From 8ba21e7fff39f7cc389549b7f21bbe5a35bb2b15 Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Mon, 26 Sep 2022 14:56:50 +0200
Subject: [PATCH] Fix region-gain when trimming, cutting or partitioning
 regions

The during trim-front, the call order is
 1. Region::set_position_internal
 2. Region::set_length_internal

::set_position_internal sets `_last_length.set_position (position());`
but the later call ::set_length_internal does `_last_length = _length;`
This sets last_position() == position(), and later Region::mid_thaw()
does not call Region::recompute_at_start().

Region gain envelope was not updated.

see also 00a1b7cb240556c and 13d10582f0ce4
---
 libs/ardour/region.cc | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libs/ardour/region.cc b/libs/ardour/region.cc
index 019ccac905..9b90a2a10e 100644
--- a/libs/ardour/region.cc
+++ b/libs/ardour/region.cc
@@ -492,10 +492,13 @@ void
 Region::set_length_internal (timecnt_t const & len)
 {
 	timecnt_t l (len);
+	timepos_t p (_last_length.position());
 
 	l.set_position (position());
 
 	_last_length = _length;
+	_last_length.set_position (p);
+
 	_length = l;
 }