[gtk/wip/chergert/gdk-macos-gl-renderer: 26/26] macos: wait for begin_frame to switch to GL view

[Christian Hergert <chergert src gnome org>]

commit 1db0132482d6987c7d8fdf9d1759a6774197f37b
Author: Christian Hergert <chergert redhat com>
Date:   Wed Oct 28 17:10:16 2020 -0700

    macos: wait for begin_frame to switch to GL view
    
    We don't need the GL view unless we intend on rendering the whole
    surface with GL. This delays until begin_frame to do that (as that is when
    we know the renderer is doing so).
    
    This fixes cairo software rendering with a GtkGLArea.

 gdk/macos/gdkmacosglcontext.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)
---
diff --git a/gdk/macos/gdkmacosglcontext.c b/gdk/macos/gdkmacosglcontext.c
index 9a42d9511a..e1d792a41e 100644
--- a/gdk/macos/gdkmacosglcontext.c
+++ b/gdk/macos/gdkmacosglcontext.c
@@ -154,7 +154,6 @@ gdk_macos_gl_context_real_realize (GdkGLContext  *context,
 {
   GdkMacosGLContext *self = (GdkMacosGLContext *)context;
   GdkSurface *surface;
-  NSView *nsview;
   NSOpenGLContext *shared_gl_context = nil;
   NSOpenGLContext *gl_context;
   NSOpenGLPixelFormat *pixelFormat;
@@ -176,17 +175,9 @@ gdk_macos_gl_context_real_realize (GdkGLContext  *context,
   gdk_gl_context_get_required_version (context, &major, &minor);
 
   surface = gdk_draw_context_get_surface (GDK_DRAW_CONTEXT (context));
-  nsview = _gdk_macos_surface_get_view (GDK_MACOS_SURFACE (surface));
   shared = gdk_gl_context_get_shared_context (context);
   shared_data = gdk_surface_get_shared_data_gl_context (surface);
 
-  /* If we are not attached and have a shared context, then we are
-   * trying to draw to our NSView (which must be a GL view). Ensure
-   * that we have that up front to save some checking later.
-   */
-  if (!self->is_attached && shared != NULL)
-    nsview = ensure_gl_view (self);
-
   if (shared != NULL)
     {
       if (!(shared_gl_context = get_ns_open_gl_context (GDK_MACOS_GL_CONTEXT (shared), error)))
@@ -264,6 +255,14 @@ gdk_macos_gl_context_begin_frame (GdkDrawContext *context,
 
   g_assert (GDK_IS_MACOS_GL_CONTEXT (self));
 
+  /* If begin frame is called, that means we are trying to draw to
+   * the NSWindow using our view. That might be a GdkMacosCairoView
+   * but we need it to be a GL view.
+   */
+  if (!self->is_attached &&
+      gdk_gl_context_get_shared_context (GDK_GL_CONTEXT (context)))
+    ensure_gl_view (self);
+
   if (self->needs_resize)
     {
       self->needs_resize = FALSE;