cursor-renderer/native: Let the backend realize cursor sprite itself

It knows better when it's needed. For now, just do it just as before,
before drawing. Eventually, we can conditionalize where to realize
depending on the cursor sprite position.

https://gitlab.gnome.org/GNOME/mutter/issues/77

src/backends/meta-cursor-renderer.c

@@ -283,13 +283,3 @@ meta_cursor_renderer_get_cursor (MetaCursorRenderer *renderer)
 
   return priv->displayed_cursor;
 }
-
-void
-meta_cursor_renderer_realize_cursor_sprite (MetaCursorRenderer *renderer,
-                                            MetaCursorSprite   *cursor_sprite)
-{
-  MetaCursorRendererClass *renderer_class = META_CURSOR_RENDERER_GET_CLASS (renderer);
-
-  if (renderer_class->realize_cursor_sprite)
-    renderer_class->realize_cursor_sprite (renderer, cursor_sprite);
-}

src/backends/meta-cursor-renderer.h

@@ -40,8 +40,6 @@ struct _MetaCursorRendererClass
 
   gboolean (* update_cursor) (MetaCursorRenderer *renderer,
                               MetaCursorSprite   *cursor_sprite);
-  void (* realize_cursor_sprite) (MetaCursorRenderer *renderer,
-                                  MetaCursorSprite   *cursor_sprite);
 };
 
 MetaCursorRenderer * meta_cursor_renderer_new (void);
@@ -60,9 +58,6 @@ MetaCursorSprite * meta_cursor_renderer_get_cursor (MetaCursorRenderer *renderer
 ClutterRect meta_cursor_renderer_calculate_rect (MetaCursorRenderer *renderer,
                                                  MetaCursorSprite   *cursor_sprite);
 
-void meta_cursor_renderer_realize_cursor_sprite (MetaCursorRenderer *renderer,
-                                                 MetaCursorSprite   *cursor_sprite);
-
 void meta_cursor_renderer_emit_painted (MetaCursorRenderer *renderer,
                                         MetaCursorSprite   *cursor_sprite);
 

src/backends/meta-cursor-sprite-xcursor.c

@@ -20,7 +20,6 @@
 
 #include "backends/meta-cursor-sprite-xcursor.h"
 
-#include "backends/meta-backend-private.h"
 #include "backends/meta-cursor.h"
 #include "backends/meta-cursor-renderer.h"
 #include "clutter/clutter.h"
@@ -118,8 +117,6 @@ static void
 load_from_current_xcursor_image (MetaCursorSpriteXcursor *sprite_xcursor)
 {
   MetaCursorSprite *sprite = META_CURSOR_SPRITE (sprite_xcursor);
-  MetaBackend *backend = meta_get_backend ();
-  MetaCursorRenderer *renderer = meta_backend_get_cursor_renderer (backend);
   XcursorImage *xc_image;
   int width, height, rowstride;
   CoglPixelFormat cogl_format;
@@ -160,8 +157,6 @@ load_from_current_xcursor_image (MetaCursorSpriteXcursor *sprite_xcursor)
                                   xc_image->xhot, xc_image->yhot);
 
   g_clear_pointer (&texture, cogl_object_unref);
-
-  meta_cursor_renderer_realize_cursor_sprite (renderer, sprite);
 }
 
 void

src/backends/native/meta-cursor-renderer-native.c

@@ -119,6 +119,10 @@ static GQuark quark_cursor_renderer_native_gpu_data = 0;
 
 G_DEFINE_TYPE_WITH_PRIVATE (MetaCursorRendererNative, meta_cursor_renderer_native, META_TYPE_CURSOR_RENDERER);
 
+static void
+realize_cursor_sprite (MetaCursorRenderer *renderer,
+                       MetaCursorSprite   *cursor_sprite);
+
 static MetaCursorNativeGpuState *
 get_cursor_gpu_state (MetaCursorNativePrivate *cursor_priv,
                       MetaGpuKms              *gpu_kms);
@@ -675,7 +679,7 @@ meta_cursor_renderer_native_update_cursor (MetaCursorRenderer *renderer,
     meta_cursor_renderer_native_get_instance_private (native);
 
   if (cursor_sprite)
-    meta_cursor_sprite_realize_texture (cursor_sprite);
+    realize_cursor_sprite (renderer, cursor_sprite);
 
   maybe_schedule_cursor_sprite_animation_frame (native, cursor_sprite);
 
@@ -717,6 +721,24 @@ ensure_cursor_gpu_state (MetaCursorNativePrivate *cursor_priv,
   return cursor_gpu_state;
 }
 
+static void
+on_cursor_sprite_texture_changed (MetaCursorSprite *cursor_sprite)
+{
+  MetaCursorNativePrivate *cursor_priv = get_cursor_priv (cursor_sprite);
+  GHashTableIter iter;
+  MetaCursorNativeGpuState *cursor_gpu_state;
+
+  g_hash_table_iter_init (&iter, cursor_priv->gpu_states);
+  while (g_hash_table_iter_next (&iter, NULL, (gpointer *) &cursor_gpu_state))
+    {
+      guint pending_bo;
+      pending_bo = get_pending_cursor_sprite_gbm_bo_index (cursor_gpu_state);
+      g_clear_pointer (&cursor_gpu_state->bos[pending_bo],
+                       (GDestroyNotify) gbm_bo_destroy);
+      cursor_gpu_state->pending_bo_state = META_CURSOR_GBM_BO_STATE_INVALIDATED;
+    }
+}
+
 static void
 cursor_priv_free (MetaCursorNativePrivate *cursor_priv)
 {
@@ -749,6 +771,9 @@ ensure_cursor_priv (MetaCursorSprite *cursor_sprite)
                            cursor_priv,
                            (GDestroyNotify) cursor_priv_free);
 
+  g_signal_connect (cursor_sprite, "texture-changed",
+                    G_CALLBACK (on_cursor_sprite_texture_changed), NULL);
+
   return cursor_priv;
 }
 
@@ -816,26 +841,31 @@ load_cursor_sprite_gbm_buffer_for_gpu (MetaCursorRendererNative *native,
     }
 }
 
-static void
+static gboolean
-invalidate_pending_cursor_sprite_gbm_bo (MetaCursorSprite *cursor_sprite,
+is_cursor_hw_state_valid (MetaCursorSprite *cursor_sprite,
                           MetaGpuKms       *gpu_kms)
 {
   MetaCursorNativePrivate *cursor_priv;
   MetaCursorNativeGpuState *cursor_gpu_state;
-  guint pending_bo;
 
   cursor_priv = get_cursor_priv (cursor_sprite);
   if (!cursor_priv)
-    return;
+    return FALSE;
 
   cursor_gpu_state = get_cursor_gpu_state (cursor_priv, gpu_kms);
   if (!cursor_gpu_state)
-    return;
+    return FALSE;
 
-  pending_bo = get_pending_cursor_sprite_gbm_bo_index (cursor_gpu_state);
+  switch (cursor_gpu_state->pending_bo_state)
-  g_clear_pointer (&cursor_gpu_state->bos[pending_bo],
+    {
-                   (GDestroyNotify) gbm_bo_destroy);
+    case META_CURSOR_GBM_BO_STATE_SET:
-  cursor_gpu_state->pending_bo_state = META_CURSOR_GBM_BO_STATE_INVALIDATED;
+    case META_CURSOR_GBM_BO_STATE_NONE:
+      return TRUE;
+    case META_CURSOR_GBM_BO_STATE_INVALIDATED:
+      return FALSE;
+    }
+
+  g_assert_not_reached ();
 }
 
 #ifdef HAVE_WAYLAND
@@ -858,10 +888,8 @@ realize_cursor_sprite_from_wl_buffer_for_gpu (MetaCursorRenderer      *renderer,
   if (!cursor_renderer_gpu_data || cursor_renderer_gpu_data->hw_cursor_broken)
     return;
 
-  /* Destroy any previous pending cursor buffer; we'll always either fail (which
+  if (is_cursor_hw_state_valid (cursor_sprite, gpu_kms))
-   * should unset, or succeed, which will set new buffer.
+    return;
-   */
-  invalidate_pending_cursor_sprite_gbm_bo (cursor_sprite, gpu_kms);
 
   texture = meta_cursor_sprite_get_cogl_texture (cursor_sprite);
   width = cogl_texture_get_width (texture);
@@ -990,7 +1018,8 @@ realize_cursor_sprite_from_xcursor_for_gpu (MetaCursorRenderer      *renderer,
   if (!cursor_renderer_gpu_data || cursor_renderer_gpu_data->hw_cursor_broken)
     return;
 
-  invalidate_pending_cursor_sprite_gbm_bo (cursor_sprite, gpu_kms);
+  if (is_cursor_hw_state_valid (cursor_sprite, gpu_kms))
+    return;
 
   load_cursor_sprite_gbm_buffer_for_gpu (native,
                                          gpu_kms,
@@ -1027,9 +1056,11 @@ realize_cursor_sprite_from_xcursor (MetaCursorRenderer      *renderer,
 }
 
 static void
-meta_cursor_renderer_native_realize_cursor_sprite (MetaCursorRenderer *renderer,
+realize_cursor_sprite (MetaCursorRenderer *renderer,
                        MetaCursorSprite   *cursor_sprite)
 {
+  meta_cursor_sprite_realize_texture (cursor_sprite);
+
   if (META_IS_CURSOR_SPRITE_XCURSOR (cursor_sprite))
     {
       MetaCursorSpriteXcursor *sprite_xcursor =
@@ -1056,8 +1087,6 @@ meta_cursor_renderer_native_class_init (MetaCursorRendererNativeClass *klass)
 
   object_class->finalize = meta_cursor_renderer_native_finalize;
   renderer_class->update_cursor = meta_cursor_renderer_native_update_cursor;
-  renderer_class->realize_cursor_sprite =
-    meta_cursor_renderer_native_realize_cursor_sprite;
 
   quark_cursor_sprite = g_quark_from_static_string ("-meta-cursor-native");
   quark_cursor_renderer_native_gpu_data =

src/wayland/meta-wayland-cursor-surface.c

@@ -71,16 +71,6 @@ update_cursor_sprite_texture (MetaWaylandCursorSurface *cursor_surface)
                                       buffer->texture,
                                       priv->hot_x * surface->scale,
                                       priv->hot_y * surface->scale);
-
-      if (priv->buffer)
-        {
-          g_assert (priv->buffer == buffer);
-          meta_cursor_renderer_realize_cursor_sprite (priv->cursor_renderer,
-                                                      cursor_sprite);
-
-          meta_wayland_surface_unref_buffer_use_count (surface);
-          g_clear_object (&priv->buffer);
-        }
     }
   else
     {