Re: midi bug remains in 2.13.58

[Jan Nieuwenhuizen]

- Hu Haipeng writes:

The patch below may fix this, when using

    \set Score.midiChannelMapping = #'staff

> Ok, Here's my example, just 4 bars.

It is indeed just 4 bars.  Although I can look at the warning,
this example is not usable as a regtest or tiny example.  It
is still quite difficult [for me] to verify that what is meant
in this .ly, actually arrives into the .midi.

Possibly with something like

violin = { \set Staff.midiInstrument = "violin" a4 a }
changer = {
  \set Staff.midiInstrument = "midi-instr 1"
  c128
  \set Staff.midiInstrument = "midi-instr 2"
  c128
  ..
  \set Staff.midiInstrument = "midi-instr 17"
  c128
  \set Staff.midiInstrument = "celesta"
  c4
}

it would be feasible to verify that, in the end, we hear a
violin and a celesta.  Not sure how to make a better test
for this that could serve as a regtest.

Jan.

>From e0524f8ebdd4bcf908b8e3bce66e09670b8c30ed Mon Sep 17 00:00:00 2001
From: Jan Nieuwenhuizen <address@hidden>
Date: Sun, 17 Apr 2011 12:08:04 +0200
Subject: [PATCH] MIDI: in midiChannelMapping = #'staff mode, keep to one 
channel.  Fixes #xxxx.

---
 lily/staff-performer.cc |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/lily/staff-performer.cc b/lily/staff-performer.cc
index 5aafabe..90fe5d7 100644
--- a/lily/staff-performer.cc
+++ b/lily/staff-performer.cc
@@ -216,6 +216,9 @@ Staff_performer::get_channel (string instrument)
     ? channel_map_
     : static_channel_map_;
 
+  if (channel_ && channel_mapping == ly_symbol2scm ("staff"))
+    return channel_;
+
   map<string, int>::const_iterator i = channel_map.find (instrument);
   if (i != channel_map.end ())
     return i->second;
-- 
1.7.1

-- 
Jan Nieuwenhuizen <address@hidden> | GNU LilyPond http://lilypond.org
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