[gtk+] Handle transparent colors better in GtkStyle emulation

[Alexander Larsson <alexl src gnome org>]

commit 10423726709539724be0ea19bed76ba4331af774
Author: Alexander Larsson <alexl redhat com>
Date:   Thu Jun 28 21:30:24 2012 +0200

    Handle transparent colors better in GtkStyle emulation
    
    We can't expose colors with alpha in the GtkStyle colors, since
    GdkColor has no alpha. Currently we throw away alpha completely,
    which fails very badly for completely transparent backgrounds,
    which now is the default for most widgets, as it typically
    end up with black-on-black.
    
    We handle this by falling back on the default/previous colors for
    transparent colors. This is is simple and avoids complete failure.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=671437

 gtk/deprecated/gtkstyle.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gtk/deprecated/gtkstyle.c b/gtk/deprecated/gtkstyle.c
index 5266368..16e3ce4 100644
--- a/gtk/deprecated/gtkstyle.c
+++ b/gtk/deprecated/gtkstyle.c
@@ -673,7 +673,7 @@ set_color (GtkStyle        *style,
       break;
     }
 
-  if (color)
+  if (color && color->alpha > 0.01)
     {
       dest->pixel = 0;
       dest->red = CLAMP ((guint) (color->red * 65535), 0, 65535);