polyline2.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 )
 */

///////////////////////////////////////////////////////////////////////////////
//
// Polyline2 class for piecewise linear paths in 2D.
//
///////////////////////////////////////////////////////////////////////////////

#ifndef ILQGAMES_GEOMETRY_POLYLINE2_H
#define ILQGAMES_GEOMETRY_POLYLINE2_H

#include <ilqgames/geometry/line_segment2.h>
#include <ilqgames/utils/types.h>

#include <glog/logging.h>
#include <math.h>

namespace ilqgames {

class Polyline2 {
 public:
  // Construct from a list of points. This list must contain at least 2 points!
  Polyline2(const PointList2& points);
  ~Polyline2() {}

  // Add a new point to the end of the polyline.
  void AddPoint(const Point2& point);

  // Compute length.
  float Length() const { return length_; }

  // Find closest point on this line segment to a given point, and optionally
  // the line segment that point belongs to (and flag for whether it is a
  // vertex), and the signed squared distance, where right is positive.
  Point2 ClosestPoint(const Point2& query, bool* is_vertex = nullptr,
                      LineSegment2* segment = nullptr,
                      float* signed_squared_distance = nullptr,
                      bool* is_endpoint = nullptr) const;

  // Find the point the given distance from the start of the polyline.
  // Optionally returns whether this is a vertex and the line segment which the
  // point belongs to.
  Point2 PointAt(float route_pos, bool* is_vertex = nullptr,
                 LineSegment2* segment = nullptr,
                 bool* is_endpoint = nullptr) const;

  // Access line segments.
  const std::vector<LineSegment2>& Segments() const { return segments_; }

 private:
  std::vector<LineSegment2> segments_;
  std::vector<float> cumulative_lengths_;
  float length_;
};  // struct Polyline2

}  // namespace ilqgames

#endif