change handling of MIDI gain so that we present a linear fader spanning 0..127. this is based on the realization that we actually have no idea what the MIDI receiver will do with velocity and/or CC #7 values, and so trying to pretend that we can provide some kind of dB value in the display or the behaviour of the fader is completely wrong; ALSO: fix keyboard entry of fader levels for non EN locales (#5027)

git-svn-id: svn://localhost/ardour2/branches/3.0@13480 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 13 insertions, 11 deletions

diff --git a/libs/ardour/amp.cc b/libs/ardour/amp.cc
index d68f73ef3e..c0cd404cf6 100644
--- a/libs/ardour/amp.cc
+++ b/libs/ardour/amp.cc
@@ -33,6 +33,10 @@
 
 using namespace ARDOUR;
 using namespace PBD;
+using std::min;
+
+/* gain range of -inf to +6dB, default 0dB */
+const float Amp::max_gain_coefficient = 1.99526231f;
 
 Amp::Amp (Session& s)
 	: Processor(s, "Amp")
@@ -42,8 +46,7 @@ Amp::Amp (Session& s)
 	, _gain_automation_buffer(0)
 {
 	Evoral::Parameter p (GainAutomation);
-	/* gain range of -inf to +6dB, default 0dB */
-	p.set_range (0, 1.99526231f, 1, false);
+	p.set_range (0, max_gain_coefficient, 1, false);
 	boost::shared_ptr<AutomationList> gl (new AutomationList (p));
 	_gain_control = boost::shared_ptr<GainControl> (new GainControl (X_("gaincontrol"), s, this, p, gl));
 	_gain_control->set_flags (Controllable::GainLike);
@@ -114,11 +117,12 @@ Amp::run (BufferSet& bufs, framepos_t /*start_frame*/, framepos_t /*end_frame*/,
 				for (BufferSet::midi_iterator i = bufs.midi_begin(); i != bufs.midi_end(); ++i) {
 
 					MidiBuffer& mb (*i);
-
+					const float midi_velocity_factor = gain_coefficient_to_midi_velocity_factor (_current_gain);
+					
 					for (MidiBuffer::iterator m = mb.begin(); m != mb.end(); ++m) {
 						Evoral::MIDIEvent<MidiBuffer::TimeType> ev = *m;
 						if (ev.is_note_on()) {
-							ev.scale_velocity (_current_gain);
+							ev.scale_velocity (midi_velocity_factor);
 						}
 					}
 				}
@@ -172,8 +176,8 @@ Amp::apply_gain (BufferSet& bufs, framecnt_t nframes, gain_t initial, gain_t tar
 			Evoral::MIDIEvent<MidiBuffer::TimeType> ev = *m;
 
 			if (ev.is_note_on()) {
-				gain_t scale = delta * (ev.time()/(double) nframes);
-				ev.scale_velocity (initial+scale);
+				const gain_t scale = delta * (ev.time()/(double) nframes);
+				ev.scale_velocity (gain_coefficient_to_midi_velocity_factor (initial+scale));
 			}
 		}
 	}
@@ -331,11 +335,12 @@ Amp::apply_simple_gain (BufferSet& bufs, framecnt_t nframes, gain_t target)
 
 		for (BufferSet::midi_iterator i = bufs.midi_begin(); i != bufs.midi_end(); ++i) {
 			MidiBuffer& mb (*i);
+			const float midi_velocity_factor = gain_coefficient_to_midi_velocity_factor (target);
 
 			for (MidiBuffer::iterator m = mb.begin(); m != mb.end(); ++m) {
 				Evoral::MIDIEvent<MidiBuffer::TimeType> ev = *m;
 				if (ev.is_note_on()) {
-					ev.scale_velocity (target);
+					ev.scale_velocity (midi_velocity_factor);
 				}
 			}
 		}
@@ -371,10 +376,7 @@ Amp::inc_gain (gain_t factor, void *src)
 void
 Amp::set_gain (gain_t val, void *src)
 {
-	// max gain at about +6dB (10.0 ^ ( 6 dB * 0.05))
-	if (val > 1.99526231f) {
-		val = 1.99526231f;
-	}
+	val = min (val, max_gain_coefficient);
 
 	if (src != _gain_control.get()) {
 		_gain_control->set_value (val);