[gnome-shell] Implement radial gradients for StWidget

[Florian Müllner <fmuellner src gnome org>]

commit 59d6029f478aa5a12aded8a6ab69ad0d2c547dda
Author: Florian Müllner <fmuellner src gnome org>
Date:   Sun Jan 10 02:17:01 2010 +0100

    Implement radial gradients for StWidget
    
    Some theme authors have stated interest in radial gradient backgrounds.
    The w3c has some draft:
    
    http://dev.w3.org/csswg/css3-images/#radial-gradients
    
    As this is rather complex, we add only some very basic support, which
    extends our syntax for linear gradients:
    
    background-gradient-direction: [vertical|horizontal|radial]
    
    Gradients are centered circles, whose size is determined by the closest
    side.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=604945

 src/st/st-theme-node.c |    4 ++++
 src/st/st-theme-node.h |    3 ++-
 src/st/st-widget.c     |   10 +++++++++-
 3 files changed, 15 insertions(+), 2 deletions(-)
---
diff --git a/src/st/st-theme-node.c b/src/st/st-theme-node.c
index f8998e8..03d1543 100644
--- a/src/st/st-theme-node.c
+++ b/src/st/st-theme-node.c
@@ -1356,6 +1356,10 @@ ensure_background (StThemeNode *node)
             {
               node->background_gradient_type = ST_GRADIENT_HORIZONTAL;
             }
+          else if (strcmp (term->content.str->stryng->str, "radial") == 0)
+            {
+              node->background_gradient_type = ST_GRADIENT_RADIAL;
+            }
           else
             {
               g_warning ("Unrecognized background-gradient-direction \"%s\"",
diff --git a/src/st/st-theme-node.h b/src/st/st-theme-node.h
index 31fb08e..afb8f0f 100644
--- a/src/st/st-theme-node.h
+++ b/src/st/st-theme-node.h
@@ -61,7 +61,8 @@ typedef enum {
 typedef enum {
   ST_GRADIENT_NONE,
   ST_GRADIENT_VERTICAL,
-  ST_GRADIENT_HORIZONTAL
+  ST_GRADIENT_HORIZONTAL,
+  ST_GRADIENT_RADIAL
 } StGradientType;
 
 GType st_theme_node_get_type (void) G_GNUC_CONST;
diff --git a/src/st/st-widget.c b/src/st/st-widget.c
index e97d7cf..9759b72 100644
--- a/src/st/st-widget.c
+++ b/src/st/st-widget.c
@@ -632,8 +632,16 @@ st_widget_redraw_gradient (StWidget  *widget)
 
   if (priv->bg_gradient_type == ST_GRADIENT_VERTICAL)
     pattern = cairo_pattern_create_linear (0, 0, 0, height);
-  else
+  else if (priv->bg_gradient_type == ST_GRADIENT_HORIZONTAL)
     pattern = cairo_pattern_create_linear (0, 0, width, 0);
+  else
+    {
+      gdouble cx, cy;
+
+      cx = width / 2.;
+      cy = height / 2.;
+      pattern = cairo_pattern_create_radial (cx, cy, 0, cx, cy, MIN (cx, cy));
+    }
 
   cairo_pattern_add_color_stop_rgba (pattern, 0,
                                      start->red / 255.,