PlannerTerminationCondition.cpp

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/* Author: Ioan Sucan */

#include "ompl/base/PlannerTerminationCondition.h"
#include "ompl/util/Time.h"
#include <functional>
#include <thread>
#include <utility>

namespace ompl
{
    namespace base
    {

        class PlannerTerminationCondition::PlannerTerminationConditionImpl
        {
        public:
            PlannerTerminationConditionImpl(const PlannerTerminationConditionFn &fn, double period) :
            fn_(fn),
            period_(period),
            terminate_(false),
            thread_(nullptr),
            evalValue_(false),
            signalThreadStop_(false)
            {
                if (period_ > 0.0)
                    startEvalThread();
            }

            ~PlannerTerminationConditionImpl()
            {
                stopEvalThread();
            }

            bool eval() const
            {
                if (terminate_)
                    return true;
                if (period_ > 0.0)
                    return evalValue_;
                return fn_();
            }

            void terminate() const
            {
                // it is ok to have unprotected write here
                terminate_ = true;
            }

        private:

            void startEvalThread()
            {
                if (!thread_)
                {
                    signalThreadStop_ = false;
                    evalValue_ = false;
                    thread_ = new std::thread(std::bind(&PlannerTerminationConditionImpl::periodicEval, this));
                }
            }

            void stopEvalThread()
            {
                signalThreadStop_ = true;
                if (thread_)
                {
                    thread_->join();
                    delete thread_;
                    thread_ = nullptr;
                }
            }

            void periodicEval()
            {
                // we want to check for termination at least once every ms;
                // even though we may evaluate the condition itself more rarely

                unsigned int count = 1;
                time::duration s = time::seconds(period_);
                if (period_ > 0.001)
                {
                    count = 0.5 + period_ / 0.001;
                    s = time::seconds(period_ / (double) count);
                }

                while (!terminate_ && !signalThreadStop_)
                {
                    evalValue_ = fn_();
                    for (unsigned int i = 0 ; i < count ; ++i)
                    {
                        if (terminate_ || signalThreadStop_)
                            break;
                        std::this_thread::sleep_for(s);
                    }
                }
            }

            PlannerTerminationConditionFn fn_;

            double                        period_;

            mutable bool                  terminate_;

            std::thread                  *thread_;

            bool                          evalValue_;

            bool                          signalThreadStop_;
        };

    }
}

ompl::base::PlannerTerminationCondition::PlannerTerminationCondition(const PlannerTerminationConditionFn &fn) :
impl_(new PlannerTerminationConditionImpl(fn, -1.0))
{
}

ompl::base::PlannerTerminationCondition::PlannerTerminationCondition(const PlannerTerminationConditionFn &fn, double period) :
impl_(new PlannerTerminationConditionImpl(fn, period))
{
}

void ompl::base::PlannerTerminationCondition::terminate() const
{
    impl_->terminate();
}

bool ompl::base::PlannerTerminationCondition::eval() const
{
    return impl_->eval();
}

ompl::base::PlannerTerminationCondition ompl::base::plannerNonTerminatingCondition()
{
    return PlannerTerminationCondition([] { return false; });
}

ompl::base::PlannerTerminationCondition ompl::base::plannerAlwaysTerminatingCondition()
{
    return PlannerTerminationCondition([] { return true; });
}

namespace ompl
{
    namespace base
    {
        static bool plannerOrTerminationConditionAux(const PlannerTerminationCondition &c1, const PlannerTerminationCondition &c2)
        {
            return c1() || c2();
        }

        static bool plannerAndTerminationConditionAux(const PlannerTerminationCondition &c1, const PlannerTerminationCondition &c2)
        {
            return c1() && c2();
        }

        // return true if a certain point in time has passed
        static bool timePassed(const time::point &endTime)
        {
            return time::now() > endTime;
        }
    }
}

ompl::base::PlannerTerminationCondition ompl::base::plannerOrTerminationCondition(const PlannerTerminationCondition &c1, const PlannerTerminationCondition &c2)
{
    return PlannerTerminationCondition(std::bind(&plannerOrTerminationConditionAux, c1, c2));
}

ompl::base::PlannerTerminationCondition ompl::base::plannerAndTerminationCondition(const PlannerTerminationCondition &c1, const PlannerTerminationCondition &c2)
{
    return PlannerTerminationCondition(std::bind(&plannerAndTerminationConditionAux, c1, c2));
}

ompl::base::PlannerTerminationCondition ompl::base::timedPlannerTerminationCondition(double duration)
{
    return timedPlannerTerminationCondition(time::seconds(duration));
}

ompl::base::PlannerTerminationCondition ompl::base::timedPlannerTerminationCondition(time::duration duration)
{
    return PlannerTerminationCondition(std::bind(&timePassed, time::now() + duration));
}

ompl::base::PlannerTerminationCondition ompl::base::timedPlannerTerminationCondition(double duration, double interval)
{
    if (interval > duration)
        interval = duration;
    return PlannerTerminationCondition(std::bind(&timePassed, time::now() + time::seconds(duration)), interval);
}

ompl::base::PlannerTerminationCondition ompl::base::exactSolnPlannerTerminationCondition(ompl::base::ProblemDefinitionPtr pdef)
{
    return PlannerTerminationCondition(std::bind(&ProblemDefinition::hasExactSolution, pdef));
}

namespace ompl
{
    namespace base
    {
        IterationTerminationCondition::IterationTerminationCondition(unsigned int numIterations)
          : maxCalls_(numIterations),
            timesCalled_(0u)
        {
        }

        bool IterationTerminationCondition::eval()
        {
            ++timesCalled_;

            return (timesCalled_ > maxCalls_);
        }

        void IterationTerminationCondition::reset()
        {
            timesCalled_ = 0u;
        }

        IterationTerminationCondition::operator PlannerTerminationCondition()
        {
            return PlannerTerminationCondition( std::bind(&IterationTerminationCondition::eval, this) );
        }
    }
}