From 9386847cc9c6b61a33dda35adee8a14ee43c341a Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Sun, 18 Feb 2024 18:19:35 +0100
Subject: [PATCH] Fix ACE Compressor inplace processing #9636

---
 libs/ardour/parameter_descriptor.cc | 13 ++++++++++++-
 libs/plugins/a-comp.lv2/a-comp.c    | 10 ++++++++--
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/libs/ardour/parameter_descriptor.cc b/libs/ardour/parameter_descriptor.cc
index a4fed84675..ddd32244f5 100644
--- a/libs/ardour/parameter_descriptor.cc
+++ b/libs/ardour/parameter_descriptor.cc
@@ -138,9 +138,20 @@ ParameterDescriptor::ParameterDescriptor(const Evoral::Parameter& parameter)
 	case MidiChannelPressureAutomation:
 	case MidiNotePressureAutomation:
 		lower  = 0.0;
-		normal = 0.0;
 		upper  = 127.0;
 		print_fmt = "%.0f";
+		switch(parameter.id()) {
+			case 7: // Channel Volume (MSB)
+				normal = 127;
+				break;
+			case 8: // Balance (MSB)
+			case 10: // Pan (MSB)
+				normal = 64;
+				break;
+			default:
+				normal = 0.0;
+				break;
+		}
 		break;
 	case MidiPitchBenderAutomation:
 		lower  = 0.0;
diff --git a/libs/plugins/a-comp.lv2/a-comp.c b/libs/plugins/a-comp.lv2/a-comp.c
index d533754c21..3557fc01cf 100644
--- a/libs/plugins/a-comp.lv2/a-comp.c
+++ b/libs/plugins/a-comp.lv2/a-comp.c
@@ -338,6 +338,12 @@ run(LV2_Handle instance, uint32_t n_samples)
 		makeup_target = 1.f;
 	}
 
+	for (uint32_t c=0; c<n_channels; ++c) {
+		if (ins[c] != outs[c]) {
+			memcpy (outs[c], ins[c], sizeof (float) * n_samples);
+		}
+	}
+
 #ifdef LV2_EXTENDED
 	if (acomp->v_knee != *acomp->knee) {
 		acomp->v_knee = *acomp->knee;
@@ -366,7 +372,7 @@ run(LV2_Handle instance, uint32_t n_samples)
 	for (i = 0; i < n_samples; i++) {
 		maxabs = 0.f;
 		for (uint32_t c=0; c<n_channels; ++c) {
-			maxabs = fmaxf(fabsf(ins[c][i]), maxabs);
+			maxabs = fmaxf(fabsf(outs[c][i]), maxabs);
 		}
 		sc0 = sc[i];
 		ingain = usesidechain ? fabs(sc0) : maxabs;
@@ -409,7 +415,7 @@ run(LV2_Handle instance, uint32_t n_samples)
 		makeup_gain += tau * (makeup_target - makeup_gain);
 
 		for (uint32_t c=0; c<n_channels; ++c) {
-			float out = ins[c][i] * Lgain * makeup_gain;
+			float out = outs[c][i] * Lgain * makeup_gain;
 			outs[c][i] = out;
 			out = fabsf (out);
 			if (out > max_out) {