Merge branch 'wgl-usage-across-threads-324' into 'gtk-3-24'

3.24: GDK-Win32: Use wrapper functions for calling core wgl* functions (backport from GTK-4.x)

See merge request GNOME/gtk!7284

gdk/win32/gdkglcontext-win32-private.c

@@ -0,0 +1,56 @@
+/* GDK - The GIMP Drawing Kit
+ *
+ * gdkglcontext-win32-wgl-private.c: Win32 specific OpenGL wrappers
+ *
+ * Copyright © 2023 Chun-wei Fan
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * These wrapper functions are used when we don't want to use the wgl*() core functions
+ * that we acquire via libepoxy (such as when we are disposing the underlying WGL context in,
+ * GdkGLContext from different threads, so for these calls, we are actually linking to the
+ * system's/ICD opengl32.dll directly, so that we are guaranteed that the "right" versions of
+ * these WGL calls are carried out.  This must be a separate source file because we can't
+ * include the system's GL/gl.h with epoxy/(w)gl.h together in a single source file.  We
+ * should not need to use these when we are creating/initializing a WGL context in GDK, since
+ * we should be in the same thread at this point.
+ */
+
+#define DONT_INCLUDE_LIBEPOXY
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include <GL/gl.h>
+
+#include "gdkglcontext-win32.h"
+
+void
+gdk_win32_private_wglDeleteContext (HGLRC hglrc)
+{
+  wglDeleteContext (hglrc);
+}
+
+HGLRC
+gdk_win32_private_wglGetCurrentContext (void)
+{
+  return wglGetCurrentContext ();
+}
+
+BOOL
+gdk_win32_private_wglMakeCurrent (HDC   hdc,
+                                  HGLRC hglrc)
+{
+  return wglMakeCurrent (hdc, hglrc);
+}

gdk/win32/gdkglcontext-win32.c

@@ -397,12 +397,12 @@ gdk_win32_gl_context_dispose_wgl (GObject *gobject)
     {
       GdkWindow *window = gdk_gl_context_get_window (context);
 
-      if (wglGetCurrentContext () == context_wgl->wgl_context)
-        wglMakeCurrent (NULL, NULL);
+      if (gdk_win32_private_wglGetCurrentContext () == context_wgl->wgl_context)
+        gdk_win32_private_wglMakeCurrent (NULL, NULL);
 
       GDK_NOTE (OPENGL, g_print ("Destroying WGL context\n"));
 
-      wglDeleteContext (context_wgl->wgl_context);
+      gdk_win32_private_wglDeleteContext (context_wgl->wgl_context);
       context_wgl->wgl_context = NULL;
 
       gdk_win32_gl_context_cleanup (context);
@@ -843,7 +843,7 @@ gdk_win32_display_make_wgl_context_current (GdkDisplay   *display,
 
   if (context == NULL)
     {
-      wglMakeCurrent(NULL, NULL);
+      gdk_win32_private_wglMakeCurrent (NULL, NULL);
 
       return TRUE;
     }
@@ -851,8 +851,8 @@ gdk_win32_display_make_wgl_context_current (GdkDisplay   *display,
   context_win32 = GDK_WIN32_GL_CONTEXT (context);
   window = gdk_gl_context_get_window (context);
 
-  if (!wglMakeCurrent (context_win32->gl_hdc,
-                       GDK_WIN32_GL_CONTEXT_WGL (context)->wgl_context))
+  if (!gdk_win32_private_wglMakeCurrent (context_win32->gl_hdc,
+                                         GDK_WIN32_GL_CONTEXT_WGL (context)->wgl_context))
     {
       GDK_NOTE (OPENGL, g_print ("Making WGL context current failed\n"));
       return FALSE;

gdk/win32/gdkglcontext-win32.h

@@ -21,20 +21,29 @@
 #ifndef __GDK_WIN32_GL_CONTEXT__
 #define __GDK_WIN32_GL_CONTEXT__
 
-#include <epoxy/gl.h>
-#include <epoxy/wgl.h>
+#ifdef DONT_INCLUDE_LIBEPOXY
+# define WIN32_LEAN_AND_MEAN
+# include <windows.h>
+# include <GL/gl.h>
 
-#ifdef GDK_WIN32_ENABLE_EGL
-# include <epoxy/egl.h>
+# include <glib.h>
+#else
+# include <epoxy/gl.h>
+# include <epoxy/wgl.h>
+
+# ifdef GDK_WIN32_ENABLE_EGL
+#  include <epoxy/egl.h>
+# endif
+
+# include "gdkglcontextprivate.h"
+# include "gdkdisplayprivate.h"
+# include "gdkvisual.h"
+# include "gdkwindow.h"
 #endif
 
-#include "gdkglcontextprivate.h"
-#include "gdkdisplayprivate.h"
-#include "gdkvisual.h"
-#include "gdkwindow.h"
-
 G_BEGIN_DECLS
 
+#ifndef DONT_INCLUDE_LIBEPOXY
 void
 gdk_win32_window_invalidate_egl_framebuffer (GdkWindow      *window);
 
@@ -52,6 +61,14 @@ gboolean
 gdk_win32_display_make_gl_context_current   (GdkDisplay     *display,
                                              GdkGLContext   *context);
 
+#endif /* !DONT_INCLUDE_LIBEPOXY */
+
+HGLRC     gdk_win32_private_wglGetCurrentContext (void);
+BOOL      gdk_win32_private_wglMakeCurrent       (HDC hdc,
+                                                  HGLRC hglrc);
+void      gdk_win32_private_wglDeleteContext     (HGLRC hglrc);
+
+
 G_END_DECLS
 
 #endif /* __GDK_WIN32_GL_CONTEXT__ */

gdk/win32/meson.build

@@ -11,6 +11,7 @@ gdk_win32_sources = files(
   'gdkevents-win32.c',
   'gdkgeometry-win32.c',
   'gdkglcontext-win32.c',
+  'gdkglcontext-win32-private.c',
   'gdkglobals-win32.c',
   'gdkkeys-win32.c',
   'gdkkeys-win32-impl.c',