Re: New partcombineUp and partcombineDown functions (issue 4514042)

[bordage . bertrand]

Reviewers: J_lowe, dan_faithful.be,

Message:
I updated the patch and added a regtest.
Dan, I don't have time for now to rewrite the whole part combiner. Do
you want to do it ? If so, I can help you (at my level).

Bertrand

Description:
New partcombineUp and partcombineDown functions

Fix issue 1321

Please review this at http://codereview.appspot.com/4514042/

Affected files:
  A input/regression/part-combine-3voices.ly
  M lily/part-combine-iterator.cc
  M ly/music-functions-init.ly
  M scm/part-combiner.scm


Index: input/regression/part-combine-3voices.ly
diff --git a/input/regression/part-combine-3voices.ly  
b/input/regression/part-combine-3voices.ly
new file mode 100644
index  
0000000000000000000000000000000000000000..8dcb00966b4eec2b882b4562d9da3e49d79c96ab
--- /dev/null
+++ b/input/regression/part-combine-3voices.ly
@@ -0,0 +1,18 @@
+\version "2.15.10"
+
+\header {
+  texidoc ="It is possible to use the part combiner for three
+       voices with \\partcombineUp and \\partcombineDown."
+}
+
+
+soprano = { d''2 f'' g'' }
+alto = { a' c''4 d'' e''2 }
+tenor = { f'2 a'4 b' c''2 }
+basso = { d'4 e' f' g' g'2 }
+
+\new Staff << \partcombineUp \soprano \alto \\ \basso >>
+
+\new Staff << \soprano \\ \partcombineDown \tenor \basso >>
+
+
Index: lily/part-combine-iterator.cc
diff --git a/lily/part-combine-iterator.cc b/lily/part-combine-iterator.cc
index  
4583d221f646ef9bcdc801dd46c4674366795fb3..9ab0495ae14ce909838c5498e5421d28590fd5bf  
100644
--- a/lily/part-combine-iterator.cc
+++ b/lily/part-combine-iterator.cc
@@ -65,6 +65,11 @@ private:
   Moment start_moment_;

   SCM split_list_;
+  SCM direction_;
+  SCM directionOne_;
+  SCM directionTwo_;
+  SCM horizontalShiftOne_;
+  SCM horizontalShiftTwo_;

   Stream_event *unisono_event_;
   Stream_event *solo_one_event_;
@@ -133,6 +138,11 @@ Part_combine_iterator::Part_combine_iterator ()
   first_iter_ = 0;
   second_iter_ = 0;
   split_list_ = SCM_EOL;
+  direction_ = SCM_BOOL_F;
+  directionOne_ = scm_from_int (1);
+  directionTwo_ = scm_from_int (-1);
+  horizontalShiftOne_ = scm_from_int (0);
+  horizontalShiftTwo_ = scm_from_int (1);
   state_ = APART;
   playing_state_ = APART;
   last_playing_ = APART;
@@ -349,6 +359,17 @@ Part_combine_iterator::construct_children ()
 {
   start_moment_ = get_outlet ()->now_mom ();
   split_list_ = get_music ()->get_property ("split-list");
+  direction_ = get_music ()->get_property ("direction");
+  if (is_direction (direction_))
+    {
+      directionOne_ = direction_;
+      directionTwo_ = direction_;
+      if (scm_is_true (scm_negative_p (direction_)))
+        {
+          horizontalShiftOne_ = scm_from_int (1);
+          horizontalShiftTwo_ = scm_from_int (0);
+        }
+    }

   Context *c = get_outlet ();

@@ -369,6 +390,8 @@ Part_combine_iterator::construct_children ()
   Context *two = handles_[CONTEXT_TWO].get_context ();
   set_context (two);
   second_iter_ = unsmob_iterator (get_iterator (unsmob_music (scm_cadr  
(lst))));
+  Context *shared = handles_[CONTEXT_SHARED].get_context ();
+  set_context (shared);

   /* Mimic all settings of voiceOne/voiceTwo for the two separate  
voices...*/
   /* FIXME: Is there any way to use the definition of \voiceOne/\voiceTwo
@@ -391,16 +414,20 @@ Part_combine_iterator::construct_children ()
     {
       SCM sym = ly_symbol2scm (*p);
       execute_pushpop_property (one, sym,
-                                ly_symbol2scm ("direction"), scm_from_int  
(1));
+                                ly_symbol2scm ("direction"),  
directionOne_);

       execute_pushpop_property (two, sym,
-                                ly_symbol2scm ("direction"), scm_from_int  
(-1));
+                                ly_symbol2scm ("direction"),  
directionTwo_);
+
+      if (scm_is_number (direction_))
+        execute_pushpop_property (shared, sym,
+                                 ly_symbol2scm ("direction"), direction_);
     }
   /* Handle horizontal shifts for crossing notes */
   execute_pushpop_property (one, ly_symbol2scm ("NoteColumn"),
-                            ly_symbol2scm ("horizontal-shift"),  
scm_from_int (0));
+                            ly_symbol2scm ("horizontal-shift"),  
horizontalShiftOne_);
   execute_pushpop_property (two, ly_symbol2scm ("NoteColumn"),
-                            ly_symbol2scm ("horizontal-shift"),  
scm_from_int (1));
+                            ly_symbol2scm ("horizontal-shift"),  
horizontalShiftTwo_);
   /* Also handle MultiMeasureRest positions for voice 1/2 */
   execute_pushpop_property (one, ly_symbol2scm ("MultiMeasureRest"),
                             ly_symbol2scm ("staff-position"), scm_from_int  
(4));
Index: ly/music-functions-init.ly
diff --git a/ly/music-functions-init.ly b/ly/music-functions-init.ly
index  
b3a009860753c54d7ab7549617ab4ba6f32d3ae5..1419daa808f7ebf5e65f33cb9116b940d1fdda67  
100644
--- a/ly/music-functions-init.ly
+++ b/ly/music-functions-init.ly
@@ -767,7 +767,21 @@ partcombine =
    (_i "Take the music in @var{part1} and @var{part2} and typeset so
 that they share a staff.")
    (make-part-combine-music parser
-                            (list part1 part2)))
+                            (list part1 part2) #f))
+
+partcombineUp =
+#(define-music-function (parser location part1 part2) (ly:music? ly:music?)
+   (_i "Take the music in @var{part1} and @var{part2} and typeset so
+that they share a staff with stems directed upward.")
+   (make-part-combine-music parser
+                            (list part1 part2) UP))
+
+partcombineDown =
+#(define-music-function (parser location part1 part2) (ly:music? ly:music?)
+   (_i "Take the music in @var{part1} and @var{part2} and typeset so
+that they share a staff with stems directed downward.")
+   (make-part-combine-music parser
+                            (list part1 part2) DOWN))

 partcombineForce =
 #(define-music-function (location parser type once) (symbol-or-boolean?  
boolean?)
Index: scm/part-combiner.scm
diff --git a/scm/part-combiner.scm b/scm/part-combiner.scm
index  
c492701c9142087bb6c44ac65deabf1a41d0a224..61fbf95f50587f79700f96371a7e3bd087bb1fe5  
100644
--- a/scm/part-combiner.scm
+++ b/scm/part-combiner.scm
@@ -243,7 +243,7 @@ LilyPond version 2.8 and earlier."
     (ly:interpret-music-expression (make-non-relative-music music) global)
     context-list))

-(define-public (make-part-combine-music parser music-list)
+(define-public (make-part-combine-music parser music-list direction)
   (let* ((m (make-music 'PartCombineMusic))
 	 (m1 (make-non-relative-music (context-spec-music (first  
music-list) 'Voice "one")))
 	 (m2  (make-non-relative-music  (context-spec-music (second  
music-list) 'Voice "two")))
@@ -252,6 +252,7 @@ LilyPond version 2.8 and earlier."
         (evs1 (recording-group-emulate m1 listener)))

     (set! (ly:music-property m 'elements) (list m1 m2))
+    (set! (ly:music-property m 'direction) direction)
     (set! (ly:music-property m 'split-list)
          (if (and (assoc "one" evs1) (assoc "two" evs2))
              (determine-split-list (reverse! (assoc-get "one" evs1) '())