lily/paper-system-scheme.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2008--2010 Han-Wen Nienhuys <hanwen@lilypond.org>
   5
   6
   7   LilyPond is free software: you can redistribute it and/or modify
   8   it under the terms of the GNU General Public License as published by
   9   the Free Software Foundation, either version 3 of the License, or
  10   (at your option) any later version.
  11
  12   LilyPond is distributed in the hope that it will be useful,
  13   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15   GNU General Public License for more details.
  16
  17   You should have received a copy of the GNU General Public License
  18   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "prob.hh"
  22
  23 #include "skyline-pair.hh"
  24
  25 LY_DEFINE (ly_paper_system_p, "ly:paper-system?",
  26           1, 0, 0, (SCM obj),
  27           "Is @var{obj} a C++ @code{Prob} object of type"
  28           " @code{paper-system}?")
  29 {
  30   return ly_prob_type_p (obj, ly_symbol2scm ("paper-system"));
  31 }
  32
  33 LY_DEFINE (ly_paper_system_minimum_distance, "ly:paper-system-minimum-distance",
  34            2, 0, 0, (SCM sys1, SCM sys2),
  35            "Measure the minimum distance between these two paper-systems,"
  36            " using their stored skylines if possible and falling back to"
  37            " their extents otherwise.")
  38 {
  39   Real ret = 0;
  40   Prob *p1 = unsmob_prob (sys1);
  41   Prob *p2 = unsmob_prob (sys2);
  42   Skyline_pair *sky1 = Skyline_pair::unsmob (p1->get_property ("vertical-skylines"));
  43   Skyline_pair *sky2 = Skyline_pair::unsmob (p2->get_property ("vertical-skylines"));
  44
  45   if (sky1 && sky2)
  46     ret = (*sky1)[DOWN].distance ((*sky2)[UP]);
  47   else
  48     {
  49       Stencil *s1 = unsmob_stencil (p1->get_property ("stencil"));
  50       Stencil *s2 = unsmob_stencil (p2->get_property ("stencil"));
  51       Interval iv1 = s1->extent (Y_AXIS);
  52       Interval iv2 = s2->extent (Y_AXIS);
  53       ret = iv2[UP] - iv1[DOWN];
  54     }
  55   return scm_from_double (ret);
  56 }