Add a rectangle actor with rounded corners

This is a ClutterCairoTexture subclass and uses Cairo for
drawing as Cairo is antialiased while Cogl is not.

https://bugzilla.gnome.org/show_bug.cgi?id=656576

1 files changed, 133 insertions, 0 deletions

diff --git a/src/empathy-rounded-rectangle.c b/src/empathy-rounded-rectangle.c
new file mode 100644
index 000000000..e06889d58
--- /dev/null
+++ b/src/empathy-rounded-rectangle.c
@@ -0,0 +1,133 @@
+/*
+ * empathy-rounded-rectangle.c - Source for EmpathyRoundedRectangle
+ * Copyright (C) 2011 Collabora Ltd.
+ * @author Emilio Pozuelo Monfort <emilio.pozuelo@collabora.co.uk>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <math.h>
+
+#include <clutter/clutter.h>
+
+#include "empathy-rounded-rectangle.h"
+
+G_DEFINE_TYPE (EmpathyRoundedRectangle,
+    empathy_rounded_rectangle,
+    CLUTTER_TYPE_CAIRO_TEXTURE)
+
+struct _EmpathyRoundedRectanglePriv
+{
+  ClutterColor border_color;
+  guint border_width;
+};
+
+static void
+empathy_rounded_rectangle_paint (EmpathyRoundedRectangle *self)
+{
+  guint width, height;
+  guint tmp_alpha;
+  cairo_t *cr;
+
+#define RADIUS (height / 8.)
+
+  clutter_cairo_texture_get_surface_size (CLUTTER_CAIRO_TEXTURE (self),
+      &width, &height);
+
+  /* compute the composited opacity of the actor taking into
+   * account the opacity of the color set by the user */
+  tmp_alpha = clutter_actor_get_paint_opacity (CLUTTER_ACTOR (self))
+            * self->priv->border_color.alpha
+            / 255;
+
+  cr = clutter_cairo_texture_create (CLUTTER_CAIRO_TEXTURE (self));
+
+  cairo_set_source_rgba (cr,
+      self->priv->border_color.red,
+      self->priv->border_color.green,
+      self->priv->border_color.blue,
+      tmp_alpha);
+
+  cairo_set_line_width (cr, self->priv->border_width);
+
+  cairo_set_operator (cr, CAIRO_OPERATOR_CLEAR);
+  cairo_paint (cr);
+  cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
+
+  cairo_new_sub_path (cr);
+  cairo_arc (cr, width - RADIUS, RADIUS, RADIUS,
+      -M_PI/2.0, 0);
+  cairo_arc (cr, width - RADIUS, height - RADIUS, RADIUS,
+      0, M_PI/2.0);
+  cairo_arc (cr, RADIUS, height - RADIUS, RADIUS,
+      M_PI/2.0, M_PI);
+  cairo_arc (cr, RADIUS, RADIUS, RADIUS,
+      M_PI, -M_PI/2.0);
+  cairo_close_path (cr);
+
+  cairo_stroke (cr);
+  cairo_destroy (cr);
+
+#undef RADIUS
+}
+
+static void
+empathy_rounded_rectangle_init (EmpathyRoundedRectangle *self)
+{
+  self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self,
+      EMPATHY_TYPE_ROUNDED_RECTANGLE, EmpathyRoundedRectanglePriv);
+
+  self->priv->border_width = 1;
+}
+
+static void
+empathy_rounded_rectangle_class_init (EmpathyRoundedRectangleClass *klass)
+{
+  g_type_class_add_private (klass, sizeof (EmpathyRoundedRectanglePriv));
+}
+
+ClutterActor *
+empathy_rounded_rectangle_new (guint width,
+    guint height)
+{
+  ClutterActor *self;
+
+  self = CLUTTER_ACTOR (g_object_new (EMPATHY_TYPE_ROUNDED_RECTANGLE, NULL));
+
+  clutter_cairo_texture_set_surface_size (CLUTTER_CAIRO_TEXTURE (self),
+      width, height);
+
+  empathy_rounded_rectangle_paint (EMPATHY_ROUNDED_RECTANGLE (self));
+
+  return self;
+}
+
+void
+empathy_rounded_rectangle_set_border_width (EmpathyRoundedRectangle *self,
+    guint border_width)
+{
+  self->priv->border_width = border_width;
+
+  empathy_rounded_rectangle_paint (self);
+}
+
+void
+empathy_rounded_rectangle_set_border_color (EmpathyRoundedRectangle *self,
+    const ClutterColor *color)
+{
+  self->priv->border_color = *color;
+
+  empathy_rounded_rectangle_paint (self);
+}