+int
+ARDOUR::LuaAPI::color_to_rgba (lua_State *L)
+{
+ int top = lua_gettop (L);
+ if (top < 1) {
+ return luaL_argerror (L, 1, "invalid number of arguments, color_to_rgba (uint32_t)");
+ }
+ uint32_t color = luabridge::Stack<uint32_t>::get (L, 1);
+ double r, g, b, a;
+
+ /* libardour is no user of libcanvas, otherwise
+ * we could just call
+ * Gtkmm2ext::color_to_rgba (color, r, g, b, a);
+ */
+ r = ((color >> 24) & 0xff) / 255.0;
+ g = ((color >> 16) & 0xff) / 255.0;
+ b = ((color >> 8) & 0xff) / 255.0;
+ a = ((color >> 0) & 0xff) / 255.0;
+
+ luabridge::Stack <double>::push (L, r);
+ luabridge::Stack <double>::push (L, g);
+ luabridge::Stack <double>::push (L, b);
+ luabridge::Stack <double>::push (L, a);
+ return 4;
+}
+