[gnome-shell] st-entry: Add support for the text-shadow CSS property

[Cosimo Cecchi <cosimoc src gnome org>]

commit 8783654b3843f07d815b87d37081044eb4cff7f6
Author: Mario Sanchez Prada <mario endlessm com>
Date:   Mon Jun 5 18:39:21 2017 +0100

    st-entry: Add support for the text-shadow CSS property
    
    It's supported everywhere else, we should also support it here.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=783484

 src/st/st-entry.c |   91 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 91 insertions(+), 0 deletions(-)
---
diff --git a/src/st/st-entry.c b/src/st/st-entry.c
index d81463d..82cf5c2 100644
--- a/src/st/st-entry.c
+++ b/src/st/st-entry.c
@@ -106,6 +106,10 @@ struct _StEntryPrivate
   gboolean      hint_visible;
   gboolean      capslock_warning_shown;
   gboolean      has_ibeam;
+
+  CoglHandle    text_shadow_material;
+  gfloat        shadow_width;
+  gfloat        shadow_height;
 };
 
 static guint entry_signals[LAST_SIGNAL] = { 0, };
@@ -245,8 +249,15 @@ static void
 st_entry_dispose (GObject *object)
 {
   StEntry *entry = ST_ENTRY (object);
+  StEntryPrivate *priv = ST_ENTRY_PRIV (entry);
   GdkKeymap *keymap;
 
+  if (priv->text_shadow_material != COGL_INVALID_HANDLE)
+    {
+      cogl_handle_unref (priv->text_shadow_material);
+      priv->text_shadow_material = COGL_INVALID_HANDLE;
+    }
+
   keymap = gdk_keymap_get_for_display (gdk_display_get_default ());
   g_signal_handlers_disconnect_by_func (keymap, keymap_state_changed, entry);
 
@@ -274,6 +285,12 @@ st_entry_style_changed (StWidget *self)
   gchar *font_string, *font_name;
   gdouble size;
 
+  if (priv->text_shadow_material != COGL_INVALID_HANDLE)
+    {
+      cogl_handle_unref (priv->text_shadow_material);
+      priv->text_shadow_material = COGL_INVALID_HANDLE;
+    }
+
   theme_node = st_widget_get_theme_node (self);
  
   st_theme_node_get_foreground_color (theme_node, &color);
@@ -553,6 +570,22 @@ clutter_text_password_char_cb (GObject    *object,
 }
 
 static void
+clutter_text_changed_cb (GObject    *object,
+                         GParamSpec *pspec,
+                         gpointer    user_data)
+{
+  StEntry *entry = ST_ENTRY (user_data);
+  StEntryPrivate *priv = ST_ENTRY_PRIV (entry);
+
+  /* Since the text changed, force a regen of the shadow texture */
+  if (priv->text_shadow_material != COGL_INVALID_HANDLE)
+    {
+      cogl_handle_unref (priv->text_shadow_material);
+      priv->text_shadow_material = COGL_INVALID_HANDLE;
+    }
+}
+
+static void
 st_entry_clipboard_callback (StClipboard *clipboard,
                              const gchar *text,
                              gpointer     data)
@@ -768,6 +801,56 @@ st_entry_leave_event (ClutterActor         *actor,
 }
 
 static void
+st_entry_paint (ClutterActor *actor)
+{
+  StEntryPrivate *priv = ST_ENTRY_PRIV (actor);
+  StThemeNode *theme_node = st_widget_get_theme_node (ST_WIDGET (actor));
+  StShadow *shadow_spec = st_theme_node_get_text_shadow (theme_node);
+  ClutterActorClass *parent_class;
+
+  st_widget_paint_background (ST_WIDGET (actor));
+
+  if (shadow_spec)
+    {
+      ClutterActorBox allocation;
+      float width, height;
+
+      clutter_actor_get_allocation_box (priv->entry, &allocation);
+      clutter_actor_box_get_size (&allocation, &width, &height);
+
+      if (priv->text_shadow_material == COGL_INVALID_HANDLE ||
+          width != priv->shadow_width ||
+          height != priv->shadow_height)
+        {
+          CoglHandle material;
+
+          if (priv->text_shadow_material != COGL_INVALID_HANDLE)
+            cogl_handle_unref (priv->text_shadow_material);
+
+          material = _st_create_shadow_pipeline_from_actor (shadow_spec,
+                                                            priv->entry);
+
+          priv->shadow_width = width;
+          priv->shadow_height = height;
+          priv->text_shadow_material = material;
+        }
+
+      if (priv->text_shadow_material != COGL_INVALID_HANDLE)
+        _st_paint_shadow_with_opacity (shadow_spec,
+                                       priv->text_shadow_material,
+                                       &allocation,
+                                       clutter_actor_get_paint_opacity (priv->entry));
+    }
+
+  /* Since we paint the background ourselves, chain to the parent class
+   * of StWidget, to avoid painting it twice.
+   * This is needed as we still want to paint children.
+   */
+  parent_class = g_type_class_peek_parent (st_entry_parent_class);
+  parent_class->paint (actor);
+}
+
+static void
 st_entry_unmap (ClutterActor *actor)
 {
   StEntryPrivate *priv = ST_ENTRY_PRIV (actor);
@@ -793,6 +876,7 @@ st_entry_class_init (StEntryClass *klass)
   actor_class->get_preferred_width = st_entry_get_preferred_width;
   actor_class->get_preferred_height = st_entry_get_preferred_height;
   actor_class->allocate = st_entry_allocate;
+  actor_class->paint = st_entry_paint;
   actor_class->unmap = st_entry_unmap;
 
   actor_class->key_press_event = st_entry_key_press_event;
@@ -915,8 +999,15 @@ st_entry_init (StEntry *entry)
   g_signal_connect (priv->entry, "button-press-event",
                     G_CALLBACK (clutter_text_button_press_event), entry);
 
+  g_signal_connect (priv->entry, "notify::text",
+                    G_CALLBACK (clutter_text_changed_cb), entry);
+
   priv->spacing = 6.0f;
 
+  priv->text_shadow_material = COGL_INVALID_HANDLE;
+  priv->shadow_width = -1.;
+  priv->shadow_height = -1.;
+
   clutter_actor_add_child (CLUTTER_ACTOR (entry), priv->entry);
   clutter_actor_set_reactive ((ClutterActor *) entry, TRUE);