[gnome-photos/wip/rishi/imageview: 5/9] Add PhotosImageContainer to animate changes to a GeglNode

[Debarshi Ray <debarshir src gnome org>]

commit e418b4fe04090b7e643f5a4895a5d555ba19a958
Author: Debarshi Ray <debarshir gnome org>
Date:   Sun Jan 31 19:06:46 2016 +0100

    Add PhotosImageContainer to animate changes to a GeglNode

 src/Makefile.am              |    2 +
 src/photos-image-container.c |  331 ++++++++++++++++++++++++++++++++++++++++++
 src/photos-image-container.h |   66 +++++++++
 3 files changed, 399 insertions(+), 0 deletions(-)
---
diff --git a/src/Makefile.am b/src/Makefile.am
index 9fbb3ff..a44095e 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -93,6 +93,8 @@ gnome_photos_SOURCES = \
        photos-header-bar.c \
        photos-header-bar.h \
        photos-icons.h \
+       photos-image-container.c \
+       photos-image-container.h \
        photos-image-view.c \
        photos-image-view.h \
        photos-indexing-notification.c \
diff --git a/src/photos-image-container.c b/src/photos-image-container.c
new file mode 100644
index 0000000..45cc1ce
--- /dev/null
+++ b/src/photos-image-container.c
@@ -0,0 +1,331 @@
+/*
+ * Photos - access, organize and share your photos on GNOME
+ * Copyright © 2016 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#include "config.h"
+
+#include <babl/babl.h>
+#include <cairo-gobject.h>
+#include <glib.h>
+
+#include "photos-image-container.h"
+#include "photos-image-view.h"
+#include "photos-utils.h"
+
+
+struct _PhotosImageContainer
+{
+  GtkBin parent_instance;
+  GeglNode *buffer_source;
+  GeglNode *graph;
+  GeglNode *node;
+  GtkWidget *stack;
+  GtkWidget *view;
+  cairo_region_t *bbox_region;
+  cairo_region_t *region;
+};
+
+struct _PhotosImageContainerClass
+{
+  GtkBinClass parent_class;
+};
+
+enum
+{
+  PROP_0,
+  PROP_NODE,
+  PROP_VIEW
+};
+
+
+G_DEFINE_TYPE (PhotosImageContainer, photos_image_container, GTK_TYPE_BIN);
+
+
+static void photos_image_container_computed (PhotosImageContainer *self, GeglRectangle *rect);
+
+
+static void
+photos_image_container_notify_transition_running (GtkStack *stack, GParamSpec *pspec, gpointer user_data)
+{
+  GtkWidget *view = GTK_WIDGET (user_data);
+
+  if (!gtk_stack_get_transition_running (stack))
+    gtk_widget_destroy (view);
+
+  g_signal_handlers_disconnect_by_func (stack, photos_image_container_notify_transition_running, view);
+}
+
+
+static gboolean
+photos_image_container_computed_idle (gpointer user_data)
+{
+  PhotosImageContainer *self = PHOTOS_IMAGE_CONTAINER (user_data);
+  const Babl *format;
+  GeglBuffer *buffer;
+  GeglBuffer *buffer_orig;
+  GtkWidget *view;
+
+  g_return_val_if_fail (self->buffer_source != NULL, G_SOURCE_REMOVE);
+
+  view = photos_image_view_new ();
+  photos_image_view_set_node (PHOTOS_IMAGE_VIEW (view), self->buffer_source);
+  gtk_container_add (GTK_CONTAINER (self->stack), view);
+  gtk_widget_show (view);
+  gtk_stack_set_visible_child (GTK_STACK (self->stack), view);
+
+  g_clear_object (&self->graph);
+  g_signal_handlers_block_by_func (self->node, photos_image_container_computed, self);
+
+  format = babl_format ("cairo-ARGB32");
+  buffer_orig = photos_utils_create_buffer_from_node (self->node, format);
+  buffer = gegl_buffer_dup (buffer_orig);
+  self->graph = gegl_node_new ();
+  self->buffer_source = gegl_node_new_child (self->graph,
+                                             "operation", "gegl:buffer-source",
+                                             "buffer", buffer,
+                                             NULL);
+  gegl_node_process (self->buffer_source);
+  photos_image_view_set_node (PHOTOS_IMAGE_VIEW (self->view), self->buffer_source);
+  gtk_stack_set_visible_child_full (GTK_STACK (self->stack), "view", GTK_STACK_TRANSITION_TYPE_CROSSFADE);
+  g_signal_connect (self->stack,
+                    "notify::transition-running",
+                    G_CALLBACK (photos_image_container_notify_transition_running),
+                    view);
+
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+  g_signal_handlers_unblock_by_func (self->node, photos_image_container_computed, self);
+
+  g_object_unref (buffer);
+  g_object_unref (buffer_orig);
+  return G_SOURCE_REMOVE;
+}
+
+
+static void
+photos_image_container_computed (PhotosImageContainer *self, GeglRectangle *rect)
+{
+  cairo_status_t status;
+
+  status = cairo_region_union_rectangle (self->region, (cairo_rectangle_int_t *) rect);
+  g_assert_cmpint (status, ==, CAIRO_STATUS_SUCCESS);
+
+  if (cairo_region_equal (self->bbox_region, self->region))
+    g_idle_add (photos_image_container_computed_idle, self);
+}
+
+
+static void
+photos_image_container_dispose (GObject *object)
+{
+  PhotosImageContainer *self = PHOTOS_IMAGE_CONTAINER (object);
+
+  g_clear_object (&self->graph);
+  g_clear_object (&self->node);
+
+  G_OBJECT_CLASS (photos_image_container_parent_class)->dispose (object);
+}
+
+
+static void
+photos_image_container_finalize (GObject *object)
+{
+  PhotosImageContainer *self = PHOTOS_IMAGE_CONTAINER (object);
+
+  g_clear_pointer (&self->bbox_region, (GDestroyNotify) cairo_region_destroy);
+  g_clear_pointer (&self->region, (GDestroyNotify) cairo_region_destroy);
+
+  G_OBJECT_CLASS (photos_image_container_parent_class)->finalize (object);
+}
+
+
+static void
+photos_image_container_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+{
+  PhotosImageContainer *self = PHOTOS_IMAGE_CONTAINER (object);
+
+  switch (prop_id)
+    {
+    case PROP_NODE:
+      g_value_set_object (value, self->node);
+      break;
+
+    case PROP_VIEW:
+      g_value_set_object (value, self->view);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+
+static void
+photos_image_container_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+{
+  PhotosImageContainer *self = PHOTOS_IMAGE_CONTAINER (object);
+
+  switch (prop_id)
+    {
+    case PROP_NODE:
+      {
+        GeglNode *node;
+
+        node = GEGL_NODE (g_value_get_object (value));
+        photos_image_container_set_node (self, node);
+        break;
+      }
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+
+static void
+photos_image_container_init (PhotosImageContainer *self)
+{
+  GtkStyleContext *context;
+  GtkWidget *sw;
+
+  self->stack = gtk_stack_new ();
+  gtk_widget_set_hexpand (self->stack, TRUE);
+  gtk_widget_set_vexpand (self->stack, TRUE);
+  gtk_container_add (GTK_CONTAINER (self), self->stack);
+
+  sw = gtk_scrolled_window_new (NULL, NULL);
+  gtk_scrolled_window_set_shadow_type (GTK_SCROLLED_WINDOW (sw), GTK_SHADOW_IN);
+  context = gtk_widget_get_style_context (sw);
+  gtk_style_context_add_class (context, "documents-scrolledwin");
+  gtk_stack_add_named (GTK_STACK (self->stack), sw, "view");
+
+  self->view = photos_image_view_new ();
+  gtk_container_add (GTK_CONTAINER (sw), self->view);
+
+  gtk_widget_show_all (sw);
+  gtk_stack_set_visible_child (GTK_STACK (self->stack), sw);
+}
+
+
+static void
+photos_image_container_class_init (PhotosImageContainerClass *class)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (class);
+
+  object_class->dispose = photos_image_container_dispose;
+  object_class->finalize = photos_image_container_finalize;
+  object_class->get_property = photos_image_container_get_property;
+  object_class->set_property = photos_image_container_set_property;
+
+  g_object_class_install_property (object_class,
+                                   PROP_NODE,
+                                   g_param_spec_object ("node",
+                                                        "GeglNode object",
+                                                        "The GeglNode to render",
+                                                        GEGL_TYPE_NODE,
+                                                        G_PARAM_CONSTRUCT | G_PARAM_READWRITE));
+
+  g_object_class_install_property (object_class,
+                                   PROP_VIEW,
+                                   g_param_spec_object ("view",
+                                                        "GtkWidget object",
+                                                        "The view inside this container",
+                                                        GTK_TYPE_WIDGET,
+                                                        G_PARAM_READABLE));
+}
+
+
+GtkWidget *
+photos_image_container_new (void)
+{
+  return g_object_new (PHOTOS_TYPE_IMAGE_CONTAINER, NULL);
+}
+
+
+GeglNode *
+photos_image_container_get_node (PhotosImageContainer *self)
+{
+  g_return_val_if_fail (PHOTOS_IS_IMAGE_CONTAINER (self), NULL);
+  return self->node;
+}
+
+
+GtkWidget *
+photos_image_container_get_view (PhotosImageContainer *self)
+{
+  g_return_val_if_fail (PHOTOS_IS_IMAGE_CONTAINER (self), NULL);
+  return self->view;
+}
+
+
+void
+photos_image_container_set_node (PhotosImageContainer *self, GeglNode *node)
+{
+  g_return_if_fail (PHOTOS_IS_IMAGE_CONTAINER (self));
+
+  if (self->node == node)
+    return;
+
+  if (self->node != NULL)
+    g_signal_handlers_disconnect_by_func (self->node, photos_image_container_computed, self);
+
+  self->buffer_source = NULL;
+  g_clear_object (&self->graph);
+  g_clear_object (&self->node);
+  g_clear_pointer (&self->bbox_region, (GDestroyNotify) cairo_region_destroy);
+  g_clear_pointer (&self->region, (GDestroyNotify) cairo_region_destroy);
+
+  if (node != NULL)
+    {
+      const Babl *format;
+      GeglBuffer *buffer;
+      GeglBuffer *buffer_orig;
+      GeglRectangle bbox;
+
+      g_object_ref (node);
+
+      bbox = gegl_node_get_bounding_box (node);
+      self->bbox_region = cairo_region_create_rectangle ((cairo_rectangle_int_t *) &bbox);
+      self->region = cairo_region_create ();
+
+      format = babl_format ("cairo-ARGB32");
+      buffer_orig = photos_utils_create_buffer_from_node (node, format);
+      buffer = gegl_buffer_dup (buffer_orig);
+      self->graph = gegl_node_new ();
+      self->buffer_source = gegl_node_new_child (self->graph,
+                                                 "operation", "gegl:buffer-source",
+                                                 "buffer", buffer,
+                                                 NULL);
+      gegl_node_process (self->buffer_source);
+
+      g_signal_connect_object (node,
+                               "computed",
+                               G_CALLBACK (photos_image_container_computed),
+                               self,
+                               G_CONNECT_SWAPPED);
+
+      g_object_unref (buffer);
+      g_object_unref (buffer_orig);
+    }
+
+  self->node = node;
+  photos_image_view_set_node (PHOTOS_IMAGE_VIEW (self->view), self->buffer_source);
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
diff --git a/src/photos-image-container.h b/src/photos-image-container.h
new file mode 100644
index 0000000..1db6173
--- /dev/null
+++ b/src/photos-image-container.h
@@ -0,0 +1,66 @@
+/*
+ * Photos - access, organize and share your photos on GNOME
+ * Copyright © 2016 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#ifndef PHOTOS_IMAGE_CONTAINER_H
+#define PHOTOS_IMAGE_CONTAINER_H
+
+#include <gegl.h>
+#include <gtk/gtk.h>
+
+G_BEGIN_DECLS
+
+#define PHOTOS_TYPE_IMAGE_CONTAINER (photos_image_container_get_type ())
+
+#define PHOTOS_IMAGE_CONTAINER(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST ((obj), \
+   PHOTOS_TYPE_IMAGE_CONTAINER, PhotosImageContainer))
+
+#define PHOTOS_IMAGE_CONTAINER_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST ((klass), \
+   PHOTOS_TYPE_IMAGE_CONTAINER, PhotosImageContainerClass))
+
+#define PHOTOS_IS_IMAGE_CONTAINER(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE ((obj), \
+   PHOTOS_TYPE_IMAGE_CONTAINER))
+
+#define PHOTOS_IS_IMAGE_CONTAINER_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE ((klass), \
+   PHOTOS_TYPE_IMAGE_CONTAINER))
+
+#define PHOTOS_IMAGE_CONTAINER_GET_CLASS(obj) \
+  (G_TYPE_INSTANCE_GET_CLASS ((obj), \
+   PHOTOS_TYPE_IMAGE_CONTAINER, PhotosImageContainerClass))
+
+typedef struct _PhotosImageContainer      PhotosImageContainer;
+typedef struct _PhotosImageContainerClass PhotosImageContainerClass;
+
+GType               photos_image_container_get_type           (void) G_GNUC_CONST;
+
+GtkWidget          *photos_image_container_new                (void);
+
+GeglNode           *photos_image_container_get_node           (PhotosImageContainer *self);
+
+GtkWidget          *photos_image_container_get_view           (PhotosImageContainer *self);
+
+void                photos_image_container_set_node           (PhotosImageContainer *self, GeglNode *node);
+
+G_END_DECLS
+
+#endif /* PHOTOS_IMAGE_CONTAINER_H */