1 /**
2 * \brief A constraint determines a minimum or exact spacing required between
3 * two variables.
4 *
5 * Authors:
6 * Tim Dwyer <tgdwyer@gmail.com>
7 *
8 * Copyright (C) 2005 Authors
9 *
10 * Released under GNU LGPL. Read the file 'COPYING' for more information.
11 */
13 #include "constraint.h"
14 #include <cassert>
15 namespace vpsc {
16 Constraint::Constraint(Variable *left, Variable *right, double gap, bool equality)
17 : left(left),
18 right(right),
19 gap(gap),
20 timeStamp(0),
21 active(false),
22 visited(false),
23 equality(equality)
24 {
25 left->out.push_back(this);
26 right->in.push_back(this);
27 }
28 Constraint::~Constraint() {
29 Constraints::iterator i;
30 for(i=left->out.begin(); i!=left->out.end(); i++) {
31 if(*i==this) break;
32 }
33 left->out.erase(i);
34 for(i=right->in.begin(); i!=right->in.end(); i++) {
35 if(*i==this) break;
36 }
37 right->in.erase(i);
38 }
39 std::ostream& operator <<(std::ostream &os, const Constraint &c)
40 {
41 if(&c==NULL) {
42 os<<"NULL";
43 } else {
44 const char *type=c.equality?"=":"<=";
45 os<<*c.left<<"+"<<c.gap<<type<<*c.right<<"("<<c.slack()<<")"<<(c.active?"-active":"");
46 }
47 return os;
48 }
49 }