MinimaxObjective.cpp
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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  if (this->isCostBetterThan(c1, c2))
78  return c2;
79  else
80  return c1;
81 }
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...
virtual Cost identityCost() const
Get the identity cost value. The identity cost value is the cost c_i such that, for all costs c...
Cost stateCost(const State *s) const override
Returns a cost with a value of 1.
Definition of an abstract state.
Definition: State.h:49
Cost stateCost(const State *s) const override
Returns a cost with a value of 1.
virtual bool isCostBetterThan(Cost c1, Cost c2) const
Check whether the the cost c1 is considered better than the cost c2. By default, this returns true if...
SpaceInformationPtr si_
The space information for this objective.
Definition of a cost value. Can represent the cost of a motion or the cost of a state.
Definition: Cost.h:47