Fawkes API Fawkes Development Version
node_constraint.cpp
1/***************************************************************************
2 * node_constraint.cpp - base class for nod constraints
3 *
4 * Created: Sun Mar 02 10:47:35 2014
5 * Copyright 2014 Sebastian Reuter
6 * 2014 Tim Niemueller
7 ****************************************************************************/
8
9/* This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU Library General Public License for more details.
18 *
19 * Read the full text in the LICENSE.GPL file in the doc directory.
20 */
21
22#include <navgraph/constraints/node_constraint.h>
23
24namespace fawkes {
25
26/** @class NavGraphNodeConstraint <navgraph/constraints/node_constraint.h>
27 * Constraint that can be queried to check if a node is blocked.
28 * @author Sebastian Reuter
29 * @author Tim Niemueller
30 *
31 * @fn bool NavGraphNodeConstraint::blocks(fawkes::NavGraphNode &node) noexcept = 0
32 * Check if constraint blocks a node.
33 * This method must be implemented by constraint classes. It is called
34 * to determine if a node should be considered blocked and therefore
35 * cannot be expanded during path search. Note that the method may not
36 * throw an exception. Handle this internally appropriately.
37 * @param node node to check for expansion
38 * @return true if the node should be considered blocked, false otherwise
39 *
40 * @var std::string NavGraphNodeConstraint::name_
41 * Name of constraint.
42 */
43
44/** Constructor.
45 * @param name name of node constraint
46 */
48{
49 name_ = name;
50}
51
52/** Constructor.
53 * @param name name of node constraint
54 */
56{
57 name_ = name;
58}
59
60/** Virtual empty destructor. */
62{
63}
64
65/** Get name of constraint.
66 * @return name of constraint
67 */
68std::string
70{
71 return name_;
72}
73
74/** Perform compuations before graph search and to indicate re-planning.
75 * The compute method is called on all constraints just before a path
76 * search is performed and to check if re-planning should be tried.
77 *
78 * It can be used for example to cache results for the coming search
79 * run. The search guarantees that for each complete search run
80 * compute() is called once and only once and that no two search runs
81 * overlap, i.e., compute() will not be called while another search is
82 * still running.
83 *
84 * Constraints must indicate whether any change has occured during
85 * computation or since the last compute() call through the return
86 * value. This is used to determine if re-planning should be
87 * attempted.
88 *
89 * @return true if a change has occured during computation or since
90 * the last call, false otherwise
91 */
92bool
94{
95 return false;
96}
97
98/** Check if constraint matches name.
99 * @param name name string to compare this constraints name to
100 * @return true if the given name is the same as this constraint's name,
101 * false otherwise
102 */
103bool
104NavGraphNodeConstraint::operator==(const std::string &name) const
105{
106 return name_ == name;
107}
108
109} // end of namespace fawkes
std::string name_
Name of constraint.
virtual ~NavGraphNodeConstraint()
Virtual empty destructor.
virtual bool compute(void) noexcept
Perform compuations before graph search and to indicate re-planning.
bool operator==(const std::string &name) const
Check if constraint matches name.
NavGraphNodeConstraint(const std::string &name)
Constructor.
std::string name()
Get name of constraint.
Fawkes library namespace.