From 4a281edc872be418824fabf07b074b1a449a2e7a Mon Sep 17 00:00:00 2001
From: Benjamin Otte <otte@redhat.com>
Date: Mon, 17 Sep 2012 11:30:21 +0200
Subject: [PATCH] stylecontext: Only create transitions conditionally

While regular animations should always be created, transitions should
not. This patch allows to express this by passing NULL as the values to
transition from.

It also adds a gtk_style_context_should_create_transitions() function
that returns TRUE when transitions should be created.
---
 gtk/gtkcsscomputedvalues.c |  3 ++-
 gtk/gtkstylecontext.c      | 23 ++++++++++++++++++++++-
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/gtk/gtkcsscomputedvalues.c b/gtk/gtkcsscomputedvalues.c
index 7ec040ea58..cd2f66b2d6 100644
--- a/gtk/gtkcsscomputedvalues.c
+++ b/gtk/gtkcsscomputedvalues.c
@@ -492,7 +492,8 @@ _gtk_css_computed_values_create_animations (GtkCssComputedValues *values,
                                             GtkCssComputedValues *source,
                                             GtkStyleContext      *context)
 {
-  gtk_css_computed_values_create_css_transitions (values, timestamp, source);
+  if (source != NULL)
+    gtk_css_computed_values_create_css_transitions (values, timestamp, source);
   gtk_css_computed_values_create_css_animations (values, timestamp, context);
 }
 
diff --git a/gtk/gtkstylecontext.c b/gtk/gtkstylecontext.c
index e42ac88b12..b06d4d868d 100644
--- a/gtk/gtkstylecontext.c
+++ b/gtk/gtkstylecontext.c
@@ -3077,6 +3077,27 @@ gtk_style_context_needs_full_revalidate (GtkStyleContext  *context,
     return FALSE;
 }
 
+static gboolean
+gtk_style_context_should_create_transitions (GtkStyleContext *context)
+{
+  GtkStyleContextPrivate *priv;
+  gboolean animate;
+
+  priv = context->priv;
+
+  if (priv->widget == NULL)
+    return FALSE;
+
+  if (!gtk_widget_get_mapped (priv->widget))
+    return FALSE;
+
+  g_object_get (gtk_widget_get_settings (context->priv->widget),
+                "gtk-enable-animations", &animate,
+                NULL);
+
+  return animate;
+}
+
 void
 _gtk_style_context_validate (GtkStyleContext  *context,
                              gint64            timestamp,
@@ -3144,7 +3165,7 @@ _gtk_style_context_validate (GtkStyleContext  *context,
 
           _gtk_css_computed_values_create_animations (data->store,
                                                       timestamp,
-                                                      current->store,
+                                                      gtk_style_context_should_create_transitions (context) ? current->store : NULL,
                                                       context);
           if (_gtk_css_computed_values_is_static (data->store))
             change &= ~GTK_CSS_CHANGE_ANIMATE;
-- 
2.30.2