actor: Add ActorMeta, a base class for actor modifiers

ClutterActorMeta is a base, abstract class that can be used to derive
classes that are attached to a ClutterActor instance in order to modify
the way an actor is painted, sized/positioned or responds to events.

A typed container for ActorMeta instances is also provided to the
sub-classes can be attached to an Actor.

clutter/Makefile.am

@@ -65,6 +65,7 @@ AM_CFLAGS = $(CLUTTER_CFLAGS) $(MAINTAINER_CFLAGS) $(GCOV_CFLAGS)
 
 # please, keep this sorted alphabetically
 source_h =					\
+	$(srcdir)/clutter-actor-meta.h		\
 	$(srcdir)/clutter-actor.h		\
 	$(srcdir)/clutter-alpha.h		\
 	$(srcdir)/clutter-animatable.h          \
@@ -138,6 +139,7 @@ include $(top_srcdir)/build/autotools/Makefile.am.enums
 
 # please, keep this sorted alphabetically
 source_c = \
+	$(srcdir)/clutter-actor-meta.c		\
 	$(srcdir)/clutter-actor.c		\
 	$(srcdir)/clutter-alpha.c 		\
 	$(srcdir)/clutter-animatable.c		\
@@ -206,6 +208,7 @@ source_c_priv = \
 	$(NULL)
 
 source_h_priv = \
+	$(srcdir)/clutter-actor-meta-private.h	\
 	$(srcdir)/clutter-bezier.h		\
 	$(srcdir)/clutter-debug.h 		\
 	$(srcdir)/clutter-keysyms-table.h	\

clutter/clutter-actor-meta-private.h

@@ -0,0 +1,42 @@
+#ifndef __CLUTTER_ACTOR_META_PRIVATE_H__
+#define __CLUTTER_ACTOR_META_PRIVATE_H__
+
+#include <clutter/clutter-actor-meta.h>
+
+G_BEGIN_DECLS
+
+#define CLUTTER_TYPE_META_GROUP         (_clutter_meta_group_get_type ())
+#define CLUTTER_META_GROUP(obj)         (G_TYPE_CHECK_INSTANCE_CAST ((obj), CLUTTER_TYPE_META_GROUP, ClutterMetaGroup))
+#define CLUTTER_IS_META_GROUP(obj)      (G_TYPE_CHECK_INSTANCE_TYPE ((obj), CLUTTER_TYPE_META_GROUP))
+
+typedef struct _ClutterMetaGroup        ClutterMetaGroup;
+typedef struct _ClutterMetaGroupClass   ClutterMetaGroupClass;
+
+struct _ClutterMetaGroup
+{
+  GObject parent_instance;
+
+  ClutterActor *actor;
+
+  GList *meta;
+};
+
+struct _ClutterMetaGroupClass
+{
+  GObjectClass parent_class;
+};
+
+GType _clutter_meta_group_get_type (void) G_GNUC_CONST;
+
+void                  _clutter_meta_group_add_meta    (ClutterMetaGroup *group,
+                                                       ClutterActorMeta *meta);
+void                  _clutter_meta_group_remove_meta (ClutterMetaGroup *group,
+                                                       ClutterActorMeta *meta);
+G_CONST_RETURN GList *_clutter_meta_group_peek_metas  (ClutterMetaGroup *group);
+void                  _clutter_meta_group_clear_metas (ClutterMetaGroup *group);
+ClutterActorMeta *    _clutter_meta_group_get_meta    (ClutterMetaGroup *group,
+                                                       const gchar      *name);
+
+G_END_DECLS
+
+#endif /* __CLUTTER_ACTOR_META_PRIVATE_H__ */

clutter/clutter-actor-meta.c

@@ -0,0 +1,413 @@
+/**
+ * SECTION:ClutterActorMeta
+ * @Title: ClutterActorMeta
+ * @Short_Description: Base class of actor modifiers
+ *
+ * #ClutterActorMeta is an abstract class providing a common API for
+ * modifiers of #ClutterActor
+ *
+ * A #ClutterActorMeta can only be owned by a single #ClutterActor at
+ * any time
+ *
+ * #ClutterActorMeta is available since Clutter 1.4
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "clutter-actor-meta-private.h"
+
+#include "clutter-debug.h"
+#include "clutter-private.h"
+
+struct _ClutterActorMetaPrivate
+{
+  ClutterActor *actor;
+
+  gchar *name;
+
+  guint is_enabled : 1;
+};
+
+enum
+{
+  PROP_0,
+
+  PROP_ACTOR,
+  PROP_NAME,
+  PROP_ENABLED
+};
+
+G_DEFINE_ABSTRACT_TYPE (ClutterActorMeta,
+                        clutter_actor_meta,
+                        G_TYPE_INITIALLY_UNOWNED);
+
+static void
+clutter_actor_meta_real_set_actor (ClutterActorMeta *meta,
+                                   ClutterActor     *actor)
+{
+  meta->priv->actor = actor;
+}
+
+static void
+clutter_actor_meta_set_property (GObject      *gobject,
+                                 guint         prop_id,
+                                 const GValue *value,
+                                 GParamSpec   *pspec)
+{
+  ClutterActorMeta *meta = CLUTTER_ACTOR_META (gobject);
+
+  switch (prop_id)
+    {
+    case PROP_NAME:
+      clutter_actor_meta_set_name (meta, g_value_get_string (value));
+      break;
+
+    case PROP_ENABLED:
+      clutter_actor_meta_set_enabled (meta, g_value_get_boolean (value));
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+clutter_actor_meta_get_property (GObject    *gobject,
+                                 guint       prop_id,
+                                 GValue     *value,
+                                 GParamSpec *pspec)
+{
+  ClutterActorMeta *meta = CLUTTER_ACTOR_META (gobject);
+
+  switch (prop_id)
+    {
+    case PROP_ACTOR:
+      g_value_set_object (value, meta->priv->actor);
+      break;
+
+    case PROP_NAME:
+      g_value_set_string (value, meta->priv->name);
+      break;
+
+    case PROP_ENABLED:
+      g_value_set_boolean (value, meta->priv->is_enabled);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+clutter_actor_meta_finalize (GObject *gobject)
+{
+  ClutterActorMetaPrivate *priv = CLUTTER_ACTOR_META (gobject)->priv;
+
+  g_free (priv->name);
+
+  G_OBJECT_CLASS (clutter_actor_meta_parent_class)->finalize (gobject);
+}
+
+void
+clutter_actor_meta_class_init (ClutterActorMetaClass *klass)
+{
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+  GParamSpec *pspec;
+
+  g_type_class_add_private (klass, sizeof (ClutterActorMetaPrivate));
+
+  klass->set_actor = clutter_actor_meta_real_set_actor;
+
+  gobject_class->set_property = clutter_actor_meta_set_property;
+  gobject_class->get_property = clutter_actor_meta_get_property;
+  gobject_class->finalize = clutter_actor_meta_finalize;
+
+  /**
+   * ClutterActorMeta:actor:
+   *
+   * The #ClutterActor attached to the #ClutterActorMeta instance
+   *
+   * Since: 1.4
+   */
+  pspec = g_param_spec_object ("actor",
+                               "Actor",
+                               "The actor attached to the meta",
+                               CLUTTER_TYPE_ACTOR,
+                               CLUTTER_PARAM_READABLE);
+  g_object_class_install_property (gobject_class, PROP_ACTOR, pspec);
+
+  /**
+   * ClutterActorMeta:name:
+   *
+   * The unique name to access the #ClutterActorMeta
+   *
+   * Since: 1.4
+   */
+  pspec = g_param_spec_string ("name",
+                               "Name",
+                               "The name of the meta",
+                               NULL,
+                               CLUTTER_PARAM_READWRITE |
+                               G_PARAM_CONSTRUCT_ONLY);
+  g_object_class_install_property (gobject_class, PROP_NAME, pspec);
+
+  /**
+   * ClutterActorMeta:enabled:
+   *
+   * Whether or not the #ClutterActorMeta is enabled
+   *
+   * Since: 1.4
+   */
+  pspec = g_param_spec_boolean ("enabled",
+                                "Enabled",
+                                "Whether the meta is enabled",
+                                TRUE,
+                                CLUTTER_PARAM_READWRITE);
+  g_object_class_install_property (gobject_class, PROP_ENABLED, pspec);
+}
+
+void
+clutter_actor_meta_init (ClutterActorMeta *self)
+{
+  self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self,
+                                            CLUTTER_TYPE_ACTOR_META,
+                                            ClutterActorMetaPrivate);
+
+  self->priv->is_enabled = TRUE;
+}
+
+/**
+ * clutter_actor_meta_set_name:
+ * @meta: a #ClutterActorMeta
+ * @name: the name of @meta
+ *
+ * Sets the name of @meta
+ *
+ * The name can be used to identify the #ClutterActorMeta instance
+ *
+ * Since: 1.4
+ */
+void
+clutter_actor_meta_set_name (ClutterActorMeta *meta,
+                             const gchar      *name)
+{
+  g_return_if_fail (CLUTTER_IS_ACTOR_META (meta));
+
+  if (g_strcmp0 (meta->priv->name, name) == 0)
+    return;
+
+  g_free (meta->priv->name);
+  meta->priv->name = g_strdup (name);
+
+  g_object_notify (G_OBJECT (meta), "name");
+}
+
+/**
+ * clutter_actor_meta_get_name:
+ * @meta: a #ClutterActorMeta
+ *
+ * Retrieves the name set using clutter_actor_meta_set_name()
+ *
+ * Return value: (transfer none): the name of the #ClutterActorMeta
+ *   instance, or %NULL if none was set. The returned string is owned
+ *   by the #ClutterActorMeta instance and it should not be modified
+ *   or freed
+ *
+ * Since: 1.4
+ */
+G_CONST_RETURN gchar *
+clutter_actor_meta_get_name (ClutterActorMeta *meta)
+{
+  g_return_val_if_fail (CLUTTER_IS_ACTOR_META (meta), NULL);
+
+  return meta->priv->name;
+}
+
+/**
+ * clutter_actor_meta_set_enabled:
+ * @meta: a #ClutterActorMeta
+ * @is_enabled: whether @meta is enabled
+ *
+ * Sets whether @meta should be enabled or not
+ *
+ * Since: 1.4
+ */
+void
+clutter_actor_meta_set_enabled (ClutterActorMeta *meta,
+                                gboolean          is_enabled)
+{
+  g_return_if_fail (CLUTTER_IS_ACTOR_META (meta));
+
+  is_enabled = !!is_enabled;
+
+  if (meta->priv->is_enabled == is_enabled)
+    return;
+
+  meta->priv->is_enabled = is_enabled;
+
+  g_object_notify (G_OBJECT (meta), "enabled");
+}
+
+/**
+ * clutter_actor_meta_get_enabled:
+ * @meta: a #ClutterActorMeta
+ *
+ * Retrieves whether @meta is enabled
+ *
+ * Return value: %TRUE if the #ClutterActorMeta instance is enabled
+ *
+ * Since: 1.4
+ */
+gboolean
+clutter_actor_meta_get_enabled (ClutterActorMeta *meta)
+{
+  g_return_val_if_fail (CLUTTER_IS_ACTOR_META (meta), FALSE);
+
+  return meta->priv->is_enabled;
+}
+
+/*
+ * _clutter_actor_meta_set_actor
+ * @meta: a #ClutterActorMeta
+ * @actor: a #ClutterActor or %NULL
+ *
+ * Sets or unsets a back pointer to the #ClutterActor that owns
+ * the @meta
+ *
+ * Since: 1.4
+ */
+void
+_clutter_actor_meta_set_actor (ClutterActorMeta *meta,
+                               ClutterActor     *actor)
+{
+  g_return_if_fail (CLUTTER_IS_ACTOR_META (meta));
+  g_return_if_fail (actor == NULL || CLUTTER_IS_ACTOR (actor));
+
+  CLUTTER_ACTOR_META_GET_CLASS (meta)->set_actor (meta, actor);
+}
+
+/**
+ * clutter_actor_meta_get_actor:
+ * @meta: a #ClutterActorMeta
+ *
+ * Retrieves a pointer to the #ClutterActor that owns @meta
+ *
+ * Return value: (transfer none): a pointer to a #ClutterActor or %NULL
+ *
+ * Since: 1.4
+ */
+ClutterActor *
+clutter_actor_meta_get_actor (ClutterActorMeta *meta)
+{
+  g_return_val_if_fail (CLUTTER_IS_ACTOR_META (meta), NULL);
+
+  return meta->priv->actor;
+}
+
+G_DEFINE_TYPE (ClutterMetaGroup, _clutter_meta_group, G_TYPE_OBJECT);
+
+static void
+_clutter_meta_group_dispose (GObject *gobject)
+{
+  _clutter_meta_group_clear_metas (CLUTTER_META_GROUP (gobject));
+
+  G_OBJECT_CLASS (_clutter_meta_group_parent_class)->dispose (gobject);
+}
+
+static void
+_clutter_meta_group_class_init (ClutterMetaGroupClass *klass)
+{
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+
+  gobject_class->dispose = _clutter_meta_group_dispose;
+}
+
+static void
+_clutter_meta_group_init (ClutterMetaGroup *self)
+{
+}
+
+void
+_clutter_meta_group_add_meta (ClutterMetaGroup *group,
+                              ClutterActorMeta *meta)
+{
+  if (meta->priv->actor != NULL)
+    {
+      g_warning ("The meta of type '%s' with name '%s' is "
+                 "already attached to actor '%s'",
+                 G_OBJECT_TYPE_NAME (meta),
+                 meta->priv->name != NULL
+                   ? meta->priv->name
+                   : "<unknown>",
+                 clutter_actor_get_name (meta->priv->actor) != NULL
+                   ? clutter_actor_get_name (meta->priv->actor)
+                   : G_OBJECT_TYPE_NAME (meta->priv->actor));
+      return;
+    }
+
+  group->meta = g_list_append (group->meta, meta);
+  g_object_ref_sink (meta);
+
+  _clutter_actor_meta_set_actor (meta, group->actor);
+}
+
+void
+_clutter_meta_group_remove_meta (ClutterMetaGroup *group,
+                                 ClutterActorMeta *meta)
+{
+  if (meta->priv->actor != group->actor)
+    {
+      g_warning ("The meta of type '%s' with name '%s' is not "
+                 "attached to the actor '%s'",
+                 G_OBJECT_TYPE_NAME (meta),
+                 meta->priv->name != NULL
+                   ? meta->priv->name
+                   : "<unknown>",
+                 clutter_actor_get_name (group->actor) != NULL
+                   ? clutter_actor_get_name (group->actor)
+                   : G_OBJECT_TYPE_NAME (group->actor));
+      return;
+    }
+
+  _clutter_actor_meta_set_actor (meta, NULL);
+
+  group->meta = g_list_remove (group->meta, meta);
+  g_object_unref (meta);
+}
+
+G_CONST_RETURN GList *
+_clutter_meta_group_peek_metas (ClutterMetaGroup *group)
+{
+  return group->meta;
+}
+
+void
+_clutter_meta_group_clear_metas (ClutterMetaGroup *group)
+{
+  g_list_foreach (group->meta, (GFunc) _clutter_actor_meta_set_actor, NULL);
+
+  g_list_foreach (group->meta, (GFunc) g_object_unref, NULL);
+  g_list_free (group->meta);
+  group->meta = NULL;
+}
+
+ClutterActorMeta *
+_clutter_meta_group_get_meta (ClutterMetaGroup *group,
+                              const gchar      *name)
+{
+  GList *l;
+
+  for (l = group->meta; l != NULL; l = l->next)
+    {
+      ClutterActorMeta *meta = l->data;
+
+      if (g_strcmp0 (meta->priv->name, name) == 0)
+        return meta;
+    }
+
+  return NULL;
+}

clutter/clutter-actor-meta.h

@@ -0,0 +1,84 @@
+#if !defined(__CLUTTER_H_INSIDE__) && !defined(CLUTTER_COMPILATION)
+#error "Only <clutter/clutter.h> can be included directly."
+#endif
+
+#ifndef __CLUTTER_ACTOR_META_H__
+#define __CLUTTER_ACTOR_META_H__
+
+#include <clutter/clutter-types.h>
+
+G_BEGIN_DECLS
+
+#define CLUTTER_TYPE_ACTOR_META                 (clutter_actor_meta_get_type ())
+#define CLUTTER_ACTOR_META(obj)                 (G_TYPE_CHECK_INSTANCE_CAST ((obj), CLUTTER_TYPE_ACTOR_META, ClutterActorMeta))
+#define CLUTTER_IS_ACTOR_META(obj)              (G_TYPE_CHECK_INSTANCE_TYPE ((obj), CLUTTER_TYPE_ACTOR_META))
+#define CLUTTER_ACTOR_META_CLASS(klass)         (G_TYPE_CHECK_CLASS_CAST ((klass), CLUTTER_TYPE_ACTOR_META, ClutterActorMetaClass))
+#define CLUTTER_IS_ACTOR_META_CLASS(klass)      (G_TYPE_CHECK_CLASS_TYPE ((klass), CLUTTER_TYPE_ACTOR_META))
+#define CLUTTER_ACTOR_META_GET_CLASS(obj)       (G_TYPE_INSTANCE_GET_CLASS ((obj), CLUTTER_TYPE_ACTOR_META, ClutterActorMetaClass))
+
+typedef struct _ClutterActorMetaPrivate         ClutterActorMetaPrivate;
+typedef struct _ClutterActorMetaClass           ClutterActorMetaClass;
+
+/**
+ * ClutterActorMeta:
+ *
+ * The <structname>ClutterActorMeta</structname> structure contains only
+ * private data and should be accessed using the provided API
+ *
+ * Since: 1.4
+ */
+struct _ClutterActorMeta
+{
+  /*< private >*/
+  GInitiallyUnowned parent_instance;
+
+  ClutterActorMetaPrivate *priv;
+};
+
+/**
+ * ClutterActorMetaClass:
+ * @set_actor: virtual function, invoked when attaching and detaching
+ *   a #ClutterActorMeta instance to a #ClutterActor
+ *
+ * The <structname>ClutterActorMetaClass</structname> structure contains
+ * only private data
+ *
+ * Since: 1.4
+ */
+struct _ClutterActorMetaClass
+{
+  /*< private >*/
+  GInitiallyUnownedClass parent_class;
+
+  /*< public >*/
+  void (* set_actor) (ClutterActorMeta *meta,
+                      ClutterActor     *actor);
+
+  /*< private >*/
+  void (* _clutter_meta1) (void);
+  void (* _clutter_meta2) (void);
+  void (* _clutter_meta3) (void);
+  void (* _clutter_meta4) (void);
+  void (* _clutter_meta5) (void);
+  void (* _clutter_meta6) (void);
+  void (* _clutter_meta7) (void);
+};
+
+GType clutter_actor_meta_get_type (void) G_GNUC_CONST;
+
+void                  clutter_actor_meta_set_name    (ClutterActorMeta *meta,
+                                                      const gchar      *name);
+G_CONST_RETURN gchar *clutter_actor_meta_get_name    (ClutterActorMeta *meta);
+void                  clutter_actor_meta_set_enabled (ClutterActorMeta *meta,
+                                                      gboolean          is_enabled);
+gboolean              clutter_actor_meta_get_enabled (ClutterActorMeta *meta);
+
+ClutterActor *        clutter_actor_meta_get_actor   (ClutterActorMeta *meta);
+
+/* private */
+void                 _clutter_actor_meta_set_actor   (ClutterActorMeta *meta,
+                                                      ClutterActor     *actor);
+
+G_END_DECLS
+
+#endif /* __CLUTTER_ACTOR_META_H__ */

clutter/clutter-types.h

@@ -40,12 +40,16 @@ G_BEGIN_DECLS
 
 /* Forward delarations to avoid header catch 22's */
 typedef struct _ClutterActor            ClutterActor;
+
 typedef struct _ClutterStage            ClutterStage;
 typedef struct _ClutterContainer        ClutterContainer; /* dummy */
 typedef struct _ClutterChildMeta        ClutterChildMeta;
 typedef struct _ClutterLayoutMeta       ClutterLayoutMeta;
+
 typedef struct _ClutterAnimator         ClutterAnimator;
 
+typedef struct _ClutterActorMeta        ClutterActorMeta;
+
 typedef union _ClutterEvent             ClutterEvent;
 
 /**

clutter/clutter.h

@@ -31,6 +31,7 @@
 #include "clutter-deprecated.h"
 
 #include "clutter-actor.h"
+#include "clutter-actor-meta.h"
 #include "clutter-alpha.h"
 #include "clutter-animatable.h"
 #include "clutter-animation.h"