ObstacleBasedValidStateSampler.cpp
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34 
35 /* Author: Ioan Sucan */
36 
37 #include "ompl/base/samplers/ObstacleBasedValidStateSampler.h"
38 #include "ompl/base/SpaceInformation.h"
39 
41  : ValidStateSampler(si), sampler_(si->allocStateSampler())
42 {
43  name_ = "obstacle_based";
44 }
45 
47 {
48  // find invalid state
49  unsigned int attempts = 0;
50  bool valid = true;
51  do
52  {
53  sampler_->sampleUniform(state);
54  valid = si_->isValid(state);
55  ++attempts;
56  } while (valid && attempts < attempts_);
57  if (valid)
58  return false;
59 
60  // find a valid state
61  State *temp = si_->allocState();
62  attempts = 0;
63  do
64  {
65  sampler_->sampleUniform(temp);
66  valid = si_->isValid(temp);
67  ++attempts;
68  } while (!valid && attempts < attempts_);
69 
70  // keep the last valid state, before collision
71  if (valid)
72  {
73  std::pair<State *, double> fail(state, 0.0);
74  si_->checkMotion(temp, state, fail);
75  }
76 
77  si_->freeState(temp);
78 
79  return valid;
80 }
81 
82 bool ompl::base::ObstacleBasedValidStateSampler::sampleNear(State *state, const State *near, const double distance)
83 {
84  // find invalid state nearby
85  unsigned int attempts = 0;
86  bool valid = true;
87  do
88  {
89  sampler_->sampleUniformNear(state, near, distance);
90  valid = si_->isValid(state);
91  ++attempts;
92  } while (valid && attempts < attempts_);
93  if (valid)
94  return false;
95 
96  // find a valid state
97  State *temp = si_->allocState();
98  attempts = 0;
99  do
100  {
101  sampler_->sampleUniform(temp);
102  valid = si_->isValid(temp);
103  ++attempts;
104  } while (!valid && attempts < attempts_);
105 
106  // keep the last valid state, before collision
107  if (valid)
108  {
109  std::pair<State *, double> fail(state, 0.0);
110  si_->checkMotion(temp, state, fail);
111  }
112 
113  si_->freeState(temp);
114 
115  return valid;
116 }
void freeState(State *state) const
Free the memory of a state.
const SpaceInformation * si_
The state space this sampler samples.
bool isValid(const State *state) const
Check if a given state is valid or not.
State * allocState() const
Allocate memory for a state.
ObstacleBasedValidStateSampler(const SpaceInformation *si)
Constructor.
bool sampleNear(State *state, const State *near, const double distance) override
Sample a state near another, within specified distance. Return false, in case of failure.
Abstract definition of a state sampler.
The base class for space information. This contains all the information about the space planning is d...
unsigned int attempts_
Number of attempts to find a valid sample.
Definition of an abstract state.
Definition: State.h:49
StateSamplerPtr sampler_
The sampler to build upon.
bool checkMotion(const State *s1, const State *s2, std::pair< State *, double > &lastValid) const
Incrementally check if the path between two motions is valid. Also compute the last state that was va...
bool sample(State *state) override
Sample a state. Return false in case of failure.
std::string name_
The name of the sampler.