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 
24 namespace 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) throw() = 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  */
68 std::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  */
92 bool
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  */
103 bool
104 NavGraphNodeConstraint::operator==(const std::string &name) const
105 {
106  return name_ == name;
107 }
108 
109 } // end of namespace fawkes
fawkes::NavGraphNodeConstraint::~NavGraphNodeConstraint
virtual ~NavGraphNodeConstraint()
Virtual empty destructor.
Definition: node_constraint.cpp:65
fawkes::NavGraphNodeConstraint::compute
virtual bool compute(void)
Perform compuations before graph search and to indicate re-planning.
Definition: node_constraint.cpp:97
fawkes::NavGraphNodeConstraint::name
std::string name()
Get name of constraint.
Definition: node_constraint.cpp:73
fawkes
fawkes::NavGraphNodeConstraint::name_
std::string name_
Definition: node_constraint.h:53
fawkes::NavGraphNodeConstraint::NavGraphNodeConstraint
NavGraphNodeConstraint(const std::string &name)
Constructor.
Definition: node_constraint.cpp:51
fawkes::NavGraphNodeConstraint::operator==
bool operator==(const std::string &name) const
Check if constraint matches name.
Definition: node_constraint.cpp:108