decrease the default opacity of "dragged region" (in all themes)

* during drag and trim operations, we use "dragging region" transparency
  so you can see the audio data beneath your region(s)

* we already do this for region-end-trim fade drags, which is a special
   kind of trim operation, accessed from the 'lower' drag handle

* now we also trigger transparency for regular fade trims.

   see discussion at:
https://discourse.ardour.org/t/regions-transparency-in-7-2/108060/31

gtk2_ardour/editor_drag.cc

@@ -4046,7 +4046,7 @@ FadeInDrag::setup_pointer_offset ()
 }
 
 void
-FadeInDrag::motion (GdkEvent* event, bool)
+FadeInDrag::motion (GdkEvent* event, bool first_motion)
 {
 
 	timepos_t tpos (timepos_t (_editor->canvas_event_sample (event)) + snap_delta (event->button.state));
@@ -4075,6 +4075,10 @@ FadeInDrag::motion (GdkEvent* event, bool)
 			continue;
 		}
 
+		if (first_motion) {
+			tmp->drag_start ();
+		}
+
 		tmp->reset_fade_in_shape_width (tmp->audio_region(), fade_length);
 	}
 
@@ -4116,6 +4120,8 @@ FadeInDrag::finished (GdkEvent* event, bool movement_occurred)
 			continue;
 		}
 
+		tmp->drag_end ();
+
 		boost::shared_ptr<AutomationList> alist = tmp->audio_region()->fade_in();
 		XMLNode &before = alist->get_state();
 
@@ -4145,6 +4151,8 @@ FadeInDrag::aborted (bool)
 			continue;
 		}
 
+		tmp->drag_end ();
+
 		tmp->reset_fade_in_shape_width (tmp->audio_region(), tmp->audio_region()->fade_in()->back()->when.samples());
 	}
 }
@@ -4177,7 +4185,7 @@ FadeOutDrag::setup_pointer_offset ()
 }
 
 void
-FadeOutDrag::motion (GdkEvent* event, bool)
+FadeOutDrag::motion (GdkEvent* event, bool first_motion)
 {
 	samplecnt_t fade_length;
 
@@ -4205,6 +4213,10 @@ FadeOutDrag::motion (GdkEvent* event, bool)
 			continue;
 		}
 
+		if (first_motion) {
+			tmp->drag_start ();
+		}
+
 		tmp->reset_fade_out_shape_width (tmp->audio_region(), fade_length);
 	}
 
@@ -4247,6 +4259,8 @@ FadeOutDrag::finished (GdkEvent* event, bool movement_occurred)
 			continue;
 		}
 
+		tmp->drag_end ();
+
 		boost::shared_ptr<AutomationList> alist = tmp->audio_region()->fade_out();
 		XMLNode &before = alist->get_state();
 
@@ -4276,6 +4290,8 @@ FadeOutDrag::aborted (bool)
 			continue;
 		}
 
+		tmp->drag_end ();
+
 		tmp->reset_fade_out_shape_width (tmp->audio_region(), tmp->audio_region()->fade_out()->back()->when.samples());
 	}
 }

gtk2_ardour/themes/blueberry_milk-ardour.colors

@@ -482,7 +482,7 @@
     <Modifier name="automation track fill" modifier="= alpha:0.3"/>
     <Modifier name="covered region base" modifier="= alpha:0.7"/>
     <Modifier name="crossfade alpha" modifier="= alpha:0.1803"/>
-    <Modifier name="dragging region" modifier="= alpha:0.9"/>
+    <Modifier name="dragging region" modifier="= alpha:0.5"/>
     <Modifier name="editable region" modifier="= alpha:0.15"/>
     <Modifier name="gain line inactive" modifier="= alpha:0.7725"/>
     <Modifier name="ghost track base" modifier="= alpha:0.640782"/>

gtk2_ardour/themes/caineville-ardour.colors

@@ -483,7 +483,7 @@
     <Modifier name="automation track fill" modifier="= alpha:0.3"/>
     <Modifier name="covered region base" modifier="= alpha:0.7"/>
     <Modifier name="crossfade alpha" modifier="= alpha:0.1803"/>
-    <Modifier name="dragging region" modifier="= alpha:0.9"/>
+    <Modifier name="dragging region" modifier="= alpha:0.5"/>
     <Modifier name="editable region" modifier="= alpha:0.15"/>
     <Modifier name="gain line inactive" modifier="= alpha:0.7725"/>
     <Modifier name="ghost track base" modifier="= alpha:0.640782"/>

gtk2_ardour/themes/clear_gray-ardour.colors

@@ -483,7 +483,7 @@
     <Modifier name="automation track fill" modifier="= alpha:0.3"/>
     <Modifier name="covered region base" modifier="= alpha:0.7"/>
     <Modifier name="crossfade alpha" modifier="= alpha:0.1803"/>
-    <Modifier name="dragging region" modifier="= alpha:0.9"/>
+    <Modifier name="dragging region" modifier="= alpha:0.5"/>
     <Modifier name="editable region" modifier="= alpha:0.15"/>
     <Modifier name="gain line inactive" modifier="= alpha:0.7725"/>
     <Modifier name="ghost track base" modifier="= alpha:0.640782"/>

gtk2_ardour/themes/cubasish-ardour.colors

@@ -483,7 +483,7 @@
     <Modifier name="automation track fill" modifier="= alpha:0.3"/>
     <Modifier name="covered region base" modifier="= alpha:0.7"/>
     <Modifier name="crossfade alpha" modifier="= alpha:0.1803"/>
-    <Modifier name="dragging region" modifier="= alpha:0.9"/>
+    <Modifier name="dragging region" modifier="= alpha:0.5"/>
     <Modifier name="editable region" modifier="= alpha:0.15"/>
     <Modifier name="gain line inactive" modifier="= alpha:0.7725"/>
     <Modifier name="ghost track base" modifier="= alpha:0.640782"/>

gtk2_ardour/themes/dark-ardour.colors

@@ -484,7 +484,7 @@
     <Modifier name="automation track fill" modifier="= alpha:0.3"/>
     <Modifier name="covered region base" modifier="= alpha:0.7"/>
     <Modifier name="crossfade alpha" modifier="= alpha:0.1803"/>
-    <Modifier name="dragging region" modifier="= alpha:0.9"/>
+    <Modifier name="dragging region" modifier="= alpha:0.5"/>
     <Modifier name="editable region" modifier="= alpha:0.25"/>
     <Modifier name="gain line inactive" modifier="= alpha:0.7725"/>
     <Modifier name="ghost track base" modifier="= alpha:0.640782"/>

gtk2_ardour/themes/diehard3-ardour.colors

@@ -484,7 +484,7 @@
     <Modifier name="automation track fill" modifier="= alpha:0.29999999999999999"/>
     <Modifier name="covered region base" modifier="= alpha:0.43717289719626168"/>
     <Modifier name="crossfade alpha" modifier="= alpha:0.18029999999999999"/>
-    <Modifier name="dragging region" modifier="= alpha:0.90000000000000002"/>
+    <Modifier name="dragging region" modifier="= alpha:0.5"/>
     <Modifier name="editable region" modifier="= alpha:0.1202803738317757"/>
     <Modifier name="gain line inactive" modifier="= alpha:0.77249999999999996"/>
     <Modifier name="ghost track base" modifier="= alpha:0.64078199999999996"/>

gtk2_ardour/themes/recbox-ardour.colors

@@ -484,7 +484,7 @@
     <Modifier name="automation track fill" modifier="= alpha:0.29999999999999999"/>
     <Modifier name="covered region base" modifier="= alpha:0.69999999999999996"/>
     <Modifier name="crossfade alpha" modifier="= alpha:0.18029999999999999"/>
-    <Modifier name="dragging region" modifier="= alpha:0.90000000000000002"/>
+    <Modifier name="dragging region" modifier="= alpha:0.5"/>
     <Modifier name="editable region" modifier="= alpha:0.25"/>
     <Modifier name="gain line inactive" modifier="= alpha:0.77249999999999996"/>
     <Modifier name="ghost track base" modifier="= alpha:0.64078199999999996"/>

gtk2_ardour/themes/unastudia-ardour.colors

@@ -482,7 +482,7 @@
     <Modifier name="automation track fill" modifier="= alpha:0.3"/>
     <Modifier name="covered region base" modifier="= alpha:0.7"/>
     <Modifier name="crossfade alpha" modifier="= alpha:0.1803"/>
-    <Modifier name="dragging region" modifier="= alpha:0.9"/>
+    <Modifier name="dragging region" modifier="= alpha:0.5"/>
     <Modifier name="editable region" modifier="= alpha:0.15"/>
     <Modifier name="gain line inactive" modifier="= alpha:0.7725"/>
     <Modifier name="ghost track base" modifier="= alpha:0.640782"/>

gtk2_ardour/themes/xcolors-ardour.colors

@@ -483,7 +483,7 @@
     <Modifier name="automation track fill" modifier="= alpha:0.5"/>
     <Modifier name="covered region base" modifier="= alpha:0.7"/>
     <Modifier name="crossfade alpha" modifier="= alpha:0.2"/>
-    <Modifier name="dragging region" modifier="= alpha:0.9"/>
+    <Modifier name="dragging region" modifier="= alpha:0.5"/>
     <Modifier name="editable region" modifier="= alpha:0.1"/>
     <Modifier name="gain line inactive" modifier="= alpha:0.8"/>
     <Modifier name="ghost track base" modifier="= alpha:0.7"/>