gdkdisplay-win32.c: Don't retry WGL initializationfix-wgl-cairo-fallback

On Windows, GLES is not that widely available unless one installs wrapper
libraries such as libANGLE, so GLES/EGL support on Windows is used more like
a fallback mode if Desktop OpenGL (WGL) support is inadequate on the system.

Hence, unless one forces WGL or EGL, we will first try to initialize WGL, and
then try to initialize GLES if enabled and if WGL initialization failed, and
then just return whatever the last result we can obtain from these
initialization attempts, since unlike X11 EGL contexts, we do not have
separate modes for WGL except for legacy and non-legacy contexts.

1 files changed, 9 insertions, 7 deletions

diff --git a/gdk/win32/gdkdisplay-win32.c b/gdk/win32/gdkdisplay-win32.c
index 84d99b78a6..cffd85d432 100644
--- a/gdk/win32/gdkdisplay-win32.c
+++ b/gdk/win32/gdkdisplay-win32.c
@@ -1150,6 +1150,8 @@ static gboolean
 gdk_win32_display_init_gl_backend (GdkDisplay  *display,
                                    GError     **error)
 {
+  gboolean result = FALSE;
+
 #ifdef GDK_WIN32_ENABLE_EGL
   if (GDK_DISPLAY_DEBUG_CHECK (display, GL_EGL))
     return gdk_win32_display_init_egl (display, error);
@@ -1161,17 +1163,17 @@ gdk_win32_display_init_gl_backend (GdkDisplay  *display,
    * as WGL is the more tried-and-tested configuration.
    */
 
-  if (gdk_win32_display_init_wgl (display, error))
-    return TRUE;
-  g_clear_error (error);
+  result = gdk_win32_display_init_wgl (display, error);
 
 #ifdef GDK_WIN32_ENABLE_EGL
-  if (gdk_win32_display_init_egl (display, error))
-    return TRUE;
+  if (!result)
+    {
+      g_clear_error (error);
+      result = gdk_win32_display_init_egl (display, error);
+    }
 #endif
-  g_clear_error (error);
 
-  return gdk_win32_display_init_wgl (display, error);
+  return result;
 }
 
 static GdkGLContext *