[gnote] Use RGBA for contrast

[Aurimas Černius <aurimasc src gnome org>]

commit be68da9998f5f9978ec83ee1e2356f80c92a8b72
Author: Aurimas Černius <aurisc4 gmail com>
Date:   Fri Jan 1 18:17:07 2021 +0200

    Use RGBA for contrast

 src/contrast.cpp | 17 +++++++++--------
 src/contrast.hpp |  7 ++++---
 src/notetag.cpp  | 13 +++++--------
 src/notetag.hpp  |  8 ++++----
 4 files changed, 22 insertions(+), 23 deletions(-)
---
diff --git a/src/contrast.cpp b/src/contrast.cpp
index 81167f64..53525ff3 100644
--- a/src/contrast.cpp
+++ b/src/contrast.cpp
@@ -1,6 +1,7 @@
 /*
  * contrast.c
  *
+ * Copyright (c) 2021  Aurimas Cernius
  * Copyright (c) 2006-2007  David Trowbridge
  *
  * Permission is hereby granted, free of charge, to any person obtaining
@@ -192,8 +193,8 @@ lab_distance(float La,
  * Creates a specific color value for a foreground color, optimizing for
  * maximum readability against the background.
  */
-Gdk::Color
-contrast_render_foreground_color(const Gdk::Color & background,
+Gdk::RGBA
+contrast_render_foreground_color(const Gdk::RGBA & background,
                                  ContrastPaletteColor color)
 {
   float L, a, b;
@@ -202,10 +203,9 @@ contrast_render_foreground_color(const Gdk::Color & background,
   float points[8][3];
   float ld, cd;
   int i;
-  Gdk::Color rcolor;
+  Gdk::RGBA rcolor;
 
-  rgb_to_lab(background.get_red(), background.get_green(), 
-             background.get_blue(), &L, &a, &b);
+  rgb_to_lab(background.get_red_u(), background.get_green_u(), background.get_blue_u(), &L, &a, &b);
 
   points[0][0] = color_regions[color][0]; points[0][1] = color_regions[color][2]; points[0][2] = 
color_regions[color][4];
   points[1][0] = color_regions[color][0]; points[1][1] = color_regions[color][2]; points[1][2] = 
color_regions[color][5];
@@ -254,9 +254,10 @@ contrast_render_foreground_color(const Gdk::Color & background,
 //             &rcolor.red,
 //             &rcolor.green,
 //             &rcolor.blue);
-  rcolor.set_red(re);
-  rcolor.set_green(gr);
-  rcolor.set_blue(bl);
+  rcolor.set_red_u(re);
+  rcolor.set_green_u(gr);
+  rcolor.set_blue_u(bl);
+  rcolor.set_alpha_u(65535);
 
   return rcolor;
 }
diff --git a/src/contrast.hpp b/src/contrast.hpp
index 26c49d8a..3ad2f6be 100644
--- a/src/contrast.hpp
+++ b/src/contrast.hpp
@@ -1,6 +1,7 @@
 /*
  * contrast.h
  *
+ * Copyright (c) 2021  Aurimas Cernius
  * Copyright (c) 2006-2007  David Trowbridge
  *
  * Permission is hereby granted, free of charge, to any person obtaining
@@ -27,7 +28,7 @@
 #ifndef __CONTRAST_H_
 #define __CONTRAST_H_
 
-#include <gdkmm/color.h>
+#include <gdkmm/rgba.h>
 
 /*
  * Defined colors.  Keep this list alphabetized if you add new ones, but set the
@@ -61,8 +62,8 @@ typedef enum {
   CONTRAST_COLOR_LAST        = 23
 } ContrastPaletteColor;
 
-Gdk::Color
-contrast_render_foreground_color(const Gdk::Color & background,
+Gdk::RGBA
+contrast_render_foreground_color(const Gdk::RGBA & background,
                                  ContrastPaletteColor color);
 
 #endif
diff --git a/src/notetag.cpp b/src/notetag.cpp
index 7f63804e..9a9b0784 100644
--- a/src/notetag.cpp
+++ b/src/notetag.cpp
@@ -1,7 +1,7 @@
 /*
  * gnote
  *
- * Copyright (C) 2011,2013-2014,2017,2019-2020 Aurimas Cernius
+ * Copyright (C) 2011,2013-2014,2017,2019-2021 Aurimas Cernius
  * Copyright (C) 2009 Hubert Figuiere
  *
  * This program is free software: you can redistribute it and/or modify
@@ -292,20 +292,17 @@ namespace gnote {
     }
   }
 
-  Gdk::Color NoteTag::get_background() const
+  Gdk::RGBA NoteTag::get_background() const
   {
     /* We can't know the exact background because we're not
        in TextView's rendering, but we can make a guess */
     if (property_background_set().get_value())
-      return property_background_gdk().get_value();
+      return property_background_rgba().get_value();
 
-    Gdk::RGBA rgba = Gtk::TextView().get_style_context()->get_background_color();
-    Gdk::Color color;
-    color.set_rgb(rgba.get_red_u(), rgba.get_green_u(), rgba.get_blue_u());
-    return color;
+    return Gtk::TextView().get_style_context()->get_background_color();
   }
 
-  Gdk::Color NoteTag::render_foreground(ContrastPaletteColor symbol)
+  Gdk::RGBA NoteTag::render_foreground(ContrastPaletteColor symbol)
   {
     return contrast_render_foreground_color(get_background(), symbol);
   }
diff --git a/src/notetag.hpp b/src/notetag.hpp
index 99b81bf0..57b758f5 100644
--- a/src/notetag.hpp
+++ b/src/notetag.hpp
@@ -1,7 +1,7 @@
 /*
  * gnote
  *
- * Copyright (C) 2011,2013-2014,2017,2019 Aurimas Cernius
+ * Copyright (C) 2011,2013-2014,2017,2019,2021 Aurimas Cernius
  * Copyright (C) 2009 Hubert Figuiere
  *
  * This program is free software: you can redistribute it and/or modify
@@ -154,7 +154,7 @@ public:
     {
       m_palette_foreground = value;
       // XXX We should also watch theme changes.
-      property_foreground_gdk().set_value(render_foreground(value));
+      property_foreground_rgba().set_value(render_foreground(value));
     }
 protected:
   NoteTag(const Glib::ustring & tag_name, int flags = 0);
@@ -166,8 +166,8 @@ protected:
   virtual bool on_event(const Glib::RefPtr<Glib::Object> &, GdkEvent *, const Gtk::TextIter & ) override;
   virtual bool on_activate(const NoteEditor & , const Gtk::TextIter &, const Gtk::TextIter &);
 private:
-  Gdk::Color get_background() const;
-  Gdk::Color render_foreground(ContrastPaletteColor symbol);
+  Gdk::RGBA get_background() const;
+  Gdk::RGBA render_foreground(ContrastPaletteColor symbol);
 
   Glib::ustring       m_element_name;
   Glib::RefPtr<Gtk::TextMark> m_widget_location;