GtkSnapshot: Reuse snapshot state objects

Rather than allocate new ones all the time we reuse the previous ones.
We just clear them and save them in the parent for later reuse.

diff --git a/gtk/gtksnapshot.c b/gtk/gtksnapshot.c
index e17005828a4c515ee7e2087e5c21d6e8880cf823..72f1b1586f832e8d175f7018996857706e9487ad 100644 (file)
--- a/gtk/gtksnapshot.c
+++ b/gtk/gtksnapshot.c
@@ -84,11 +84,18 @@ gtk_snapshot_state_new (GtkSnapshotState       *parent,
 {
   GtkSnapshotState *state;
 
-  state = g_slice_new0 (GtkSnapshotState);
-
-  state->nodes = g_ptr_array_new_with_free_func ((GDestroyNotify) gsk_render_node_unref);
+  if (parent != NULL && parent->cached_state != NULL)
+    {
+      state = parent->cached_state;
+      parent->cached_state = NULL;
+    }
+  else
+    {
+      state = g_slice_new0 (GtkSnapshotState);
+      state->nodes = g_ptr_array_new_with_free_func ((GDestroyNotify) gsk_render_node_unref);
+      state->parent = parent;
+    }
 
-  state->parent = parent;
   state->name = name;
   if (clip)
     state->clip_region = cairo_region_reference (clip);
@@ -99,16 +106,21 @@ gtk_snapshot_state_new (GtkSnapshotState       *parent,
   return state;
 }
 
+static void
+gtk_snapshot_state_clear (GtkSnapshotState *state)
+{
+  g_ptr_array_set_size (state->nodes, 0);
+  g_clear_pointer (&state->clip_region, cairo_region_destroy);
+  g_clear_pointer (&state->name, g_free);
+}
+
 static void
 gtk_snapshot_state_free (GtkSnapshotState *state)
 {
+  if (state->cached_state)
+    gtk_snapshot_state_free (state->cached_state);
+  gtk_snapshot_state_clear (state);
   g_ptr_array_unref (state->nodes);
-
-  if (state->clip_region)
-    cairo_region_destroy (state->clip_region);
-
-  g_free (state->name);
-
   g_slice_free (GtkSnapshotState, state);
 }
 
@@ -697,7 +709,13 @@ gtk_snapshot_pop (GtkSnapshot *snapshot)
                               state->nodes->len,
                               state->name);
 
-  gtk_snapshot_state_free (state);
+  if (snapshot->state == NULL)
+    gtk_snapshot_state_free (state);
+  else
+    {
+      gtk_snapshot_state_clear (state);
+      snapshot->state->cached_state = state;
+    }
 
   return node;
 }

diff --git a/gtk/gtksnapshotprivate.h b/gtk/gtksnapshotprivate.h
index 31415588baff21ddddd5af7d80811f0bc9c6fdc6..2384a8b55f7d0df8c27076556c006b72ce27e532 100644 (file)
--- a/gtk/gtksnapshotprivate.h
+++ b/gtk/gtksnapshotprivate.h
@@ -31,6 +31,7 @@ typedef GskRenderNode * (* GtkSnapshotCollectFunc) (GtkSnapshotState *state,
 
 struct _GtkSnapshotState {
   GtkSnapshotState      *parent;
+  GtkSnapshotState      *cached_state; /* A cleared state object we can (re)use */
 
   char                  *name;
   GPtrArray             *nodes;