StateCostIntegralObjective.cpp
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34 
35 /* Author: Luis G. Torres */
36 
37 #include "ompl/base/objectives/StateCostIntegralObjective.h"
38 
40  bool enableMotionCostInterpolation)
41  : OptimizationObjective(si), interpolateMotionCost_(enableMotionCostInterpolation)
42 {
43  description_ = "State Cost Integral";
44 }
45 
47 {
48  return Cost(1.0);
49 }
50 
52 {
54  {
55  Cost totalCost = this->identityCost();
56 
57  int nd = si_->getStateSpace()->validSegmentCount(s1, s2);
58 
59  State *test1 = si_->cloneState(s1);
60  Cost prevStateCost = this->stateCost(test1);
61  if (nd > 1)
62  {
63  State *test2 = si_->allocState();
64  for (int j = 1; j < nd; ++j)
65  {
66  si_->getStateSpace()->interpolate(s1, s2, (double)j / (double)nd, test2);
67  Cost nextStateCost = this->stateCost(test2);
68  totalCost = Cost(totalCost.value() +
69  this->trapezoid(prevStateCost, nextStateCost, si_->distance(test1, test2)).value());
70  std::swap(test1, test2);
71  prevStateCost = nextStateCost;
72  }
73  si_->freeState(test2);
74  }
75 
76  // Lastly, add s2
77  totalCost = Cost(totalCost.value() +
78  this->trapezoid(prevStateCost, this->stateCost(s2), si_->distance(test1, s2)).value());
79 
80  si_->freeState(test1);
81 
82  return totalCost;
83  }
84 
85  return this->trapezoid(this->stateCost(s1), this->stateCost(s2), si_->distance(s1, s2));
86 }
87 
89 {
91 }
bool interpolateMotionCost_
If true, then motionCost() will more accurately compute the cost of a motion by taking small steps al...
std::string description_
The description of this optimization objective.
bool isMotionCostInterpolationEnabled() const
Returns whether this objective subdivides motions into smaller segments for more accurate motion cost...
Cost motionCost(const State *s1, const State *s2) const override
Compute the cost of a path segment from s1 to s2 (including endpoints)
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 trapezoid(Cost c1, Cost c2, double dist) const
Helper method which uses the trapezoidal rule to approximate the integral of the cost between two sta...
A shared pointer wrapper for ompl::base::SpaceInformation.
Definition of an abstract state.
Definition: State.h:49
StateCostIntegralObjective(const SpaceInformationPtr &si, bool enableMotionCostInterpolation=false)
If enableMotionCostInterpolation is set to true, then calls to motionCost() will divide the motion se...
Abstract definition of optimization objectives.
Cost stateCost(const State *s) const override
Returns a cost with a value of 1.
double value() const
The value of the cost.
Definition: Cost.h:56
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