Timeline: Tweak style of measure lines.

timeline/src/Timeline.C

@@ -997,20 +997,32 @@ Timeline::draw_measure_cb ( nframes_t frame, const BBT &bbt, void *v )
 {
     Timeline *o = (Timeline*)v;
 
-    Fl_Color c = FL_LIGHT3;
-
     if ( o->panzoomer->zoom() >= 15 )
         return;
+    
+    Fl_Color mc = FL_LIGHT3;
+    Fl_Color bc = FL_LIGHT2;
+    Fl_Color c;
+    Fl_Color ct = fl_contrast( mc, FL_BACKGROUND_COLOR );
+
+    if ( FL_BLACK == ct )
+    {
+	/* in a light color scheme mode */
+	mc = fl_rgb_color(30,30,30);
+	bc = FL_DARK3;
+    }
 
     if ( bbt.beat )
     {
         if ( o->panzoomer->zoom() > 12 )
             return;
         else
-            c = FL_DARK1;
+	    c = bc;
     }
+    else
+	c = mc;
 
-    fl_color( fl_color_add_alpha( c, 64 ) );
+    fl_color( fl_color_add_alpha( c, 127 ) );
     
     const int x = timeline->ts_to_x( frame - timeline->xoffset ) + Track::width();