final_time_cost.h

/*
 * Copyright (c) 2019, The Regents of the University of California (Regents).
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *    1. Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *
 *    2. Redistributions in binary form must reproduce the above
 *       copyright notice, this list of conditions and the following
 *       disclaimer in the documentation and/or other materials provided
 *       with the distribution.
 *
 *    3. Neither the name of the copyright holder nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS AS IS
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * Please contact the author(s) of this library if you have any questions.
 * Authors: David Fridovich-Keil   ( dfk@eecs.berkeley.edu )
 */

///////////////////////////////////////////////////////////////////////////////
//
// Class for applying a given cost only after a fixed time.
//
///////////////////////////////////////////////////////////////////////////////

#ifndef ILQGAMES_COST_FINAL_TIME_COST_H
#define ILQGAMES_COST_FINAL_TIME_COST_H

#include <ilqgames/cost/cost.h>
#include <ilqgames/utils/types.h>

#include <glog/logging.h>
#include <memory>
#include <string>

namespace ilqgames {

class FinalTimeCost : public Cost {
 public:
  ~FinalTimeCost() {}
  FinalTimeCost(const std::shared_ptr<const Cost>& cost, Time threshold_time,
                const std::string& name = "")
      : Cost(0.0, name), cost_(cost), threshold_time_(threshold_time) {
    CHECK_NOTNULL(cost.get());
  }

  // Evaluate this cost at the current time and input.
  float Evaluate(Time t, const VectorXf& input) const {
    return (t >= initial_time_ + threshold_time_) ? cost_->Evaluate(t, input)
                                                  : 0.0;
  }

  // Quadraticize this cost at the given time and input, and add to the running
  // sum of gradients and Hessians.
  void Quadraticize(Time t, const VectorXf& input, MatrixXf* hess,
                    VectorXf* grad) const {
    if (t < initial_time_ + threshold_time_) return;
    cost_->Quadraticize(t, input, hess, grad);
  }

 private:
  // Cost function.
  const std::shared_ptr<const Cost> cost_;

  // Time threshold relative to initial time after which to apply cost.
  const Time threshold_time_;
};  //\class Cost

}  // namespace ilqgames

#endif