinfo_template.depth    = visual->depth;
+  vinfo_template.screen   = DefaultScreen(dpy);
+  vi = XGetVisualInfo(dpy, VisualIDMask|VisualDepthMask|VisualScreenMask,
+		      &vinfo_template, &nitems_return);
+
+  g_assert(vi!=0  && nitems_return==1); /* visualinfo needs to be unique */
+
+  /* remember to XFree returned XVisualInfo !!! */
+  return vi;
+}
+#endif
+