/*
- simple-spacer-scheme.cc -- implement Simple_spacer
+ This file is part of LilyPond, the GNU music typesetter.
- source file of the GNU LilyPond music typesetter
+ Copyright (C) 2005--2015 Han-Wen Nienhuys <hanwen@xs4all.nl>
- (c) 2005--2007 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
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ LilyPond is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
*/
#include <cstdio>
#include "simple-spacer.hh"
LY_DEFINE (ly_solve_spring_rod_problem, "ly:solve-spring-rod-problem",
- 4, 1, 0, (SCM springs, SCM rods, SCM length, SCM ragged),
- "Solve a spring and rod problem for @var{count} objects, that "
- "are connected by @var{count-1} springs, and an arbitrary number of rods "
- "Springs have the format (ideal, hooke) and rods (idx1, idx2, distance) "
- "@var{length} is a number, @var{ragged} a boolean "
- "Return: a list containing the force (positive for stretching, "
- "negative for compressing and #f for non-satisfied constraints) "
- "followed by the @var{spring-count}+1 positions of the objects. ")
+ 4, 1, 0, (SCM springs, SCM rods, SCM length, SCM ragged),
+ "Solve a spring and rod problem for @var{count} objects, that"
+ " are connected by @var{count}-1 @var{springs}, and an arbitrary"
+ " number of @var{rods}. @var{count} is implicitly given by"
+ " @var{springs} and @var{rods}. The @var{springs} argument has"
+ " the format @code{(ideal, inverse_hook)} and @var{rods} is of"
+ " the form @code{(idx1, idx2, distance)}.\n"
+ "\n"
+ "@var{length} is a number, @var{ragged} a boolean.\n"
+ "\n"
+ "The function returns a list containing the force (positive for"
+ " stretching, negative for compressing and @code{#f} for"
+ " non-satisfied constraints) followed by @var{spring-count}+1"
+ " positions of the objects.")
{
int len = scm_ilength (springs);
if (len == 0)
return scm_list_2 (scm_from_double (0.0), scm_from_double (0.0));
SCM_ASSERT_TYPE (len >= 0, springs, SCM_ARG1, __FUNCTION__, "list of springs");
- SCM_ASSERT_TYPE (scm_ilength (rods) > 0, rods, SCM_ARG1, __FUNCTION__, "list of rods");
- LY_ASSERT_TYPE(scm_is_number, length, 3);
+ SCM_ASSERT_TYPE (scm_ilength (rods) > 0, rods, SCM_ARG1, __FUNCTION__, "list of rods");
+ LY_ASSERT_TYPE (scm_is_number, length, 3);
- bool is_ragged = ragged == SCM_BOOL_T;
+ bool is_ragged = to_boolean (ragged);
Simple_spacer spacer;
for (SCM s = springs; scm_is_pair (s); s = scm_cdr (s))
{
Real ideal = scm_to_double (scm_caar (s));
- Real hooke = scm_to_double (scm_cadar (s));
+ Real inv_hooke = scm_to_double (scm_cadar (s));
+
+ Spring sp (ideal, 0.0);
+ sp.set_inverse_compress_strength (inv_hooke);
+ sp.set_inverse_stretch_strength (inv_hooke);
- spacer.add_spring (ideal, 1 / hooke);
+ spacer.add_spring (sp);
}
for (SCM s = rods; scm_is_pair (s); s = scm_cdr (s))