[mutter/wip/split-cursor-tracker: 2/2] cursor-tracker: Properly handle invisible cursors

[Rui Matos <rtcm src gnome org>]

commit b9d798c2134f208035edfa8c13fc833486c8b444
Author: Rui Matos <tiagomatos gmail com>
Date:   Mon Apr 7 18:40:41 2014 +0200

    cursor-tracker: Properly handle invisible cursors
    
    We might be asked to not display the cursor ourselves but we should
    still emit cursor-changed signals and hand out the correct sprite and
    hot point information when asked so that consumers can still draw an
    updated cursor themselves.
    
    This fixes the cursor not showing up in gnome-shell's zoom mode.

 src/backends/meta-cursor-tracker-private.h |    6 ++++
 src/backends/meta-cursor-tracker.c         |   44 ++++++++++++++++++---------
 2 files changed, 35 insertions(+), 15 deletions(-)
---
diff --git a/src/backends/meta-cursor-tracker-private.h b/src/backends/meta-cursor-tracker-private.h
index c2a25e9..9564bce 100644
--- a/src/backends/meta-cursor-tracker-private.h
+++ b/src/backends/meta-cursor-tracker-private.h
@@ -46,6 +46,12 @@ struct _MetaCursorTracker {
    */
   MetaCursorReference *displayed_cursor;
 
+  /* This is the cursor that would be displayed if we hadn't been
+   * asked to hide it. i.e. it's the same as displayed_cursor unless
+   * is_showing is false.
+   */
+  MetaCursorReference *current_cursor;
+
   MetaCursorReference *grab_cursor;
 
   /* Wayland clients can set a NULL buffer as their cursor
diff --git a/src/backends/meta-cursor-tracker.c b/src/backends/meta-cursor-tracker.c
index c0d5072..a26280b 100644
--- a/src/backends/meta-cursor-tracker.c
+++ b/src/backends/meta-cursor-tracker.c
@@ -157,8 +157,8 @@ meta_cursor_tracker_get_sprite (MetaCursorTracker *tracker)
 
   META_CURSOR_TRACKER_GET_CLASS (tracker)->ensure_cursor (tracker);
 
-  if (tracker->displayed_cursor)
-    return meta_cursor_reference_get_cogl_texture (tracker->displayed_cursor, NULL, NULL);
+  if (tracker->current_cursor)
+    return meta_cursor_reference_get_cogl_texture (tracker->current_cursor, NULL, NULL);
   else
     return NULL;
 }
@@ -179,8 +179,8 @@ meta_cursor_tracker_get_hot (MetaCursorTracker *tracker,
 
   META_CURSOR_TRACKER_GET_CLASS (tracker)->ensure_cursor (tracker);
 
-  if (tracker->displayed_cursor)
-    meta_cursor_reference_get_cogl_texture (tracker->displayed_cursor, x, y);
+  if (tracker->current_cursor)
+    meta_cursor_reference_get_cogl_texture (tracker->current_cursor, x, y);
   else
     {
       if (x)
@@ -239,11 +239,8 @@ meta_cursor_tracker_set_root_cursor (MetaCursorTracker   *tracker,
 }
 
 static MetaCursorReference *
-get_displayed_cursor (MetaCursorTracker *tracker)
+get_current_cursor (MetaCursorTracker *tracker)
 {
-  if (!tracker->is_showing)
-    return NULL;
-
   if (tracker->grab_cursor)
     return tracker->grab_cursor;
 
@@ -253,21 +250,38 @@ get_displayed_cursor (MetaCursorTracker *tracker)
   return tracker->root_cursor;
 }
 
+static MetaCursorReference *
+get_displayed_cursor (MetaCursorTracker *tracker)
+{
+  if (!tracker->is_showing)
+    return NULL;
+
+  return get_current_cursor (tracker);
+}
+
 void
 _meta_cursor_tracker_sync_cursor (MetaCursorTracker *tracker)
 {
+  MetaCursorReference *current_cursor = get_current_cursor (tracker);
   MetaCursorReference *displayed_cursor = get_displayed_cursor (tracker);
 
-  if (tracker->displayed_cursor == displayed_cursor)
-    return;
+  if (tracker->displayed_cursor != displayed_cursor)
+    {
+      g_clear_pointer (&tracker->displayed_cursor, meta_cursor_reference_unref);
+      if (displayed_cursor)
+        tracker->displayed_cursor = meta_cursor_reference_ref (displayed_cursor);
 
-  g_clear_pointer (&tracker->displayed_cursor, meta_cursor_reference_unref);
-  if (displayed_cursor)
-    tracker->displayed_cursor = meta_cursor_reference_ref (displayed_cursor);
+      META_CURSOR_TRACKER_GET_CLASS (tracker)->sync_cursor (tracker);
+    }
 
-  META_CURSOR_TRACKER_GET_CLASS (tracker)->sync_cursor (tracker);
+  if (tracker->current_cursor != current_cursor)
+    {
+      g_clear_pointer (&tracker->current_cursor, meta_cursor_reference_unref);
+      if (current_cursor)
+        tracker->current_cursor = meta_cursor_reference_ref (current_cursor);
 
-  g_signal_emit (tracker, signals[CURSOR_CHANGED], 0);
+      g_signal_emit (tracker, signals[CURSOR_CHANGED], 0);
+    }
 }
 
 void