MinimaxObjective.cpp
1 /*********************************************************************
2 * Software License Agreement (BSD License)
3 *
4 * Copyright (c) 2010, Rice University
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * * Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * * Redistributions in binary form must reproduce the above
14 * copyright notice, this list of conditions and the following
15 * disclaimer in the documentation and/or other materials provided
16 * with the distribution.
17 * * Neither the name of the Rice University nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
29 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
31 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32 * POSSIBILITY OF SUCH DAMAGE.
33 *********************************************************************/
34 
35 /* Author: Luis G. Torres */
36 
37 #include "ompl/base/objectives/MinimaxObjective.h"
38 
39 ompl::base::MinimaxObjective::MinimaxObjective(const SpaceInformationPtr &si) : OptimizationObjective(si)
40 {
41 }
42 
44 {
45  return Cost(1.0);
46 }
47 
49 {
50  Cost worstCost = this->identityCost();
51 
52  int nd = si_->getStateSpace()->validSegmentCount(s1, s2);
53 
54  if (nd > 1)
55  {
56  State *test = si_->allocState();
57  for (int j = 1; j < nd; ++j)
58  {
59  si_->getStateSpace()->interpolate(s1, s2, (double)j / (double)nd, test);
60  Cost testStateCost = this->stateCost(test);
61  if (this->isCostBetterThan(worstCost, testStateCost))
62  worstCost = testStateCost;
63  }
64  si_->freeState(test);
65  }
66 
67  // Lastly, check s2
68  Cost lastCost = this->stateCost(s2);
69  if (this->isCostBetterThan(worstCost, lastCost))
70  worstCost = lastCost;
71 
72  return worstCost;
73 }
74 
76 {
77  return this->isCostBetterThan(c1, c2) ? c2 : c1;
78 }
Cost combineCosts(Cost c1, Cost c2) const override
Since we&#39;re only concerned about the "worst" state cost in the path, combining two costs just returns...
Cost motionCost(const State *s1, const State *s2) const override
Interpolates between s1 and s2 to check for state costs along the motion between the two states...
Definition of an abstract state.
Definition: State.h:49
Cost stateCost(const State *s) const override
Returns a cost with a value of 1.
Definition of a cost value. Can represent the cost of a motion or the cost of a state.
Definition: Cost.h:47