polyline.h

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#ifndef POLYLINE_H
#define POLYLINE_H
#include "wcpplib/geometry/vec.h"
#include "wcpplib/geometry/straight.h"
#include "wcpplib/geometry/plane.h"
 
/*
Copyright (c) 2000 Igor B. Smirnov
 
The file can be used, copied, modified, and distributed
according to the terms of GNU Lesser General Public License version 2.1
as published by the Free Software Foundation,
and provided that the above copyright notice, this permission notice,
and notices about any modifications of the original text
appear in all copies and in supporting documentation.
The file is provided "as is" without express or implied warranty.
*/
 
namespace Heed {
 
/// Polyline.
 
class polyline : public absref {
 protected:
  int qpt;
  point* pt;
  int qsl;
  straight* sl;
 
 public:
  int Gqpt() const { return qpt; }
  point Gpt(int n) const {  
    if (n >= qpt) {
      mcerr << "error in polyline:Gpt(int n): n>qpt: n=" << n << " qpt=" << qpt
            << '\n';
      spexit(mcerr);
    }
    return pt[n];
  }
  int Gqsl() const { return qsl; }
  straight Gsl(int n) const {
    if (n >= qsl) {
      mcerr << "error in polyline:Gpt(int n): n>qsl: n=" << n << " qsl=" << qsl
            << '\n';
      spexit(mcerr);
    }
    return sl[n];
  }
 
 protected:
  absref** aref;
  virtual absref_transmit get_components() override;
 
 public:
  /// Return whether a point is inside.
  /// 0 point is not in
  /// 1 point coincides with an edge
  /// 2 point is inside an interval
  int check_point_in(const point& fpt, vfloat prec) const;
 
  /// If straight line goes exactly by segment of polyline,
  /// the fuction gives two end points of adjacent segments and the
  /// segment itself.
  /// If one of the points is common, it is given several times.
  /// For example, if line crosses break point the point is given two times.
  int cross(const straight& fsl, point* pc, int& qpc, polyline* pl, int& qpl,
            vfloat prec) const;
  /// Distance between two intervals.
  vfloat dist_two_inter(polyline& pl, vfloat prec) const;
  vfloat distance(const point& fpt) const;
  /// Distance between two points.
  vfloat distance(const point& fpt, point& cpt) const;
 
 protected:
  void polyline_init(const point* fpt, int fqpt);
  void polyline_del() {
    if (pt) {
      delete[] pt;
      pt = NULL;
    }
    if (sl) {
      delete[] sl;
      sl = NULL;
    }
    if (aref) {
      delete[] aref;
      aref = NULL;
    }
  }
 
 public:
  polyline() {
    point ptl;
    polyline_init(&ptl, 0);
  }
 
  polyline(polyline& pl);
  polyline(const polyline& pl);
 
  polyline(const point* fpt, int fqpt);
  polyline(const point& fpt1, const point& fpt2);  // interval
 
  polyline& operator=(const polyline& fpl);
 
  ~polyline() { polyline_del(); }
  friend int plane::cross(const polyline& pll, point* crpt, int& qcrpt,
                          polyline* crpll, int& qcrpll, vfloat prec) const;
  friend std::ostream& operator<<(std::ostream& file, const polyline& p);
};
 
/// Draws straight line via 4 intervals.
/// Returns 1 if line is drawn and 0 otherwise.
int cross4pllines(const polyline pl[4], vfloat precision, straight& sl,
                  point ptc[4][2]);
 
std::ostream& operator<<(std::ostream& file, const polyline& p);
 
/// Polyline in plane.
 
class polyline_pl : public polyline {
 protected:
  plane pn;
 
 public:
  plane Gpn() const { return pn; }
 
 protected:
  static absref(absref::*aref_pl);
  virtual absref_transmit get_components() override;
 
 public:
  polyline_pl() : polyline(), pn() { ; }
  polyline_pl(const polyline_pl& pl) : polyline(pl), pn(pl.pn) { ; }
  polyline_pl(const plane& fpn, const point* fpt, int fqpt)
      : polyline(fpt, fqpt), pn(fpn) {}
  polyline_pl(polyline& pl);
  polyline_pl(const polyline& pl);
 
  polyline_pl& operator=(const polyline_pl& fpl);
  friend std::ostream& operator<<(std::ostream& file, const polyline_pl& p);
};
 
std::ostream& operator<<(std::ostream& file, const polyline_pl& p);
 
/// Polygon in plane.
 
class polygon : public polyline_pl {
 public:
  int s_convex;
  int check_point_in(const point& fpt, vfloat prec) const;
  //            0 point is not in
  //            1 point coincides with an edge
  //            2 point is inside an interval of border
  //            3 point is inside body
  point cross(const straight& fsl, vfloat prec) const;
  // if no cross, returns vecerror=1.
 
  int range(const point& fpt, const vec& dir, vfloat& rng, point& fptenr,
            vfloat prec) const;
  polygon& operator=(const polygon& fpl);
  polygon() : polyline_pl(), s_convex(0) {}
  polygon(const polygon& plg) : polyline_pl((polyline_pl)plg) {
    s_convex = plg.s_convex;
  }
  polygon(const polyline_pl& fpl, int fs_convex)
      : polyline_pl(fpl), s_convex(fs_convex) {
    if (fpl.Gqpt() < 4 || fpl.Gpt(0) != fpl.Gpt(qpt - 1)) {  
      mcerr << "ERROR in polygon::polygon(polyline_pl& fpl, int fs_convex)\n";
      mcerr << "fpl.Gqpt() < 4 || fpl.Gpt(0)!=fpl.Gpt(qpt-1)\n";
      spexit(mcerr);
    }
  }
  polygon(const straight* fsl, int fqsl, vfloat prec);
  // Prec is used to find crossing points of straight lines
};
std::ostream& operator<<(std::ostream& file, const polygon& p);
 
/// Rectangle
 
class rectangle : public polygon {
 public:
  /// Central point
  point piv;      
  /// Directions of sides, unit length
  vec dir1;       
  /// Directions of sides, unit length
  vec dir2;       
  // Dimensions
  vfloat dim[2];  
  rectangle() : polygon() {}
  rectangle(const point& fpiv, vec fdir[2], vfloat fdim[2], vfloat prec);
  // Prec is used to check that sides are perpendicular and
  // at initing of the polygon via straight lines.
 protected:
  static absref(absref::*aref_rct[4]);
  virtual absref_transmit get_components() override;
};
std::ostream& operator<<(std::ostream& file, const rectangle& f);
 
/// Special quadrangle (for cathode strip shamber).
/// Two lines are going from a point of origin.
 
class spquadr : public polygon {
 protected:
  point piv;
  vec dir1, dir2;
  /// Width of total plane in units of radians
  vfloat awidth;  
 
 public:
  point Gpiv() const { return piv; }
  vec Gdir1() const { return dir1; }
  vec Gdir2() const { return dir2; }
  vfloat Gawidth() const { return awidth; }
 
 protected:
  static absref(absref::*aref_sp[4]);
  virtual absref_transmit get_components() override;
 
 public:
  /// Position in units of radians.
  vfloat apos(const point& fpt) const { 
    // it is assumed that the point is inside
    return acos(cos2vec(dir1, vec(fpt - piv)));
  }
  vfloat apos(const straight& fsl, vfloat prec) const {
    point pth = cross(fsl, prec);
    if (vecerror != 0) return 0.0;
    return apos(pth);
  }
  /// Perpendicular position. Distance from basis sl[0].
  vfloat perpos(const point& fpt) const { 
    // it is assumed that the point is inside
    vfloat r = sl[0].distance(fpt);
    return r;
  }
  vfloat perpos(const straight& fsl, vfloat prec) const {
    point pth = cross(fsl, prec);
    if (vecerror != 0) return 0.0;
    return perpos(pth);
  }
  point pt_angle_rad(vfloat rad, vfloat angle);
 
  spquadr() : polygon(), piv(), dir1(), dir2(), awidth(0) {}
 
  spquadr(spquadr& sq);
  spquadr(const spquadr& sq);
 
  spquadr(const point& fpiv, const straight& sl1, const straight& sl2,
          const vec& fdir1, const vec& fdir2, vfloat prec);
 
  friend std::ostream& operator<<(std::ostream& file, const spquadr& p);
 
 private:
  spquadr(const point& fpiv, const straight& /*sl1*/, const straight& /*sl2*/,
          const vec& fdir1, const vec& fdir2, polygon& fplgn)
      : polygon(fplgn),
        piv(fpiv),
        dir1(unit_vec(fdir1)),
        dir2(unit_vec(fdir2)) {
    awidth = acos(cos2vec(dir1, dir2));
  }
};
 
std::ostream& operator<<(std::ostream& file, const spquadr& p);
}
 
#endif