Added GdkRGBA properties to GtkTextTag.

This now allows text view to render text with alpha values in
the text foreground and backgrounds, the work is almost complete,
currently the error-underline-color is still a GdkColor style property
and since we use only GdkRGBA for rendering it needs to be converted
and applied, probably a new rgba version of the style property should
also be introduced.

This commit adds tests/testtextview that must be run from the tests/
directory to show translucent text in action.

1 files changed, 26 insertions, 2 deletions

diff --git a/gtk/gtktextlayout.c b/gtk/gtktextlayout.c
index 35809873d5..f19ab618d2 100644
--- a/gtk/gtktextlayout.c
+++ b/gtk/gtktextlayout.c
@@ -1424,9 +1424,27 @@ gtk_text_attr_appearance_destroy (PangoAttribute *attr)
 {
   GtkTextAttrAppearance *appearance_attr = (GtkTextAttrAppearance *)attr;
 
+  if (appearance_attr->appearance.rgba[0])
+    gdk_rgba_free (appearance_attr->appearance.rgba[0]);
+
+  if (appearance_attr->appearance.rgba[1])
+    gdk_rgba_free (appearance_attr->appearance.rgba[1]);
+
   g_slice_free (GtkTextAttrAppearance, appearance_attr);
 }
 
+static gboolean 
+rgba_equal (const GdkRGBA *rgba1, const GdkRGBA *rgba2)
+{
+  if (rgba1 && rgba2)
+    return gdk_rgba_equal (rgba1, rgba2);
+  
+  if (rgba1 || rgba2)
+    return FALSE;
+
+  return TRUE;
+}
+
 static gboolean
 gtk_text_attr_appearance_compare (const PangoAttribute *attr1,
                                   const PangoAttribute *attr2)
@@ -1434,8 +1452,8 @@ gtk_text_attr_appearance_compare (const PangoAttribute *attr1,
   const GtkTextAppearance *appearance1 = &((const GtkTextAttrAppearance *)attr1)->appearance;
   const GtkTextAppearance *appearance2 = &((const GtkTextAttrAppearance *)attr2)->appearance;
 
-  return (gdk_color_equal (&appearance1->fg_color, &appearance2->fg_color) &&
-          gdk_color_equal (&appearance1->bg_color, &appearance2->bg_color) &&
+  return (rgba_equal (appearance1->rgba[0], appearance2->rgba[0]) &&
+          rgba_equal (appearance1->rgba[1], appearance2->rgba[1]) &&
           appearance1->underline == appearance2->underline &&
           appearance1->strikethrough == appearance2->strikethrough &&
           appearance1->draw_bg == appearance2->draw_bg);
@@ -1472,6 +1490,12 @@ gtk_text_attr_appearance_new (const GtkTextAppearance *appearance)
 
   result->appearance = *appearance;
 
+  if (appearance->rgba[0])
+    result->appearance.rgba[0] = gdk_rgba_copy (appearance->rgba[0]);
+
+  if (appearance->rgba[1])
+    result->appearance.rgba[1] = gdk_rgba_copy (appearance->rgba[1]);
+
   return (PangoAttribute *)result;
 }