[clutter/wip/actor-content: 14/25] Add ClutterContent

[Emmanuele Bassi <ebassi src gnome org>]

commit 63c7f1e7dd7fa52fe75a81fa0215e889318333ce
Author: Emmanuele Bassi <ebassi linux intel com>
Date:   Thu Nov 18 18:15:22 2010 +0000

    Add ClutterContent
    
    ClutterContent is an interface that provides a "paint object" API
    that can be used to abstract (and share) the painting logic of an
    actor.

 clutter/Makefile.am               |    3 +
 clutter/clutter-content-private.h |   20 +++
 clutter/clutter-content.c         |  330 +++++++++++++++++++++++++++++++++++++
 clutter/clutter-content.h         |   73 ++++++++
 clutter/clutter-types.h           |    2 +
 clutter/clutter.h                 |    1 +
 6 files changed, 429 insertions(+), 0 deletions(-)
---
diff --git a/clutter/Makefile.am b/clutter/Makefile.am
index 40328f3..f1d7fdb 100644
--- a/clutter/Makefile.am
+++ b/clutter/Makefile.am
@@ -101,6 +101,7 @@ source_h =					\
 	$(srcdir)/clutter-colorize-effect.h	\
 	$(srcdir)/clutter-constraint.h		\
 	$(srcdir)/clutter-container.h		\
+	$(srcdir)/clutter-content.h		\
 	$(srcdir)/clutter-deform-effect.h	\
 	$(srcdir)/clutter-deprecated.h		\
 	$(srcdir)/clutter-desaturate-effect.h	\
@@ -186,6 +187,7 @@ source_c = \
 	$(srcdir)/clutter-colorize-effect.c	\
 	$(srcdir)/clutter-constraint.c		\
 	$(srcdir)/clutter-container.c		\
+	$(srcdir)/clutter-content.c		\
 	$(srcdir)/clutter-deform-effect.c	\
 	$(srcdir)/clutter-desaturate-effect.c	\
 	$(srcdir)/clutter-device-manager.c	\
@@ -244,6 +246,7 @@ source_h_priv = \
 	$(srcdir)/clutter-actor-private.h		\
 	$(srcdir)/clutter-backend-private.h		\
 	$(srcdir)/clutter-bezier.h			\
+	$(srcdir)/clutter-content-private.h		\
 	$(srcdir)/clutter-debug.h 			\
 	$(srcdir)/clutter-device-manager-private.h	\
 	$(srcdir)/clutter-effect-private.h		\
diff --git a/clutter/clutter-content-private.h b/clutter/clutter-content-private.h
new file mode 100644
index 0000000..5afb026
--- /dev/null
+++ b/clutter/clutter-content-private.h
@@ -0,0 +1,20 @@
+#ifndef __CLUTTER_CONTENT_PRIVATE_H__
+#define __CLUTTER_CONTENT_PRIVATE_H__
+
+#include <clutter/clutter-content.h>
+
+G_BEGIN_DECLS
+
+void            _clutter_content_add_actor      (ClutterContent     *content,
+                                                 ClutterActor       *actor);
+void            _clutter_content_remove_actor   (ClutterContent     *content,
+                                                 ClutterActor       *actor);
+GHashTable *    _clutter_content_get_actors     (ClutterContent     *content);
+
+void            _clutter_content_pick_content   (ClutterContent     *content,
+                                                 ClutterActor       *actor,
+                                                 const ClutterColor *pick_color);
+
+G_END_DECLS
+
+#endif /* __CLUTTER_CONTENT_PRIVATE_H__ */
diff --git a/clutter/clutter-content.c b/clutter/clutter-content.c
new file mode 100644
index 0000000..342fee5
--- /dev/null
+++ b/clutter/clutter-content.c
@@ -0,0 +1,330 @@
+/**
+ * SECTION:clutter-content
+ * @Title: ClutterContent
+ * @Short_Description: Paint objects
+ *
+ * #ClutterContent is an interface implemented by objects that provide a way
+ * to paint a #ClutterActor.
+ *
+ * A #ClutterContent implementation should provide the geometry of the paint
+ * mask, and the actual changes to the pipeline's state.
+ *
+ * Each #ClutterActor can use a #ClutterContent implementation to paint
+ * itself; multiple #ClutterActor<!-- -->s can share the same #ClutterContent
+ * instance.
+ *
+ * #ClutterContent is available since Clutter 1.8.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "clutter-content-private.h"
+#include "clutter-private.h"
+
+#include "clutter-actor.h"
+
+/**
+ * ClutterContent:
+ *
+ * <structname>ClutterContent</structname> is an opaque structure whose
+ * members cannot be directly accessed.
+ *
+ * Since: 1.8
+ */
+
+static GQuark quark_content_actor = 0;
+
+/* for G_DEFINE_INTERFACE */
+typedef ClutterContentIface     ClutterContentInterface;
+
+G_DEFINE_INTERFACE (ClutterContent, clutter_content, G_TYPE_OBJECT);
+
+static void
+clutter_content_real_update_geometry (ClutterContent *content,
+                                      ClutterActor   *actor)
+{
+  ClutterActorBox allocation;
+
+  clutter_actor_get_allocation_box (actor, &allocation);
+
+  cogl_rectangle_with_texture_coords (clutter_actor_box_get_x (&allocation),
+                                      clutter_actor_box_get_y (&allocation),
+                                      clutter_actor_box_get_width (&allocation),
+                                      clutter_actor_box_get_height (&allocation),
+                                      0.0f, 0.0f,
+                                      1.0f, 1.0f);
+}
+
+static gboolean
+clutter_content_real_setup_material (ClutterContent *content,
+                                     ClutterActor   *actor)
+{
+  guint8 paint_opacity;
+
+  paint_opacity = clutter_actor_get_paint_opacity (actor);
+
+  cogl_set_source_color4f (0.0, 0.0, 0.0, paint_opacity / 255.0);
+
+  return TRUE;
+}
+
+static void
+clutter_content_real_paint_content (ClutterContent *content,
+                                    ClutterActor   *actor)
+{
+  if (!clutter_content_setup_material (content, actor))
+    return;
+
+  clutter_content_update_geometry (content, actor);
+}
+
+static gboolean
+clutter_content_real_get_paint_volume (ClutterContent     *content,
+                                       ClutterActor       *actor,
+                                       ClutterPaintVolume *volume)
+{
+  return TRUE;
+}
+
+static void
+clutter_content_real_invalidate (ClutterContent *content)
+{
+  GHashTable *actors = _clutter_content_get_actors (content);
+  GHashTableIter iter;
+  gpointer key, value;
+
+  if (actors == NULL)
+    return;
+
+  key = value = NULL;
+  g_hash_table_iter_init (&iter, actors);
+  while (g_hash_table_iter_next (&iter, &key, &value))
+    {
+      ClutterActor *actor = key;
+
+      g_assert (actor != NULL);
+
+      clutter_actor_queue_redraw (actor);
+    }
+}
+
+static void
+clutter_content_default_init (ClutterContentInterface *iface)
+{
+  quark_content_actor = g_quark_from_static_string ("clutter-content-actors");
+
+  iface->setup_material = clutter_content_real_setup_material;
+  iface->update_geometry = clutter_content_real_update_geometry;
+  iface->paint_content = clutter_content_real_paint_content;
+  iface->get_paint_volume = clutter_content_real_get_paint_volume;
+  iface->invalidate = clutter_content_real_invalidate;
+}
+
+/**
+ * clutter_content_setup_material:
+ * @content: a #ClutterContent
+ * @actor: a #ClutterActor
+ *
+ * Sets up the material for the given @actor.
+ *
+ * Return value: %TRUE if the material was set up correctly, and
+ *   the @content should be painted, and %FALSE otherwise.
+ *
+ * Since: 1.8
+ */
+gboolean
+clutter_content_setup_material (ClutterContent *content,
+                                ClutterActor   *actor)
+{
+  g_return_val_if_fail (CLUTTER_IS_CONTENT (content), FALSE);
+  g_return_val_if_fail (CLUTTER_IS_ACTOR (actor), FALSE);
+
+  return CLUTTER_CONTENT_GET_IFACE (content)->setup_material (content, actor);
+}
+
+/**
+ * clutter_content_update_geometry:
+ * @content: a #ClutterContent
+ * @actor: a #ClutterActor
+ *
+ * Updates the geometry for the given @actor.
+ *
+ * Since: 1.8
+ */
+void
+clutter_content_update_geometry (ClutterContent *content,
+                                 ClutterActor   *actor)
+{
+  g_return_if_fail (CLUTTER_IS_CONTENT (content));
+  g_return_if_fail (CLUTTER_IS_ACTOR (actor));
+
+  CLUTTER_CONTENT_GET_IFACE (content)->update_geometry (content, actor);
+}
+
+/**
+ * clutter_content_paint_content:
+ * @content: a #ClutterContent
+ * @actor: a #ClutterActor
+ *
+ * Updates the graphics pipeline for the given @actor.
+ *
+ * The default implementation for #ClutterContent will call
+ * clutter_content_setup_material() and, depending on the returned
+ * value, clutter_content_update_geometry(). Any #ClutterContent
+ * implementation might decide to override either of these virtual
+ * functions, or override the <function>paint_content</function>
+ * virtual function entirely.
+ *
+ * #ClutterActor will call clutter_content_paint_content() when
+ * painting.
+ *
+ * Since: 1.8
+ */
+void
+clutter_content_paint_content (ClutterContent *content,
+                               ClutterActor   *actor)
+{
+  g_return_if_fail (CLUTTER_IS_CONTENT (content));
+  g_return_if_fail (CLUTTER_IS_ACTOR (actor));
+
+  CLUTTER_CONTENT_GET_IFACE (content)->paint_content (content, actor);
+}
+
+/*< private >
+ * clutter_content_pick_content:
+ * @content: a #ClutterContent
+ * @actor: a #ClutterActor
+ * @pick_color: the color used to pick @actor
+ *
+ * Updates the graphics pipeline to paint the given @actor in pick
+ * mode, using the @content's geometry.
+ *
+ * This is an internal method called by the default pick implementation
+ * inside #ClutterActor.
+ *
+ * Since: 1.8
+ */
+void
+_clutter_content_pick_content (ClutterContent     *content,
+                               ClutterActor       *actor,
+                               const ClutterColor *pick_color)
+{
+  cogl_set_source_color4ub (pick_color->red,
+                            pick_color->green,
+                            pick_color->blue,
+                            pick_color->alpha);
+
+  clutter_content_update_geometry (content, actor);
+}
+
+/**
+ * clutter_content_get_paint_volume:
+ * @content: a #ClutterContent
+ * @actor: a #ClutterActor
+ * @volume: a #ClutterPaintVolume
+ *
+ * Asks @content to modify a #ClutterActor's paint volume, in case
+ * the #ClutterContent instance should paint outside the allocation
+ * of @actor.
+ *
+ * Return value: %TRUE if the paint volume is valid, and %FALSE if
+ *   it is invalid and should be discarded
+ *
+ * Since: 1.8
+ */
+gboolean
+clutter_content_get_paint_volume (ClutterContent     *content,
+                                  ClutterActor       *actor,
+                                  ClutterPaintVolume *volume)
+{
+  g_return_val_if_fail (CLUTTER_IS_CONTENT (content), FALSE);
+  g_return_val_if_fail (CLUTTER_IS_ACTOR (actor), FALSE);
+  g_return_val_if_fail (volume != NULL, FALSE);
+
+  return CLUTTER_CONTENT_GET_IFACE (content)->get_paint_volume (content,
+                                                                actor,
+                                                                volume);
+}
+
+/*< private >
+ * clutter_content_get_actors:
+ * @content: a #ClutterContent
+ *
+ * Retrieves a pointer to the list of #ClutterActor<!-- -->s using
+ * @content to paint themselves.
+ *
+ * Return value: a #GHashTable of #ClutterActor instances. The list is
+ *   owned by the #ClutterContent and it should not be freed
+ */
+GHashTable *
+_clutter_content_get_actors (ClutterContent *content)
+{
+  return g_object_get_qdata (G_OBJECT (content), quark_content_actor);
+}
+
+/*< private >
+ * clutter_content_remove_actor:
+ * @content: a #ClutterContent
+ * @actor: a #ClutterActor
+ *
+ * Removes @actor from the list of #ClutterActor<!-- -->s using @content
+ * to paint themselves.
+ */
+void
+_clutter_content_remove_actor (ClutterContent *content,
+                               ClutterActor   *actor)
+{
+  GHashTable *actors = _clutter_content_get_actors (content);
+
+  if (G_UNLIKELY (actors == NULL))
+    return;
+
+  g_hash_table_remove (actors, actor);
+}
+
+/*< private >
+ * clutter_content_add_actor:
+ * @content: a #ClutterContent
+ * @actor: a #ClutterActor
+ *
+ * Adds @actor to the list of #ClutterActor<!-- -->s using @content
+ * when painting themselves.
+ */
+void
+_clutter_content_add_actor (ClutterContent *content,
+                            ClutterActor   *actor)
+{
+  GHashTable *actors = _clutter_content_get_actors (content);
+
+  if (G_UNLIKELY (actors == NULL))
+    {
+      actors = g_hash_table_new (NULL, NULL);
+      g_object_set_qdata_full (G_OBJECT (content), quark_content_actor,
+                               actors,
+                               (GDestroyNotify) g_hash_table_destroy);
+    }
+
+  g_hash_table_insert (actors, actor, GUINT_TO_POINTER (1));
+}
+
+/**
+ * clutter_content_invalidate:
+ * @content: a #ClutterContent
+ *
+ * Invalidates a #ClutterContent and causes a redraw to be queued on
+ * every actor using @content.
+ *
+ * This function should only be called by #ClutterContent implementations
+ * that have parameters affecting the way they are painted.
+ *
+ * Since: 1.8
+ */
+void
+clutter_content_invalidate (ClutterContent *content)
+{
+  g_return_if_fail (CLUTTER_IS_CONTENT (content));
+
+  CLUTTER_CONTENT_GET_IFACE (content)->invalidate (content);
+}
diff --git a/clutter/clutter-content.h b/clutter/clutter-content.h
new file mode 100644
index 0000000..6d59ab5
--- /dev/null
+++ b/clutter/clutter-content.h
@@ -0,0 +1,73 @@
+#if !defined(__CLUTTER_H_INSIDE__) && !defined(CLUTTER_COMPILATION)
+#error "Only <clutter/clutter.h> can be included directly."
+#endif
+
+#ifndef __CLUTTER_CONTENT_H__
+#define __CLUTTER_CONTENT_H__
+
+#include <clutter/clutter-types.h>
+
+G_BEGIN_DECLS
+
+#define CLUTTER_TYPE_CONTENT            (clutter_content_get_type ())
+#define CLUTTER_CONTENT(obj)            (G_TYPE_CHECK_INSTANCE_CAST ((obj), CLUTTER_TYPE_CONTENT, ClutterContent))
+#define CLUTTER_IS_CONTENT(obj)         (G_TYPE_CHECK_INSTANCE_TYPE ((obj), CLUTTER_TYPE_CONTENT))
+#define CLUTTER_CONTENT_GET_IFACE(obj)  (G_TYPE_INSTANCE_GET_INTERFACE ((obj), CLUTTER_TYPE_CONTENT, ClutterContentIface))
+
+typedef struct _ClutterContentIface     ClutterContentIface;
+
+/**
+ * ClutterContentIface:
+ * @setup_material: virtual function, used to set up the material used
+ *   by the content
+ * @update_geometry: virtual function, used to update the geometry of the
+ *   content for the given actor
+ * @paint_content: virtual function, used to paint the content for
+ *   the given actor
+ * @get_paint_volume: virtual function, used to update the paint volume
+ *   for the given actor
+ * @invalidate: virtual function, used to notify actors of a content
+ *   update
+ *
+ * Interface for #ClutterActor contents.
+ *
+ * Since: 1.8
+ */
+struct _ClutterContentIface
+{
+  /*< private >*/
+  GTypeInterface g_iface;
+
+  /*< public >*/
+  gboolean (* setup_material)   (ClutterContent     *content,
+                                 ClutterActor       *actor);
+  void     (* update_geometry)  (ClutterContent     *content,
+                                 ClutterActor       *actor);
+  void     (* paint_content)    (ClutterContent     *content,
+                                 ClutterActor       *actor);
+
+  gboolean (* get_paint_volume) (ClutterContent     *content,
+                                 ClutterActor       *actor,
+                                 ClutterPaintVolume *volume);
+
+  void     (* invalidate)       (ClutterContent     *content);
+};
+
+GType clutter_content_get_type (void) G_GNUC_CONST;
+
+gboolean        clutter_content_setup_material          (ClutterContent     *content,
+                                                         ClutterActor       *actor);
+void            clutter_content_update_geometry         (ClutterContent     *content,
+                                                         ClutterActor       *actor);
+void            clutter_content_paint_content           (ClutterContent     *content,
+                                                         ClutterActor       *actor);
+
+gboolean        clutter_content_get_paint_volume        (ClutterContent     *content,
+                                                         ClutterActor       *actor,
+                                                         ClutterPaintVolume *volume);
+
+void            clutter_content_invalidate              (ClutterContent     *content);
+
+G_END_DECLS
+
+#endif /* __CLUTTER_CONTENT_H__ */
diff --git a/clutter/clutter-types.h b/clutter/clutter-types.h
index 8ad7261..f4de269 100644
--- a/clutter/clutter-types.h
+++ b/clutter/clutter-types.h
@@ -53,6 +53,8 @@ typedef struct _ClutterAction           ClutterAction;
 typedef struct _ClutterConstraint       ClutterConstraint;
 typedef struct _ClutterEffect           ClutterEffect;
 
+typedef struct _ClutterContent          ClutterContent; /* dummy */
+
 typedef struct _ClutterShader           ClutterShader;
 
 typedef struct _ClutterColor            ClutterColor;
diff --git a/clutter/clutter.h b/clutter/clutter.h
index 1baf56e..e5cebc3 100644
--- a/clutter/clutter.h
+++ b/clutter/clutter.h
@@ -63,6 +63,7 @@
 #include "clutter-colorize-effect.h"
 #include "clutter-constraint.h"
 #include "clutter-container.h"
+#include "clutter-content.h"
 #include "clutter-deform-effect.h"
 #include "clutter-desaturate-effect.h"
 #include "clutter-device-manager.h"