Doc-de: changes to notation manual

[lilypond.git] / lily / rest.cc

diff --git a/lily/rest.cc b/lily/rest.cc
index 0115e5176fbbf56921767051b0389b85ab84eee2..9057e45af1bd90deaf29c0419ac2a2b2233ee8a9 100644 (file)
--- a/lily/rest.cc
+++ b/lily/rest.cc
@@ -1,7 +1,7 @@
 /*
   This file is part of LilyPond, the GNU music typesetter.
 
-  Copyright (C) 1997--2011 Han-Wen Nienhuys <hanwen@xs4all.nl>
+  Copyright (C) 1997--2012 Han-Wen Nienhuys <hanwen@xs4all.nl>
 
   LilyPond is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -26,6 +26,7 @@
 #include "output-def.hh"
 #include "paper-score.hh"
 #include "staff-symbol-referencer.hh"
+#include "staff-symbol.hh"
 #include "stencil.hh"
 #include "grob.hh"
 
@@ -40,20 +41,54 @@ Rest::y_offset_callback (SCM smob)
   Real ss = Staff_symbol_referencer::staff_space (me);
 
   bool position_override = scm_is_number (me->get_property ("staff-position"));
-  Real amount = robust_scm2double (me->get_property ("staff-position"), 0)
-                * 0.5 * ss;
+  Real amount;
 
-  if (line_count % 2)
+  if (position_override)
     {
-      if (duration_log == 0 && line_count > 1)
+      amount
+        = robust_scm2double (me->get_property ("staff-position"), 0) * 0.5 * ss;
+
+      /*
+        semibreve rests are positioned one staff line off
+      */
+      if (duration_log == 0)
         amount += ss;
+
+      /*
+        trust the client on good positioning;
+        would be tempting to adjust position of rests longer than a quarter
+        to be properly aligned to staff lines,
+        but custom rest shapes may not need that sort of care.
+      */
     }
   else
-    amount += ss / 2;
+    {
+      int pos = 4 * get_grob_direction (me);
 
-  if (!position_override)
-    amount += 2 * ss * get_grob_direction (me);
+      /*
+        make a semibreve rest hang from the next line,
+        except for a single line staff
+      */
+      if (duration_log == 0 && line_count > 1)
+        pos += 2;
 
+      /*
+        make sure rest is aligned to a staff line
+      */
+      if (Grob *staff = Staff_symbol_referencer::get_staff_symbol (me))
+        {
+          std::vector<Real> linepos = Staff_symbol::line_positions (staff);
+          std::sort (linepos.begin (), linepos.end ());
+          std::vector<Real>::const_iterator it
+            = std::lower_bound (linepos.begin (), linepos.end (), pos);
+          if (it != linepos.end ())
+            {
+              pos = (int)ceil (*it);
+            }
+        }
+
+      amount = ss * 0.5 * pos;
+    }
 
   return scm_from_double (amount);
 }
@@ -78,22 +113,22 @@ Rest::calc_cross_staff (SCM smob)
   make this function easily usable in C++
 */
 string
-Rest::glyph_name (Grob *me, int balltype, string style, bool try_ledgers)
+Rest::glyph_name (Grob *me, int durlog, string style, bool try_ledgers)
 {
   bool is_ledgered = false;
-  if (try_ledgers && (balltype == -1 || balltype == 0 || balltype == 1))
+  if (try_ledgers && (durlog == -1 || durlog == 0 || durlog == 1))
     {
-      Real rad = Staff_symbol_referencer::staff_radius (me) * 2.0;
-      Real pos = Staff_symbol_referencer::get_position (me);
+      int const pos = int (Staff_symbol_referencer::get_position (me));
 
       /*
-        Figure out when the rest is far enough outside the staff. This
-        could bemore generic, but hey, we understand this even after
-        dinner.
+        half rests need ledger if not lying on a staff line,
+        whole rests need ledger if not hanging from a staff line,
+        breve rests need ledger if neither lying on nor hanging from a staff line
       */
-      is_ledgered |= (balltype == -1) && (pos <= -rad - 3 || pos >= +rad + 1);
-      is_ledgered |= (balltype == 0) && (pos >= +rad + 2 || pos < -rad);
-      is_ledgered |= (balltype == 1) && (pos <= -rad - 2 || pos > +rad);
+      if (-1 <= durlog && durlog <= 1)
+        is_ledgered = !Staff_symbol_referencer::on_staff_line (me, pos)
+                      && !(durlog == -1
+                           && Staff_symbol_referencer::on_staff_line (me, pos + 2));
     }
 
   string actual_style (style.c_str ());
@@ -113,11 +148,11 @@ Rest::glyph_name (Grob *me, int balltype, string style, bool try_ledgers)
         There are no 32th/64th/128th mensural/neomensural rests.  In
         these cases, revert back to default style.
       */
-      if (balltype > 4)
+      if (durlog > 4)
         actual_style = "";
     }
 
-  if ((style == "classical") && (balltype != 2))
+  if ((style == "classical") && (durlog != 2))
     {
       /*
         classical style: revert back to default style for any rest other
@@ -135,7 +170,7 @@ Rest::glyph_name (Grob *me, int balltype, string style, bool try_ledgers)
       actual_style = "";
     }
 
-  return ("rests." + to_string (balltype) + (is_ledgered ? "o" : "")
+  return ("rests." + to_string (durlog) + (is_ledgered ? "o" : "")
           + actual_style);
 }
 
@@ -143,19 +178,16 @@ MAKE_SCHEME_CALLBACK (Rest, print, 1);
 SCM
 Rest::brew_internal_stencil (Grob *me, bool ledgered)
 {
-  SCM balltype_scm = me->get_property ("duration-log");
-  if (!scm_is_number (balltype_scm))
+  SCM durlog_scm = me->get_property ("duration-log");
+  if (!scm_is_number (durlog_scm))
     return Stencil ().smobbed_copy ();
 
-  int balltype = scm_to_int (balltype_scm);
+  int durlog = scm_to_int (durlog_scm);
 
-  string style;
-  SCM style_scm = me->get_property ("style");
-  if (scm_is_symbol (style_scm))
-    style = ly_scm2string (scm_symbol_to_string (style_scm));
+  string style = robust_symbol2string (me->get_property ("style"), "default");
 
   Font_metric *fm = Font_interface::get_default_font (me);
-  string font_char = glyph_name (me, balltype, style, ledgered);
+  string font_char = glyph_name (me, durlog, style, ledgered);
   Stencil out = fm->find_by_name (font_char);
   if (out.is_empty ())
     me->warning (_f ("rest `%s' not found", font_char.c_str ()));
@@ -240,4 +272,3 @@ ADD_INTERFACE (Rest,
                "minimum-distance "
                "style "
               );
-