[gimp] app: add arc slices to GimpCanvasHandle

[Michael Natterer <mitch src gnome org>]

commit 6ebc29818eff59714bfefb9d7e175a6c4ec3ebd8
Author: Michael Natterer <mitch gimp org>
Date:   Fri Sep 24 01:32:09 2010 +0200

    app: add arc slices to GimpCanvasHandle

 app/display/gimpcanvashandle.c |   73 ++++++++++++++++++++++++++++++++++++++--
 app/display/gimpcanvashandle.h |   19 ++++++----
 2 files changed, 81 insertions(+), 11 deletions(-)
---
diff --git a/app/display/gimpcanvashandle.c b/app/display/gimpcanvashandle.c
index 4f59d5e..534a91a 100644
--- a/app/display/gimpcanvashandle.c
+++ b/app/display/gimpcanvashandle.c
@@ -41,7 +41,9 @@ enum
   PROP_X,
   PROP_Y,
   PROP_WIDTH,
-  PROP_HEIGHT
+  PROP_HEIGHT,
+  PROP_START_ANGLE,
+  PROP_SLICE_ANGLE
 };
 
 
@@ -55,6 +57,8 @@ struct _GimpCanvasHandlePrivate
   gdouble         y;
   gint            width;
   gint            height;
+  gdouble         start_angle;
+  gdouble         slice_angle;;
 };
 
 #define GET_PRIVATE(handle) \
@@ -132,12 +136,26 @@ gimp_canvas_handle_class_init (GimpCanvasHandleClass *klass)
                                                      3, 1001, 7,
                                                      GIMP_PARAM_READWRITE));
 
+  g_object_class_install_property (object_class, PROP_START_ANGLE,
+                                   g_param_spec_double ("start-angle", NULL, NULL,
+                                                        -1000, 1000, 0,
+                                                        GIMP_PARAM_READWRITE));
+
+  g_object_class_install_property (object_class, PROP_SLICE_ANGLE,
+                                   g_param_spec_double ("slice-angle", NULL, NULL,
+                                                        -1000, 1000, 2 * G_PI,
+                                                        GIMP_PARAM_READWRITE));
+
   g_type_class_add_private (klass, sizeof (GimpCanvasHandlePrivate));
 }
 
 static void
 gimp_canvas_handle_init (GimpCanvasHandle *handle)
 {
+  GimpCanvasHandlePrivate *private = GET_PRIVATE (handle);
+
+  private->start_angle = 0.0;
+  private->slice_angle = 2.0 * G_PI;
 }
 
 static void
@@ -168,6 +186,12 @@ gimp_canvas_handle_set_property (GObject      *object,
     case PROP_HEIGHT:
       private->height = g_value_get_int (value);
       break;
+    case PROP_START_ANGLE:
+      private->start_angle = g_value_get_double (value);
+      break;
+    case PROP_SLICE_ANGLE:
+      private->slice_angle = g_value_get_double (value);
+      break;
 
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
@@ -203,6 +227,12 @@ gimp_canvas_handle_get_property (GObject    *object,
     case PROP_HEIGHT:
       g_value_set_int (value, private->height);
       break;
+    case PROP_START_ANGLE:
+      g_value_set_double (value, private->start_angle);
+      break;
+    case PROP_SLICE_ANGLE:
+      g_value_set_double (value, private->slice_angle);
+      break;
 
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
@@ -400,13 +430,37 @@ gimp_canvas_handle_draw (GimpCanvasItem   *item,
       break;
 
     case GIMP_HANDLE_CIRCLE:
-      cairo_arc (cr, x, y, private->width / 2, 0, 2 * G_PI);
+      if (private->slice_angle >= 0)
+        {
+          cairo_arc_negative (cr, x, y, private->width / 2,
+                              - private->start_angle,
+                              - private->start_angle - private->slice_angle);
+        }
+      else
+        {
+          cairo_arc (cr, x, y, private->width / 2,
+                     - private->start_angle,
+                     - private->start_angle - private->slice_angle);
+        }
 
       _gimp_canvas_item_stroke (item, shell, cr);
       break;
 
     case GIMP_HANDLE_FILLED_CIRCLE:
-      cairo_arc (cr, x, y, (gdouble) private->width / 2.0, 0, 2 * G_PI);
+      cairo_move_to (cr, x, y);
+
+      if (private->slice_angle >= 0)
+        {
+          cairo_arc_negative (cr, x, y, (gdouble) private->width / 2.0,
+                              - private->start_angle,
+                              - private->start_angle - private->slice_angle);
+        }
+      else
+        {
+          cairo_arc (cr, x, y, (gdouble) private->width / 2.0,
+                     - private->start_angle,
+                     - private->start_angle - private->slice_angle);
+        }
 
       _gimp_canvas_item_fill (item, shell, cr);
       break;
@@ -479,3 +533,16 @@ gimp_canvas_handle_new (GimpHandleType  type,
                        "height", height,
                        NULL);
 }
+
+void
+gimp_canvas_handle_set_angles (GimpCanvasHandle *handle,
+                               gdouble           start_angle,
+                               gdouble           slice_angle)
+{
+  g_return_if_fail (GIMP_IS_CANVAS_HANDLE (handle));
+
+  g_object_set (handle,
+                "start-angle", start_angle,
+                "slice-angle", slice_angle,
+                NULL);
+}
diff --git a/app/display/gimpcanvashandle.h b/app/display/gimpcanvashandle.h
index 3172168..1691c84 100644
--- a/app/display/gimpcanvashandle.h
+++ b/app/display/gimpcanvashandle.h
@@ -47,14 +47,17 @@ struct _GimpCanvasHandleClass
 };
 
 
-GType            gimp_canvas_handle_get_type (void) G_GNUC_CONST;
-
-GimpCanvasItem * gimp_canvas_handle_new      (GimpHandleType  type,
-                                              GtkAnchorType   anchor,
-                                              gdouble         x,
-                                              gdouble         y,
-                                              gint            width,
-                                              gint            height);
+GType            gimp_canvas_handle_get_type   (void) G_GNUC_CONST;
+
+GimpCanvasItem * gimp_canvas_handle_new        (GimpHandleType    type,
+                                                GtkAnchorType     anchor,
+                                                gdouble           x,
+                                                gdouble           y,
+                                                gint              width,
+                                                gint              height);
+void             gimp_canvas_handle_set_angles (GimpCanvasHandle *handle,
+                                                gdouble           start_handle,
+                                                gdouble           slice_handle);
 
 
 #endif /* __GIMP_CANVAS_HANDLE_H__ */