From cc7eca74534e3699d15721d9b4c9c9efed45567f Mon Sep 17 00:00:00 2001
From: Jan Lentfer <jan.lentfer@web.de>
Date: Sun, 9 Feb 2020 16:29:07 +0100
Subject: [PATCH] LCXL: Adopt pan knob behaviour

    * "left/right" changed in A6, adopt for this
    * add a pick_up_rev function to honour this
---
 libs/surfaces/launch_control_xl/controllers.cc       | 5 +++--
 libs/surfaces/launch_control_xl/launch_control_xl.cc | 7 +++++++
 libs/surfaces/launch_control_xl/launch_control_xl.h  | 2 ++
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/libs/surfaces/launch_control_xl/controllers.cc b/libs/surfaces/launch_control_xl/controllers.cc
index a25504b885..4e93656618 100644
--- a/libs/surfaces/launch_control_xl/controllers.cc
+++ b/libs/surfaces/launch_control_xl/controllers.cc
@@ -879,8 +879,9 @@ LaunchControlXL::knob_pan(uint8_t n)
 	}
 
 
-	if (ac && check_pick_up(knob, ac)) {
-		ac->set_value ( ac->interface_to_internal( knob->value() / 127.0), PBD::Controllable::UseGroup );
+	if (ac && check_pick_up_rev(knob, ac)) {
+		DEBUG_TRACE (DEBUG::LaunchControlXL, string_compose ("knob->value: '%1'\n", (int) knob->value()));
+		ac->set_value (ac->interface_to_internal ((127 - knob->value()) / 127.0), PBD::Controllable::UseGroup);
 	}
 }
 
diff --git a/libs/surfaces/launch_control_xl/launch_control_xl.cc b/libs/surfaces/launch_control_xl/launch_control_xl.cc
index f659ea685c..0fd5cca763 100644
--- a/libs/surfaces/launch_control_xl/launch_control_xl.cc
+++ b/libs/surfaces/launch_control_xl/launch_control_xl.cc
@@ -620,6 +620,13 @@ LaunchControlXL::check_pick_up(boost::shared_ptr<Controller> controller, boost::
 	return ( abs( controller->value() / 127.0 -  ac->internal_to_interface(ac->get_value()) ) < 0.007875 );
 }
 
+bool
+LaunchControlXL::check_pick_up_rev (boost::shared_ptr<Controller> controller, boost::shared_ptr<AutomationControl> ac)
+{
+	/* returns false until 127 minus the controller value matches with the current setting of the stripable's ac */
+	return (abs ((127 - controller->value()) / 127.0  - ac->internal_to_interface (ac->get_value())) < 0.007875);
+}
+
 void
 LaunchControlXL::handle_midi_controller_message (MIDI::Parser& parser, MIDI::EventTwoBytes* ev, MIDI::channel_t chan)
 {
diff --git a/libs/surfaces/launch_control_xl/launch_control_xl.h b/libs/surfaces/launch_control_xl/launch_control_xl.h
index 166200aff3..af041a302c 100644
--- a/libs/surfaces/launch_control_xl/launch_control_xl.h
+++ b/libs/surfaces/launch_control_xl/launch_control_xl.h
@@ -496,6 +496,8 @@ private:
 	void handle_button_message(boost::shared_ptr<Button> button, MIDI::EventTwoBytes *);
 
 	bool check_pick_up(boost::shared_ptr<Controller> controller, boost::shared_ptr<ARDOUR::AutomationControl> ac);
+	bool check_pick_up_rev(boost::shared_ptr<Controller> controller, boost::shared_ptr<ARDOUR::AutomationControl> ac);
+
 
 	void handle_midi_controller_message(MIDI::Parser &, MIDI::EventTwoBytes *, MIDI::channel_t chan);
 	void handle_midi_note_on_message(MIDI::Parser &, MIDI::EventTwoBytes *, MIDI::channel_t chan);