perception/obstacle.cc

   1 /*
   2 This file is part of I am car.
   3
   4 I am car is free software: you can redistribute it and/or modify
   5 it under the terms of the GNU General Public License as published by
   6 the Free Software Foundation, either version 3 of the License, or
   7 (at your option) any later version.
   8
   9 I am car is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with I am car. If not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18 #include <cmath>
  19 #include "obstacle.h"
  20
  21 float CircleObstacle::r()
  22 {
  23         return this->h();
  24 }
  25
  26 bool CircleObstacle::collide(RRTNode *n)
  27 {
  28         float xx = n->x() - this->x();
  29         xx *= xx;
  30         float yy = n->y() - this->y();
  31         yy *= yy;
  32         float rr = this->r() * this->r();
  33         if (xx + yy <= rr) {
  34                 return true;
  35         }
  36         return false;
  37 }
  38
  39 bool CircleObstacle::collide(RRTEdge *e)
  40 {
  41         // see http://doswa.com/2009/07/13/circle-segment-intersectioncollision.html
  42         // Find the closest point on seq.
  43         float seg_v[] = {
  44                 e->goal()->x() - e->init()->x(),
  45                 e->goal()->y() - e->init()->y()
  46         };
  47         float pt_v[] = {
  48                 this->x() - e->init()->x(),
  49                 this->y() - e->init()->y()
  50         };
  51         float seg_vl = sqrt(pow(seg_v[0], 2) + pow(seg_v[1], 2));
  52         // seg_vl must be > 0 otherwise it is invalid segment length.
  53         if (seg_vl <= 0)
  54                 return false;
  55         float seg_v_unit[] = {seg_v[0] / seg_vl, seg_v[1] / seg_vl};
  56         float proj = pt_v[0]*seg_v_unit[0] + pt_v[1]*seg_v_unit[1];
  57         float closest[] = {0, 0};
  58         if (proj <= 0) {
  59                 closest[0] = e->init()->x();
  60                 closest[1] = e->init()->y();
  61         } else if (proj >= seg_vl) {
  62                 closest[0] = e->goal()->x();
  63                 closest[1] = e->goal()->y();
  64         } else {
  65                 float proj_v[] = {seg_v_unit[0] * proj, seg_v_unit[1] * proj};
  66                 closest[0] = proj_v[0] + e->init()->x();
  67                 closest[1] = proj_v[1] + e->init()->y();
  68         }
  69         // Find the segment circle.
  70         float dist_v[] = {this->x() - closest[0], this->y() - closest[1]};
  71         float dist = sqrt(pow(dist_v[0], 2) + pow(dist_v[1], 2));
  72         if (dist <= this->r())
  73                 return true;
  74         return false;
  75         // Offset computation.
  76         // float offset[] = {
  77         //        dist_v[0] / dist * (BCAR_TURNING_RADIUS - dist),
  78         //        dist_v[1] / dist * (BCAR_TURNING_RADIUS - dist)
  79         // };
  80 }
  81
  82 bool CircleObstacle::collide(std::vector<RRTEdge *> &edges)
  83 {
  84         for (auto e: edges)
  85                 if (this->collide(e))
  86                         return true;
  87         return false;
  88 }
  89
  90 float CircleObstacle::dist_to(RRTNode *n)
  91 {
  92         float xx = n->x() - this->x();
  93         xx *= xx;
  94         float yy = n->y() - this->y();
  95         yy *= yy;
  96         return (float) (sqrt(xx + yy) - this->r());
  97 }
  98
  99 void PolygonObstacle::add_bnode(RRTNode *n)
 100 {
 101         this->bnodes_.push_back(n);
 102 }
 103
 104 bool PolygonObstacle::collide(RRTNode *n)
 105 {
 106         // From substack/point-in-polygon, see
 107         // https://github.com/substack/point-in-polygon/blob/master/index.js
 108         bool inside = false;
 109         unsigned int i;
 110         int j;
 111         for (i = 0, j = this->bnodes_.size() - 1;
 112                         i < this->bnodes_.size();
 113                         j = i++) {
 114                 float xi = this->bnodes_[i]->x();
 115                 float yi = this->bnodes_[i]->y();
 116                 float xj = this->bnodes_[j]->x();
 117                 float yj = this->bnodes_[j]->y();
 118                 bool intersect = ((yi > n->y()) != (yj > n->y())) &&
 119                         (n->x() < (xj - xi) * (n->y() - yi) / (yj - yi) + xi);
 120                 if (intersect)
 121                         inside = !inside;
 122         }
 123         return inside;
 124 }
 125
 126 bool PolygonObstacle::collide(RRTEdge *e)
 127 {
 128         for (auto &f: this->frame()) {
 129                 if (SegmentObstacle(f->init(), f->goal()).collide(e))
 130                         return true;
 131         }
 132         return false;
 133 }
 134
 135 bool PolygonObstacle::collide(std::vector<RRTEdge *> &edges)
 136 {
 137         for (auto &e: edges) {
 138                 if (this->collide(e))
 139                         return true;
 140         }
 141         return false;
 142 }
 143
 144 bool PolygonObstacle::collide(std::vector<RRTEdge *> edges)
 145 {
 146         for (auto &e: edges) {
 147                 if (this->collide(e))
 148                         return true;
 149         }
 150         return false;
 151 }
 152
 153 float PolygonObstacle::dist_to(RRTNode *n)
 154 {
 155         return 0;
 156 }
 157
 158 std::vector<RRTEdge *> PolygonObstacle::frame()
 159 {
 160         std::vector<RRTEdge *> frame;
 161         unsigned int i;
 162         int j;
 163         for (i = 1, j = 0; i < this->bnodes_.size(); j = i++) {
 164                 frame.push_back(new RRTEdge(
 165                         new RRTNode(
 166                                 this->bnodes_[j]->x(),
 167                                 this->bnodes_[j]->y(),
 168                                 this->bnodes_[j]->h()
 169                         ),
 170                         new RRTNode(
 171                                 this->bnodes_[i]->x(),
 172                                 this->bnodes_[i]->y(),
 173                                 this->bnodes_[i]->h()
 174                         )
 175                 ));
 176         }
 177         return frame;
 178 }
 179
 180 std::vector<RRTNode *> &PolygonObstacle::bnodes()
 181 {
 182         return this->bnodes_;
 183 }
 184
 185 bool SegmentObstacle::collide(RRTNode *n)
 186 {
 187         return false;
 188 }
 189
 190 bool SegmentObstacle::collide(RRTEdge *e)
 191 {
 192         if (this->intersect(e, true))
 193                 return true;
 194         return false;
 195 }
 196
 197 bool SegmentObstacle::collide(std::vector<RRTEdge *> &edges)
 198 {
 199         for (auto &e: edges) {
 200                 if (this->collide(e)) {
 201                         return true;
 202                 }
 203         }
 204         return false;
 205 }
 206
 207 float SegmentObstacle::dist_to(RRTNode *n)
 208 {
 209         // see https://en.wikipedia.org/wiki/Distance_from_a_point_to_a_line
 210         float x1 = this->init()->x();
 211         float y1 = this->init()->y();
 212         float x2 = this->goal()->x();
 213         float y2 = this->goal()->y();
 214         float x0 = n->x();
 215         float y0 = n->y();
 216         float nume = (y2 - y1) * x0 - (x2 - x1) * y0 + x2 * y1 - y2 * x1;
 217         nume = std::abs(nume);
 218         float deno = sqrt(pow(y2 - y1, 2) + pow(x2 - x1, 2));
 219         return nume / deno;
 220 }