[goocanvas/new-api] 2010-06-30 Damon Chaplin <damon gnome org>

[Damon Chaplin <damon src gnome org>]

commit b27d6438d17384ea2b2276c08cc29a9b19416a7b
Author: Damon Chaplin <damon gnome org>
Date:   Wed Jun 30 15:42:25 2010 +0100

    2010-06-30  Damon Chaplin  <damon gnome org>
    
    	    * src/goocanvas.c (goo_canvas_update_items_using_style): new function
    	    to update items when they are using a shared style.
    
    	    * demo/demo.c: added "Change Style" button to test the above.

 ChangeLog       |    7 ++++++
 demo/demo.c     |   58 +++++++++++++++++++++++++++++++++++++++++++++++-------
 src/goocanvas.c |   46 +++++++++++++++++++++++++++++++++++++++++++
 src/goocanvas.h |    5 ++++
 4 files changed, 108 insertions(+), 8 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index b68dd22..a74450f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 2010-06-30  Damon Chaplin  <damon gnome org>
 
+	* src/goocanvas.c (goo_canvas_update_items_using_style): new function
+	to update items when they are using a shared style.
+
+	* demo/demo.c: added "Change Style" button to test the above.
+
+2010-06-30  Damon Chaplin  <damon gnome org>
+
 	* demo/scalability-demo.c: fixed the USE_PIXMAP test.
 
 2010-06-30  Damon Chaplin  <damon gnome org>
diff --git a/demo/demo.c b/demo/demo.c
index 0e55bcb..70879bb 100644
--- a/demo/demo.c
+++ b/demo/demo.c
@@ -22,6 +22,8 @@ static GooCanvasItem *ellipse2, *textitem;
 static gboolean dragging = FALSE;
 static double drag_x, drag_y;
 
+static GooCanvasStyle *diamond_style = NULL;
+
 static void setup_canvas (GooCanvas *canvas);
 GtkWidget *create_canvas_fifteen (void);
 GtkWidget *create_canvas_features (void);
@@ -196,6 +198,41 @@ change_bounds_clicked (GtkWidget *button, GooCanvas *canvas)
 
 
 static void
+change_style_clicked (GtkWidget *button, GooCanvas *canvas)
+{
+  static gint last_state = 0;
+
+  if (last_state == 0)
+    {
+      g_object_set (diamond_style,
+		    "line-width", 3.0,
+		    "stroke-color", "orange",
+		    NULL);
+      goo_canvas_update_items_using_style (canvas, diamond_style, TRUE);
+      last_state = 1;
+    }
+  else if (last_state == 1)
+    {
+      g_object_set (diamond_style,
+		    "line-width", 1.0,
+		    "stroke-color", "red",
+		    NULL);
+      goo_canvas_update_items_using_style (canvas, diamond_style, TRUE);
+      last_state = 2;
+    }
+  else
+    {
+      g_object_set (diamond_style,
+		    "stroke-color", "black",
+		    "line-width", 1.0,
+		    NULL);
+      goo_canvas_update_items_using_style (canvas, diamond_style, FALSE);
+      last_state = 0;
+    }
+}
+
+
+static void
 move_ellipse_clicked (GtkWidget *button, GooCanvas *canvas)
 {
   static int last_state = 0;
@@ -609,6 +646,13 @@ create_canvas_primitives ()
 			  G_CALLBACK (change_bounds_clicked),
 			  canvas);
 
+	w = gtk_button_new_with_label("Change Style");
+	gtk_box_pack_start (GTK_BOX (hbox), w, FALSE, FALSE, 0);
+	gtk_widget_show (w);
+	g_signal_connect (w, "clicked",
+			  G_CALLBACK (change_style_clicked),
+			  canvas);
+
 	hbox = gtk_hbox_new (FALSE, 4);
 	gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
 	gtk_widget_show (hbox);
@@ -988,7 +1032,6 @@ static void
 polish_diamond (GooCanvasItem *root)
 {
   GooCanvasItem *group, *item;
-  GooCanvasStyle *style;
   int i, j;
   double a, x1, y1, x2, y2;
 
@@ -996,10 +1039,10 @@ polish_diamond (GooCanvasItem *root)
   goo_canvas_item_translate (group, 270, 230);
   setup_item_signals (group);
 
-  style = g_object_new (GOO_TYPE_CANVAS_STYLE,
-			"line-width", 1.0,
-			"line-cap", CAIRO_LINE_CAP_ROUND,
-			NULL);
+  diamond_style = g_object_new (GOO_TYPE_CANVAS_STYLE,
+				"line-width", 1.0,
+				"line-cap", CAIRO_LINE_CAP_ROUND,
+				NULL);
 
   for (i = 0; i < VERTICES; i++) {
     a = 2.0 * M_PI * i / VERTICES;
@@ -1011,11 +1054,10 @@ polish_diamond (GooCanvasItem *root)
       x2 = RADIUS * cos (a);
       y2 = RADIUS * sin (a);
       item = goo_canvas_polyline_new_line (group, x1, y1, x2, y2, NULL);
-      goo_canvas_item_simple_set_style ((GooCanvasItemSimple*) item, style);
+      goo_canvas_item_simple_set_style ((GooCanvasItemSimple*) item,
+					diamond_style);
     }
   }
-
-  g_object_unref (style);
 }
 
 
diff --git a/src/goocanvas.c b/src/goocanvas.c
index 923ab55..759da94 100644
--- a/src/goocanvas.c
+++ b/src/goocanvas.c
@@ -4013,3 +4013,49 @@ goo_canvas_query_tooltip (GtkWidget  *widget,
   return GTK_WIDGET_CLASS (goo_canvas_parent_class)->query_tooltip (widget, x, y, keyboard_tip, tooltip);
 }
 
+
+static void
+goo_canvas_update_items_using_style_recurse (GooCanvasItem  *item,
+					     GooCanvasStyle *style,
+					     gboolean        recompute_bounds)
+{
+  GooCanvasItemSimple *simple = (GooCanvasItemSimple*) item;
+  gint n_children, i;
+
+  if (GOO_IS_CANVAS_ITEM_SIMPLE (item) && simple->style == style)
+    goo_canvas_item_simple_changed (simple, TRUE);
+
+  n_children = goo_canvas_item_get_n_children (item);
+  for (i = 0; i < n_children; i++)
+    {
+      GooCanvasItem *child = goo_canvas_item_get_child (item, i);
+      goo_canvas_update_items_using_style_recurse (child, style,
+						   recompute_bounds);
+    }
+}
+
+
+/**
+ * goo_canvas_update_items_using_style:
+ * @canvas: a #GooCanvas.
+ * @style: a #GooCanvasStyle.
+ * @recompute_bounds: %TRUE if the bounds of the items should be recomputed,
+ *  e.g. if the line width has been changed.
+ *
+ * Requests an update of all canvas items using the given style.
+ * This function must be called when many items are using a shared
+ * #GooCanvasStyle which has been changed.
+ **/
+void
+goo_canvas_update_items_using_style (GooCanvas      *canvas,
+				     GooCanvasStyle *style,
+				     gboolean        recompute_bounds)
+{
+  if (canvas->root_item)
+    goo_canvas_update_items_using_style_recurse (canvas->root_item,
+						 style, recompute_bounds);
+
+  if (canvas->static_root_item)
+    goo_canvas_update_items_using_style_recurse (canvas->static_root_item,
+						 style, recompute_bounds);
+}
diff --git a/src/goocanvas.h b/src/goocanvas.h
index a5d060f..7a9d48e 100644
--- a/src/goocanvas.h
+++ b/src/goocanvas.h
@@ -236,6 +236,11 @@ void            goo_canvas_render	    (GooCanvas		   *canvas,
 					     const GooCanvasBounds *bounds,
 					     gdouble                scale);
 
+void            goo_canvas_update_items_using_style (GooCanvas      *canvas,
+						     GooCanvasStyle *style,
+						     gboolean        recompute_bounds);
+
+
 /*
  * Coordinate conversion.
  */