oversample meter faceplate image surfaces

Works around issues with pango on windows,
fixes crude text on OSX/retina and can provide sub-pixel
rendering on GNU/Linux/X11.

diff --git a/gtk2_ardour/meter_patterns.cc b/gtk2_ardour/meter_patterns.cc
index de95915c36a9a47dfbf0bb3774175b71a2ee23cd..675e567df69071d70a31421f5555515bd5ca4824 100644 (file)
--- a/gtk2_ardour/meter_patterns.cc
+++ b/gtk2_ardour/meter_patterns.cc
@@ -619,8 +619,14 @@ meter_render_metrics (Gtk::Widget& w, MeterType type, vector<DataType> types)
                tickright = true;
        }
 
+#ifdef NO_OVERSAMPLE
        cairo_surface_t* surface = cairo_image_surface_create (CAIRO_FORMAT_RGB24, width, height);
        cairo_t* cr = cairo_create (surface);
+#else
+       cairo_surface_t* surface = cairo_image_surface_create (CAIRO_FORMAT_RGB24, width*2, height*2);
+       cairo_t* cr = cairo_create (surface);
+       cairo_scale(cr, 2.0, 2.0);
+#endif
        Glib::RefPtr<Pango::Layout> layout = Pango::Layout::create(w.get_pango_context());
 
        Pango::AttrList audio_font_attributes;
@@ -632,7 +638,7 @@ meter_render_metrics (Gtk::Widget& w, MeterType type, vector<DataType> types)
 
        font = Pango::FontDescription (ARDOUR_UI::config()->get_SmallMonospaceFont());
 #ifdef __APPLE__
-       const double fixfontsize = 1.125;
+       const double fixfontsize = 1.0;
 #else
        // counter-act global font-scaling.
        const double fixfontsize = std::min(1.0, 0.9 / sqrtf(ARDOUR_UI::ui_scale));
@@ -1086,12 +1092,19 @@ ArdourMeter::meter_expose_metrics (GdkEventExpose *ev, MeterType type, std::vect
        }
 
        cairo_move_to (cr, 0, 0);
-       cairo_set_source (cr, pattern);
 
        gint width, height;
        win->get_size (width, height);
-
+#ifdef NO_OVERSAMPLE
+       cairo_set_source (cr, pattern);
        cairo_rectangle (cr, 0, 0, width, height);
+#else
+       cairo_scale(cr, 0.5, 0.5);
+       cairo_set_antialias(cr, CAIRO_ANTIALIAS_BEST);
+       cairo_set_source (cr, pattern);
+       cairo_rectangle (cr, 0, 0, width * 2., height * 2.);
+#endif
+
        cairo_fill (cr);
 
        cairo_destroy (cr);