[libchamplain] ChamplainPoint: Implement ChamplainExportable interface

[Jonas Danielsson <jonasdn src gnome org>]

commit c8829c4f86569fe5c75dc96d3578e29edbb327bd
Author: Jonas Danielsson <jonas threetimestwo org>
Date:   Sat Jan 9 10:35:50 2016 +0100

    ChamplainPoint: Implement ChamplainExportable interface

 champlain/champlain-point.c |   64 ++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 63 insertions(+), 1 deletions(-)
---
diff --git a/champlain/champlain-point.c b/champlain/champlain-point.c
index 06d10ad..c878724 100644
--- a/champlain/champlain-point.c
+++ b/champlain/champlain-point.c
@@ -55,6 +55,7 @@ enum
   PROP_0,
   PROP_COLOR,
   PROP_SIZE,
+  PROP_SURFACE,
 };
 
 /* static guint champlain_point_signals[LAST_SIGNAL] = { 0, }; */
@@ -64,11 +65,19 @@ struct _ChamplainPointPrivate
   ClutterColor *color;
   gdouble size;
   ClutterContent *canvas;
+  cairo_surface_t *surface;
 
   guint redraw_id;
 };
 
-G_DEFINE_TYPE (ChamplainPoint, champlain_point, CHAMPLAIN_TYPE_MARKER);
+static void set_surface (ChamplainExportable *exportable,
+    cairo_surface_t *surface);
+static cairo_surface_t *get_surface (ChamplainExportable *exportable);
+
+static void exportable_interface_init (ChamplainExportableIface *iface);
+
+G_DEFINE_TYPE_WITH_CODE (ChamplainPoint, champlain_point, CHAMPLAIN_TYPE_MARKER,
+    G_IMPLEMENT_INTERFACE (CHAMPLAIN_TYPE_EXPORTABLE, exportable_interface_init));
 
 #define GET_PRIVATE(obj) \
   (G_TYPE_INSTANCE_GET_PRIVATE ((obj), CHAMPLAIN_TYPE_POINT, ChamplainPointPrivate))
@@ -92,6 +101,10 @@ champlain_point_get_property (GObject *object,
       g_value_set_double (value, priv->size);
       break;
 
+    case PROP_SURFACE:
+      g_value_set_boxed (value, get_surface (CHAMPLAIN_EXPORTABLE (object)));
+      break;
+
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
     }
@@ -116,6 +129,10 @@ champlain_point_set_property (GObject *object,
       champlain_point_set_size (point, g_value_get_double (value));
       break;
 
+    case PROP_SURFACE:
+      set_surface (CHAMPLAIN_EXPORTABLE (object), g_value_get_boxed (value));
+      break;
+
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
     }
@@ -146,6 +163,10 @@ pick (ClutterActor *self,
 static void
 champlain_point_dispose (GObject *object)
 {
+  ChamplainPointPrivate *priv = CHAMPLAIN_POINT (object)->priv;
+
+  g_clear_pointer (&priv->surface, cairo_surface_destroy);
+
   G_OBJECT_CLASS (champlain_point_parent_class)->dispose (object);
 }
 
@@ -201,6 +222,11 @@ champlain_point_class_init (ChamplainPointClass *klass)
           G_MAXDOUBLE,
           12, 
           CHAMPLAIN_PARAM_READWRITE));
+
+  g_object_class_override_property (object_class,
+      PROP_SURFACE,
+      "surface");
+
 }
 
 
@@ -216,6 +242,8 @@ draw (ClutterCanvas *canvas,
   gdouble radius = size / 2.0;
   const ClutterColor *color;
 
+  set_surface (CHAMPLAIN_EXPORTABLE (point), cairo_get_target (cr));
+
   cairo_set_operator (cr, CAIRO_OPERATOR_CLEAR);
   cairo_paint (cr);
   cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
@@ -270,6 +298,40 @@ champlain_point_init (ChamplainPoint *point)
 }
 
 
+static void
+set_surface (ChamplainExportable *exportable,
+     cairo_surface_t *surface)
+{
+  g_return_if_fail (CHAMPLAIN_POINT (exportable));
+  g_return_if_fail (surface != NULL);
+
+  ChamplainPoint *self = CHAMPLAIN_POINT (exportable);
+
+  if (self->priv->surface == surface)
+    return;
+
+  cairo_surface_destroy (self->priv->surface);
+  self->priv->surface = cairo_surface_reference (surface);
+  g_object_notify (G_OBJECT (self), "surface");
+}
+
+static cairo_surface_t *
+get_surface (ChamplainExportable *exportable)
+{
+  g_return_val_if_fail (CHAMPLAIN_POINT (exportable), NULL);
+
+  return CHAMPLAIN_POINT (exportable)->priv->surface;
+}
+
+
+static void
+exportable_interface_init (ChamplainExportableIface *iface)
+{
+  iface->get_surface = get_surface;
+  iface->set_surface = set_surface;
+}
+
+
 /**
  * champlain_point_new:
  *