source/libmarklin/vehicle.cpp

   1 /* $Id$
   2
   3 This file is part of the MSP Märklin suite
   4 Copyright © 2010  Mikkosoft Productions, Mikko Rasa
   5 Distributed under the GPL
   6 */
   7
   8 #include <cmath>
   9 #include "catalogue.h"
  10 #include "driver.h"
  11 #include "layout.h"
  12 #include "track.h"
  13 #include "tracktype.h"
  14 #include "vehicle.h"
  15 #include "vehicletype.h"
  16
  17 using namespace std;
  18 using namespace Msp;
  19
  20 namespace Marklin {
  21
  22 Vehicle::Vehicle(Layout &l, const VehicleType &t):
  23         layout(l),
  24         type(t),
  25         next(0),
  26         prev(0),
  27         direction(0),
  28         bogie_dirs(type.get_bogies().size()),
  29         front_sensor(0),
  30         back_sensor(0)
  31 {
  32         layout.add_vehicle(*this);
  33 }
  34
  35 Vehicle::~Vehicle()
  36 {
  37         if(next)
  38                 detach_back();
  39         if(prev)
  40                 detach_front();
  41         layout.remove_vehicle(*this);
  42 }
  43
  44 void Vehicle::attach_back(Vehicle &veh)
  45 {
  46         if(next || veh.prev)
  47                 throw InvalidState("Already attached");
  48
  49         next = &veh;
  50         veh.prev = this;
  51
  52         if(track_pos.track)
  53                 propagate_backward();
  54 }
  55
  56 void Vehicle::attach_front(Vehicle &veh)
  57 {
  58         if(prev || veh.next)
  59                 throw InvalidState("Already attached");
  60
  61         prev = &veh;
  62         veh.next = this;
  63
  64         if(prev->get_track())
  65                 prev->propagate_backward();
  66 }
  67
  68 void Vehicle::detach_back()
  69 {
  70         if(!next)
  71                 throw InvalidState("Not attached");
  72
  73         next->prev = 0;
  74         next = 0;
  75 }
  76
  77 void Vehicle::detach_front()
  78 {
  79         if(!prev)
  80                 throw InvalidState("Not attached");
  81
  82         prev->next = 0;
  83         prev = 0;
  84 }
  85
  86 void Vehicle::place(Track *t, unsigned e, float o, PlaceMode m)
  87 {
  88         track_pos = TrackPosition(t, e, o);
  89
  90         if(m==FRONT_AXLE)
  91                 track_pos.advance(-type.get_front_axle_offset());
  92         else if(m==FRONT_BUFFER)
  93                 track_pos.advance(-type.get_length()/2);
  94         else if(m==BACK_AXLE)
  95                 track_pos.advance(-type.get_back_axle_offset());
  96         else if(m==BACK_BUFFER)
  97                 track_pos.advance(type.get_length()/2);
  98
  99         update_position();
 100         propagate_position();
 101 }
 102
 103 void Vehicle::advance(float d)
 104 {
 105         track_pos.advance(d);
 106         update_position();
 107         propagate_position();
 108 }
 109
 110 float Vehicle::get_bogie_direction(unsigned i) const
 111 {
 112         if(i>=bogie_dirs.size())
 113                 throw InvalidParameterValue("Bogie index out of range");
 114         return bogie_dirs[i];
 115 }
 116
 117 void Vehicle::update_position()
 118 {
 119         TrackPoint tp;
 120
 121         const vector<VehicleType::Axle> &axles = type.get_axles();
 122         const vector<VehicleType::Bogie> &bogies = type.get_bogies();
 123         if(axles.size()>=2)
 124         {
 125                 float wheelbase = axles.front().position-axles.back().position;
 126                 tp = get_point(track_pos, wheelbase, -axles.back().position/wheelbase);
 127         }
 128         else if(bogies.size()>=2)
 129         {
 130                 TrackPosition front = track_pos;
 131                 front.advance(bogies.front().position);
 132                 TrackPosition back = track_pos;
 133                 back.advance(bogies.back().position);
 134                 float bogie_spacing = bogies.front().position-bogies.back().position;
 135                 adjust_for_distance(front, back, bogie_spacing);
 136
 137                 const vector<VehicleType::Axle> &front_axles = bogies.front().axles;
 138                 float wheelbase = front_axles.front().position-front_axles.back().position;
 139                 TrackPoint front_point = get_point(front, wheelbase, -front_axles.back().position/wheelbase);
 140
 141                 const vector<VehicleType::Axle> &back_axles = bogies.back().axles;
 142                 wheelbase = back_axles.front().position-back_axles.back().position;
 143                 TrackPoint back_point = get_point(back, wheelbase, -back_axles.back().position/wheelbase);
 144
 145                 tp = get_point(front_point.pos, back_point.pos, -bogies.back().position/bogie_spacing);
 146
 147                 bogie_dirs.front() = front_point.dir-tp.dir;
 148                 bogie_dirs.back() = back_point.dir-tp.dir;
 149         }
 150         else
 151                 tp = track_pos.get_point();
 152
 153         if(!prev)
 154                 check_sensor(type.get_front_axle_offset(), front_sensor);
 155         if(!next)
 156                 check_sensor(type.get_back_axle_offset(), back_sensor);
 157
 158         position = tp.pos;
 159         direction = tp.dir;
 160 }
 161
 162 void Vehicle::update_position_from(const Vehicle &veh)
 163 {
 164         int sign = (&veh==prev ? -1 : 1);
 165
 166         float tdist = (type.get_length()+veh.type.get_length())/2;
 167         float margin = layout.get_catalogue().get_scale();
 168
 169         float dist = distance(veh.position, position);
 170         if(dist<tdist-margin || dist>tdist+margin)
 171         {
 172                 track_pos = veh.track_pos;
 173                 track_pos.advance(sign*tdist);
 174                 update_position();
 175
 176                 dist = distance(veh.position, position);
 177         }
 178
 179         track_pos.advance(sign*(tdist-dist));
 180         update_position();
 181 }
 182
 183 void Vehicle::propagate_position()
 184 {
 185         if(prev)
 186                 propagate_forward();
 187         if(next)
 188                 propagate_backward();
 189 }
 190
 191 void Vehicle::propagate_forward()
 192 {
 193         prev->update_position_from(*this);
 194
 195         if(prev->prev)
 196                 prev->propagate_forward();
 197 }
 198
 199 void Vehicle::propagate_backward()
 200 {
 201         next->update_position_from(*this);
 202
 203         if(next->next)
 204                 next->propagate_backward();
 205 }
 206
 207 void Vehicle::check_sensor(float offset, unsigned &sensor)
 208 {
 209         TrackPosition pos = track_pos;
 210         pos.advance(offset);
 211         unsigned s = pos.track->get_sensor_id();
 212         if(s!=sensor)
 213         {
 214                 /* Sensor ID under axle has changed.  Deduce movement direction by using
 215                 the sensor ID under the midpoint of the vehicle. */
 216                 /* XXX This depends on the simulation running fast enough.  Something
 217                 more robust would be preferable. */
 218                 unsigned old = sensor;
 219                 sensor = s;
 220                 unsigned mid = track_pos.track->get_sensor_id();
 221
 222                 if(s && s!=mid)
 223                         /* There's a sensor and it's different from mid.  We've just entered
 224                         that sensor. */
 225                         layout.get_driver().set_sensor(sensor, true);
 226                 if(old && old!=mid)
 227                         /* A sensor was under the axle and it was different from mid.  We've
 228                         just left that sensor. */
 229                         layout.get_driver().set_sensor(old, false);
 230         }
 231 }
 232
 233 void Vehicle::adjust_for_distance(TrackPosition &front, TrackPosition &back, float tdist, float ratio) const
 234 {
 235         float margin = 0.01*layout.get_catalogue().get_scale();
 236         int adjust_dir = 0;
 237         while(1)
 238         {
 239                 Point front_point = front.get_point().pos;
 240                 Point back_point = back.get_point().pos;
 241
 242                 float dx = front_point.x-back_point.x;
 243                 float dy = front_point.y-back_point.y;
 244                 float dz = front_point.z-back_point.z;
 245                 float dist = sqrt(dx*dx+dy*dy+dz*dz);
 246
 247                 float diff = tdist-dist;
 248                 if(diff<-margin && adjust_dir<=0)
 249                 {
 250                         diff -= margin;
 251                         adjust_dir = -1;
 252                 }
 253                 else if(diff>margin && adjust_dir>=0)
 254                 {
 255                         diff += margin;
 256                         adjust_dir = 1;
 257                 }
 258                 else
 259                         return;
 260
 261                 front.advance(diff*(1-ratio));
 262                 back.advance(-diff*ratio);
 263         }
 264 }
 265
 266 TrackPoint Vehicle::get_point(const Point &front, const Point &back, float ratio) const
 267 {
 268         float dx = front.x-back.x;
 269         float dy = front.y-back.y;
 270         float dz = front.z-back.z;
 271
 272         TrackPoint tp;
 273         tp.pos = Point(back.x+dx*ratio, back.y+dy*ratio, back.z+dz*ratio);
 274         tp.dir = atan2(dy, dx);
 275
 276         return tp;
 277 }
 278
 279 TrackPoint Vehicle::get_point(const TrackPosition &pos, float tdist, float ratio) const
 280 {
 281         TrackPosition front = pos;
 282         front.advance(tdist*(1-ratio));
 283
 284         TrackPosition back = pos;
 285         back.advance(-tdist*ratio);
 286
 287         adjust_for_distance(front, back, tdist, ratio);
 288         return get_point(front.get_point().pos, back.get_point().pos, ratio);
 289 }
 290
 291
 292 Vehicle::TrackPosition::TrackPosition():
 293         track(0),
 294         ep(0),
 295         offs(0)
 296 { }
 297
 298 Vehicle::TrackPosition::TrackPosition(Track *t, unsigned e, float o):
 299         track(t),
 300         ep(e),
 301         offs(o)
 302 { }
 303
 304 void Vehicle::TrackPosition::advance(float d)
 305 {
 306         if(!track)
 307                 return;
 308
 309         unsigned path = track->get_active_path();
 310
 311         offs += d;
 312         float path_len = track->get_type().get_path_length(path);
 313         while(track && offs>=path_len)
 314         {
 315                 unsigned out = track->traverse(ep, path);
 316                 Track *next = track->get_link(out);
 317
 318                 if(next)
 319                 {
 320                         ep = next->get_endpoint_by_link(*track);
 321                         track = next;
 322
 323                         offs -= path_len;
 324                         path = track->get_active_path();
 325                         path_len = track->get_type().get_path_length(path);
 326                 }
 327                 else
 328                         track = 0;
 329         }
 330
 331         while(track && offs<0)
 332         {
 333                 Track *prev = track->get_link(ep);
 334                 if(prev)
 335                 {
 336                         unsigned in = prev->get_endpoint_by_link(*track);
 337                         track = prev;
 338
 339                         path = track->get_active_path();
 340                         ep = track->traverse(in, path);
 341
 342                         path_len = track->get_type().get_path_length(path);
 343                         offs += path_len;
 344                 }
 345                 else
 346                         track = 0;
 347         }
 348
 349         if(!track)
 350         {
 351                 ep = 0;
 352                 offs = 0;
 353         }
 354 }
 355
 356 TrackPoint Vehicle::TrackPosition::get_point() const
 357 {
 358         if(track)
 359                 return track->get_point(ep, offs);
 360         else
 361                 return TrackPoint();
 362 }
 363
 364 } // namespace Marklin