[gnome-shell/wip/carlosg/pango-alpha: 3/3] st: Forward CSS foreground alpha as a PangoAttribute to text

[Carlos Garnacho <carlosg src gnome org>]

commit 73472ba6a708b76f72d8b7f21fc3298d025276f7
Author: Carlos Garnacho <carlosg gnome org>
Date:   Fri Mar 27 23:06:49 2020 +0100

    st: Forward CSS foreground alpha as a PangoAttribute to text
    
    Let the PangoRenderer handle this.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/2504

 src/st/st-private.c | 6 ++++++
 1 file changed, 6 insertions(+)
---
diff --git a/src/st/st-private.c b/src/st/st-private.c
index db18587c78..e75e10788b 100644
--- a/src/st/st-private.c
+++ b/src/st/st-private.c
@@ -132,6 +132,12 @@ _st_set_text_from_style (ClutterText *text,
                                           color.blue * 255);
   pango_attr_list_insert (attribs, foreground);
 
+  if (color.alpha != 255)
+    {
+      PangoAttribute *alpha = pango_attr_foreground_alpha_new (color.alpha * 255);
+      pango_attr_list_insert (attribs, alpha);
+    }
+
   decoration = st_theme_node_get_text_decoration (theme_node);
   if (decoration)
     {