From: Paul Davis <paul@linuxaudiosystems.com>
Date: Thu, 23 Jul 2015 21:38:04 +0000 (-0400)
Subject: if _need_bg is set to false in a CairoWidget, then don't actually draw the background
X-Git-Tag: 5.0-pre0~1585
X-Git-Url: https://main.carlh.net/gitweb/?a=commitdiff_plain;h=a48684c692a0d8e567bf8ca80f746fb8f05fede1;p=ardour.git

if _need_bg is set to false in a CairoWidget, then don't actually draw the background
---

diff --git a/libs/gtkmm2ext/cairo_widget.cc b/libs/gtkmm2ext/cairo_widget.cc
index 0f34a3ffdb..3b4da2f3c9 100644
--- a/libs/gtkmm2ext/cairo_widget.cc
+++ b/libs/gtkmm2ext/cairo_widget.cc
@@ -183,15 +183,21 @@ CairoWidget::on_expose_event (GdkEventExpose *ev)
 #endif
 
 	cr->rectangle (ev->area.x, ev->area.y, ev->area.width, ev->area.height);
-	cr->clip_preserve ();
 
-	/* paint expose area the color of the parent window bg
-	*/
-
-	Gdk::Color bg (get_parent_bg());
-
-	cr->set_source_rgb (bg.get_red_p(), bg.get_green_p(), bg.get_blue_p());
-	cr->fill ();
+	if (_need_bg) {
+		cr->clip_preserve ();
+		
+		/* paint expose area the color of the parent window bg
+		 */
+		
+		Gdk::Color bg (get_parent_bg());
+		
+		cr->set_source_rgb (bg.get_red_p(), bg.get_green_p(), bg.get_blue_p());
+		cr->fill ();
+	} else {
+		std::cerr << get_name() << " skipped bg fill\n";
+		cr->clip ();
+	}
 
 	cairo_rectangle_t expose_area;
 	expose_area.x = ev->area.x;