src/libengrid/polyline.h

   1 // ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
   2 // +                                                                      +
   3 // + This file is part of enGrid.                                         +
   4 // +                                                                      +
   5 // + Copyright 2008-2014 enGits GmbH                                      +
   6 // +                                                                      +
   7 // + enGrid is free software: you can redistribute it and/or modify       +
   8 // + it under the terms of the GNU General Public License as published by +
   9 // + the Free Software Foundation, either version 3 of the License, or    +
  10 // + (at your option) any later version.                                  +
  11 // +                                                                      +
  12 // + enGrid is distributed in the hope that it will be useful,            +
  13 // + but WITHOUT ANY WARRANTY; without even the implied warranty of       +
  14 // + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        +
  15 // + GNU General Public License for more details.                         +
  16 // +                                                                      +
  17 // + You should have received a copy of the GNU General Public License    +
  18 // + along with enGrid. If not, see <http://www.gnu.org/licenses/>.       +
  19 // +                                                                      +
  20 // ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  21 //
  22 #ifndef POLYLINE_H
  23 #define POLYLINE_H
  24
  25 class PolyLine;
  26
  27 #include "curve.h"
  28
  29 #include <QVector>
  30 #include <QFile>
  31 #include <QTextStream>
  32
  33 class PolyLine : public Curve
  34 {
  35
  36 protected: // attributes
  37
  38   QVector<vec3_t> m_Points;
  39   double          m_Length;
  40
  41
  42 protected: // methods
  43
  44   template <typename Q_CONTAINER1, typename Q_CONTAINER2>
  45   int findClosest(vec3_t x, const Q_CONTAINER1& points, const Q_CONTAINER2& exclude);
  46
  47   void getStencil(double l, int &i1, int &i2, double &w1, double &w2);
  48
  49 public:
  50
  51   template <typename Q_CONTAINER>
  52   void fromPointsFile(QString points_file, const Q_CONTAINER& start_points);
  53
  54   virtual vec3_t position(double l);
  55   virtual vec3_t normal(double l);
  56   virtual vec3_t intersection(vec3_t x, vec3_t n);
  57
  58 };
  59
  60 template <typename Q_CONTAINER>
  61 void PolyLine::fromPointsFile(QString points_file, const Q_CONTAINER& start_points)
  62 {
  63   // read raw point data from file
  64   QFile file(points_file);
  65   file.open(QIODevice::ReadOnly);
  66   QTextStream f(&file);
  67   QList<vec3_t> raw_points;
  68   while (!f.atEnd()) {
  69     QString line = f.readLine();
  70     QStringList parts = line.split(",");
  71     if (parts.size() >= 3) {
  72       vec3_t x;
  73       x[0] = parts[0].trimmed().toDouble();
  74       x[1] = parts[1].trimmed().toDouble();
  75       x[2] = parts[2].trimmed().toDouble();
  76       raw_points << x;
  77     }
  78   }
  79
  80   // find start point of poly-line
  81   QList<int> exclude;
  82   int i_start = 0;
  83   double min_dist = EG_LARGE_REAL;
  84   foreach (vec3_t x, start_points) {
  85     int i_best = findClosest(x, raw_points, exclude);
  86     double dist = (x - raw_points[i_best]).abs();
  87     if (dist < min_dist) {
  88       min_dist = dist;
  89       i_start = i_best;
  90     }
  91   }
  92
  93   // sort points in such a way that they form a curve ...
  94   m_Points.resize(raw_points.size());
  95   m_Points[0] = raw_points[i_start];
  96   exclude << i_start;
  97   for (int i = 1; i < raw_points.size(); ++i) {
  98     int i_next = findClosest(m_Points[i-1], raw_points, exclude);
  99     m_Points[i] = raw_points[i_next];
 100     exclude << i_next;
 101   }
 102
 103   // compute the total length of the curve
 104   m_Length = 0;
 105   for (int i = 1; i < m_Points.size(); ++i) {
 106     m_Length += (m_Points[i] - m_Points[i-1]).abs();
 107   }
 108 }
 109
 110 template <typename Q_CONTAINER1, typename Q_CONTAINER2>
 111 int PolyLine::findClosest(vec3_t x, const Q_CONTAINER1& points, const Q_CONTAINER2& exclude)
 112 {
 113   int i_best = -1;
 114   double min_dist = EG_LARGE_REAL;
 115   for (int i = 0; i < points.size(); ++i) {
 116     if (!exclude.contains(i)) {
 117       double dist = (points[i] - x).abs();
 118       if (dist < min_dist) {
 119         min_dist = dist;
 120         i_best = i;
 121       }
 122     }
 123   }
 124   return i_best;
 125 }
 126
 127 #endif // POLYLINE_H