From 87ab1625ffae87769ee973e6ebee2723daf8ee89 Mon Sep 17 00:00:00 2001
From: Paul Davis <paul@linuxaudiosystems.com>
Date: Wed, 21 Sep 2016 19:25:36 -0500
Subject: [PATCH] push2: volume pots now work like non-linear faders, as
 desired

---
 libs/surfaces/push2/knob.cc |  1 +
 libs/surfaces/push2/mix.cc  | 11 ++++++++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/libs/surfaces/push2/knob.cc b/libs/surfaces/push2/knob.cc
index 71edaf5b5c..29dffe31bb 100644
--- a/libs/surfaces/push2/knob.cc
+++ b/libs/surfaces/push2/knob.cc
@@ -23,6 +23,7 @@
 
 #include "ardour/automation_control.h"
 #include "ardour/dB.h"
+#include "ardour/utils.h"
 
 #include "gtkmm2ext/gui_thread.h"
 #include "gtkmm2ext/rgb_macros.h"
diff --git a/libs/surfaces/push2/mix.cc b/libs/surfaces/push2/mix.cc
index 169eec3140..bf08dad873 100644
--- a/libs/surfaces/push2/mix.cc
+++ b/libs/surfaces/push2/mix.cc
@@ -40,6 +40,7 @@
 #include "ardour/midi_port.h"
 #include "ardour/session.h"
 #include "ardour/tempo.h"
+#include "ardour/utils.h"
 #include "ardour/vca_manager.h"
 
 #include "canvas/colors.h"
@@ -399,7 +400,15 @@ MixLayout::strip_vpot (int n, int delta)
 	boost::shared_ptr<Controllable> ac = knobs[n]->controllable();
 
 	if (ac) {
-		ac->set_value (ac->get_value() + ((2.0/64.0) * delta), PBD::Controllable::UseGroup);
+		if (ac->is_gain_like()) {
+			/* 128 steps from fader position 0 to 1.0 ..
+			 */
+			const double new_fader_position = min (1.0, max (0.0, ac->internal_to_interface (ac->get_value()) + ((1.0 / 128.0) * delta)));
+			ac->set_value (ac->interface_to_internal (new_fader_position), PBD::Controllable::UseGroup);
+		} else {
+			/* 128 steps from min to max */
+			ac->set_value (ac->get_value() + (((ac->upper() - ac->lower()) / 128.0) * delta) , PBD::Controllable::UseGroup);
+		}
 	}
 }