From 0747e618a4fa23048e8a8806fd4e1319555c4c11 Mon Sep 17 00:00:00 2001
From: Valentin <v.villenave@gmail.com>
Date: Thu, 18 Dec 2008 15:10:58 +0100
Subject: [PATCH] Piano staves problem: FIXED

At last!! Took me a while, but now the piano staves
only appear together, whenever one of the two hands
is playing something.

The code also supports cross-staff voices, ottavas,
clef changes, internal voices etc. A slight bug remains
with cross-staff slurs, but IMHO this is quite good
already.
---
 definitions/functions.ly | 44 ++++++++++++++++++++++++++++----------------
 definitions/settings.ly  | 16 ++++++++--------
 master/master.ly         |  6 +++---
 3 files changed, 39 insertions(+), 27 deletions(-)

diff --git a/definitions/functions.ly b/definitions/functions.ly
index 61b802a..d1408a5 100755
--- a/definitions/functions.ly
+++ b/definitions/functions.ly
@@ -47,18 +47,22 @@ parallel=
 
 %%% Piano stuff (Issue #442 workaround)
 
+#(define (remove music)
+"Sends the whole thing to Devnull whenever possible"
+ (context-spec-music music 'Devnull))
+
 #(define (event-filter event)
-    (let ((n (ly:music-property event 'name)))
-    (not
-      (or     ;; add here event name you do NOT want
-       (eq? n 'ContextSpeccedMusic)
-       (eq? n 'ContextChange)
-       (eq? n 'SimultaneousMusic))
-  )))
+ (let ((n (ly:music-property event 'name)))
+  (if (or
+    (eq? n 'ContextSpeccedMusic) ; to avoid clefs and ottavas
+    (eq? n 'ContextChange)) ; cross-staff voices are supported
+    (music-map remove event))
+  (if (eq? n 'SimultaneousMusic) ; we don't want a new Voice to be created
+    (ly:music-set-property! event 'name 'NoteEvent))))
 
 makeGhost =
 #(define-music-function (parser location music) (ly:music?)
-  (context-spec-music (music-filter event-filter music) 'PseudoVoice))
+ (context-spec-music (music-filter event-filter music) 'PseudoVoice))
 
 showAnyway =
 #(define-music-function (parser location music) (ly:music?)
@@ -81,12 +85,12 @@ PianoDeuxMains=
     \new Staff = "md" \with { \remove Accidental_engraver }
     <<
      \new Voice \with { \consists Accidental_engraver } { \clef treble $droite }
-     %\new Voice { \makeGhost $gauche }
+     \new Voice { \makeGhost $gauche }
     >>
     \new Staff = "mg" \with { \remove Accidental_engraver }
     <<
      \new Voice \with { \consists Accidental_engraver } { \clef bass $gauche }
-     %\new Voice { \makeGhost $droite }
+     \new Voice { \makeGhost $droite }
     >>
   >>
 #})
@@ -97,12 +101,20 @@ gauche = { \change Staff = "percuGauche" }
 
 PercuDeuxMains=
 #(define-music-function (parser location droite gauche) (ly:music? ly:music?)
-#{ << %%%FIXME: I /definitely/ should get rid of this option.
-\new Staff = "percuDroite"
-{ \clef treble $droite }
-\new Staff = "percuGauche" \with { \override VerticalAxisGroup #'remove-empty = ##f }
-{ \clef bass $gauche }
->> #})
+#{
+  \new PianoStaff <<
+    \new Staff = "percuDroite" \with { \remove Accidental_engraver }
+    <<
+     \new Voice \with { \consists Accidental_engraver } { \clef treble $droite }
+     \new Voice { \makeGhost $gauche }
+    >>
+    \new Staff = "percuGauche" \with { \remove Accidental_engraver }
+    <<
+     \new Voice \with { \consists Accidental_engraver } { \clef bass $gauche }
+     \new Voice { \makeGhost $droite }
+    >>
+  >>
+#})
 
 
 %% Music formatting -----------------------------------------------%
diff --git a/definitions/settings.ly b/definitions/settings.ly
index 6153c31..ae8762f 100755
--- a/definitions/settings.ly
+++ b/definitions/settings.ly
@@ -178,14 +178,14 @@ includeLayout = \layout {
     \remove Mark_engraver
     \accepts GhostVoice
   }
-    \context {
+  \context {
     \name PseudoVoice
     \alias Voice
-    \type "Engraver_group"
-    \consists "Note_heads_engraver"
+    \type Engraver_group
+    \consists Note_heads_engraver
     \consists Pitch_squash_engraver
     squashedPosition = #0
-    \override NoteHead #'stencil = ##f
+    \override NoteHead #'stencil = #empty-stencil
   }
   \context {
     \Staff
@@ -271,14 +271,14 @@ includePartsLayout = \layout {
     \remove Mark_engraver
     \accepts GhostVoice
   }
-    \context {
+  \context {
     \name PseudoVoice
     \alias Voice
-    \type "Engraver_group"
-    \consists "Note_heads_engraver"
+    \type Engraver_group
+    \consists Note_heads_engraver
     \consists Pitch_squash_engraver
     squashedPosition = #0
-    \override NoteHead #'stencil = ##f
+    \override NoteHead #'stencil = #empty-stencil
   }
   \context {
     \Staff
diff --git a/master/master.ly b/master/master.ly
index 901059e..cc33abb 100644
--- a/master/master.ly
+++ b/master/master.ly
@@ -100,19 +100,19 @@
     acte = \ActeDeuxTitre
     piece = \SceneUnTitre
   }
-} %}
+} %
 \score {
   \ActeDeuxSceneUnBis
   \header {
     piece = \Separateur
   }
-} %{
+} %}
 \score {
   \ActeDeuxSceneDeux
   \header {
     piece = \SceneDeuxTitre
   }
-} %
+} %{
 \score {
   \ActeDeuxSceneTrois
   \header {
-- 
2.11.4.GIT