From 0fce30070f84c0cfa8daf87634bba39379def23b Mon Sep 17 00:00:00 2001
From: Benjamin Otte <otte@redhat.com>
Date: Sun, 6 Jun 2021 17:07:05 +0200
Subject: [PATCH] x11: Initialize GL at startup

We need to initialize GL to select the Visual we are going to use for
all our Windows.

As the Visual needs to be known before we know if we are even gonna use
GL later, we can't avoid initializing it.

Note that this previously happened, too. It was just hidden behind the
GdkScreen initialization.
---
 gdk/x11/gdkdisplay-x11.c   | 20 ++++++++++++++++++++
 gdk/x11/gdkglcontext-x11.c | 36 ++++++------------------------------
 gdk/x11/gdkglcontext-x11.h |  2 --
 3 files changed, 26 insertions(+), 32 deletions(-)

diff --git a/gdk/x11/gdkdisplay-x11.c b/gdk/x11/gdkdisplay-x11.c
index 707abe491f..5eaf09ec6b 100644
--- a/gdk/x11/gdkdisplay-x11.c
+++ b/gdk/x11/gdkdisplay-x11.c
@@ -1335,6 +1335,25 @@ set_sm_client_id (GdkDisplay  *display,
                      gdk_x11_get_xatom_by_name_for_display (display, "SM_CLIENT_ID"));
 }
 
+static void
+gdk_x11_display_init_gl (GdkX11Display *self)
+{
+  GdkDisplay *display G_GNUC_UNUSED = GDK_DISPLAY (self);
+
+  if (GDK_DISPLAY_DEBUG_CHECK (display, GL_DISABLE))
+    return;
+
+  if (!GDK_DISPLAY_DEBUG_CHECK (display, GL_GLX))
+    {
+      /* We favour EGL */
+      if (gdk_x11_screen_init_egl (self->screen))
+        return;
+    }
+
+  if (gdk_x11_screen_init_glx (self->screen))
+    return;
+}
+
 /**
  * gdk_x11_display_open:
  * @display_name: (nullable): name of the X display.
@@ -1406,6 +1425,7 @@ gdk_x11_display_open (const char *display_name)
    * as we care about GLX details such as alpha/depth/stencil depth,
    * stereo and double buffering
    */
+  gdk_x11_display_init_gl (display_x11);
   gdk_x11_screen_update_visuals_for_glx (display_x11->screen);
 
   if (display_x11->screen->rgba_visual)
diff --git a/gdk/x11/gdkglcontext-x11.c b/gdk/x11/gdkglcontext-x11.c
index cb87cf8425..b97a77464a 100644
--- a/gdk/x11/gdkglcontext-x11.c
+++ b/gdk/x11/gdkglcontext-x11.c
@@ -54,27 +54,6 @@ gdk_x11_gl_context_init (GdkX11GLContext *self)
   self->do_frame_sync = TRUE;
 }
 
-gboolean
-gdk_x11_screen_init_gl (GdkX11Screen *screen)
-{
-  GdkDisplay *display G_GNUC_UNUSED = GDK_SCREEN_DISPLAY (screen);
-
-  if (GDK_DISPLAY_DEBUG_CHECK (display, GL_DISABLE))
-    return FALSE;
-
-  if (!GDK_DISPLAY_DEBUG_CHECK (display, GL_GLX))
-    {
-      /* We favour EGL */
-      if (gdk_x11_screen_init_egl (screen))
-        return TRUE;
-    }
-
-  if (gdk_x11_screen_init_glx (screen))
-    return TRUE;
-
-  return FALSE;
-}
-
 GdkGLContext *
 gdk_x11_surface_create_gl_context (GdkSurface    *surface,
                                    gboolean       attached,
@@ -86,8 +65,13 @@ gdk_x11_surface_create_gl_context (GdkSurface    *surface,
   GdkDisplay *display;
 
   display = gdk_surface_get_display (surface);
+  display_x11 = GDK_X11_DISPLAY (display);
 
-  if (!gdk_x11_screen_init_gl (GDK_SURFACE_SCREEN (surface)))
+  if (display_x11->have_egl)
+    context = gdk_x11_gl_context_egl_new (surface, attached, share, error);
+  else if (display_x11->have_glx)
+    context = gdk_x11_gl_context_glx_new (surface, attached, share, error);
+  else
     {
       g_set_error_literal (error, GDK_GL_ERROR,
                            GDK_GL_ERROR_NOT_AVAILABLE,
@@ -95,14 +79,6 @@ gdk_x11_surface_create_gl_context (GdkSurface    *surface,
       return NULL;
     }
 
-  display_x11 = GDK_X11_DISPLAY (display);
-  if (display_x11->have_egl)
-    context = gdk_x11_gl_context_egl_new (surface, attached, share, error);
-  else if (display_x11->have_glx)
-    context = gdk_x11_gl_context_glx_new (surface, attached, share, error);
-  else
-    g_assert_not_reached ();
-
   if (context == NULL)
     return NULL;
 
diff --git a/gdk/x11/gdkglcontext-x11.h b/gdk/x11/gdkglcontext-x11.h
index dc6048b3fe..991c361cc5 100644
--- a/gdk/x11/gdkglcontext-x11.h
+++ b/gdk/x11/gdkglcontext-x11.h
@@ -60,8 +60,6 @@ struct _GdkX11GLContextClass
   void (* bind_for_frame_fence) (GdkX11GLContext *self);
 };
 
-gboolean        gdk_x11_screen_init_gl                  (GdkX11Screen  *screen);
-
 GdkGLContext *  gdk_x11_surface_create_gl_context       (GdkSurface    *window,
                                                          gboolean       attached,
                                                          GdkGLContext  *share,
-- 
2.30.2