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         position.z += layout.get_catalogue().get_rail_elevation();
 160         direction = tp.dir;
 161 }
 162
 163 void Vehicle::update_position_from(const Vehicle &veh)
 164 {
 165         int sign = (&veh==prev ? -1 : 1);
 166
 167         float tdist = (type.get_length()+veh.type.get_length())/2;
 168         float margin = layout.get_catalogue().get_scale();
 169
 170         float dist = distance(veh.position, position);
 171         if(dist<tdist-margin || dist>tdist+margin)
 172         {
 173                 track_pos = veh.track_pos;
 174                 track_pos.advance(sign*tdist);
 175                 update_position();
 176
 177                 dist = distance(veh.position, position);
 178         }
 179
 180         track_pos.advance(sign*(tdist-dist));
 181         update_position();
 182 }
 183
 184 void Vehicle::propagate_position()
 185 {
 186         if(prev)
 187                 propagate_forward();
 188         if(next)
 189                 propagate_backward();
 190 }
 191
 192 void Vehicle::propagate_forward()
 193 {
 194         prev->update_position_from(*this);
 195
 196         if(prev->prev)
 197                 prev->propagate_forward();
 198 }
 199
 200 void Vehicle::propagate_backward()
 201 {
 202         next->update_position_from(*this);
 203
 204         if(next->next)
 205                 next->propagate_backward();
 206 }
 207
 208 void Vehicle::check_sensor(float offset, unsigned &sensor)
 209 {
 210         TrackPosition pos = track_pos;
 211         pos.advance(offset);
 212         unsigned s = pos.track->get_sensor_id();
 213         if(s!=sensor)
 214         {
 215                 /* Sensor ID under axle has changed.  Deduce movement direction by using
 216                 the sensor ID under the midpoint of the vehicle. */
 217                 /* XXX This depends on the simulation running fast enough.  Something
 218                 more robust would be preferable. */
 219                 unsigned old = sensor;
 220                 sensor = s;
 221                 unsigned mid = track_pos.track->get_sensor_id();
 222
 223                 if(s && s!=mid)
 224                         /* There's a sensor and it's different from mid.  We've just entered
 225                         that sensor. */
 226                         layout.get_driver().set_sensor(sensor, true);
 227                 if(old && old!=mid)
 228                         /* A sensor was under the axle and it was different from mid.  We've
 229                         just left that sensor. */
 230                         layout.get_driver().set_sensor(old, false);
 231         }
 232 }
 233
 234 void Vehicle::adjust_for_distance(TrackPosition &front, TrackPosition &back, float tdist, float ratio) const
 235 {
 236         float margin = 0.01*layout.get_catalogue().get_scale();
 237         int adjust_dir = 0;
 238         while(1)
 239         {
 240                 Point front_point = front.get_point().pos;
 241                 Point back_point = back.get_point().pos;
 242
 243                 float dx = front_point.x-back_point.x;
 244                 float dy = front_point.y-back_point.y;
 245                 float dz = front_point.z-back_point.z;
 246                 float dist = sqrt(dx*dx+dy*dy+dz*dz);
 247
 248                 float diff = tdist-dist;
 249                 if(diff<-margin && adjust_dir<=0)
 250                 {
 251                         diff -= margin;
 252                         adjust_dir = -1;
 253                 }
 254                 else if(diff>margin && adjust_dir>=0)
 255                 {
 256                         diff += margin;
 257                         adjust_dir = 1;
 258                 }
 259                 else
 260                         return;
 261
 262                 front.advance(diff*(1-ratio));
 263                 back.advance(-diff*ratio);
 264         }
 265 }
 266
 267 TrackPoint Vehicle::get_point(const Point &front, const Point &back, float ratio) const
 268 {
 269         float dx = front.x-back.x;
 270         float dy = front.y-back.y;
 271         float dz = front.z-back.z;
 272
 273         TrackPoint tp;
 274         tp.pos = Point(back.x+dx*ratio, back.y+dy*ratio, back.z+dz*ratio);
 275         tp.dir = atan2(dy, dx);
 276
 277         return tp;
 278 }
 279
 280 TrackPoint Vehicle::get_point(const TrackPosition &pos, float tdist, float ratio) const
 281 {
 282         TrackPosition front = pos;
 283         front.advance(tdist*(1-ratio));
 284
 285         TrackPosition back = pos;
 286         back.advance(-tdist*ratio);
 287
 288         adjust_for_distance(front, back, tdist, ratio);
 289         return get_point(front.get_point().pos, back.get_point().pos, ratio);
 290 }
 291
 292
 293 Vehicle::TrackPosition::TrackPosition():
 294         track(0),
 295         ep(0),
 296         offs(0)
 297 { }
 298
 299 Vehicle::TrackPosition::TrackPosition(Track *t, unsigned e, float o):
 300         track(t),
 301         ep(e),
 302         offs(o)
 303 { }
 304
 305 void Vehicle::TrackPosition::advance(float d)
 306 {
 307         if(!track)
 308                 return;
 309
 310         unsigned path = track->get_active_path();
 311
 312         offs += d;
 313         float path_len = track->get_type().get_path_length(path);
 314         while(track && offs>=path_len)
 315         {
 316                 unsigned out = track->traverse(ep, path);
 317                 Track *next = track->get_link(out);
 318
 319                 if(next)
 320                 {
 321                         ep = next->get_endpoint_by_link(*track);
 322                         track = next;
 323
 324                         offs -= path_len;
 325                         path = track->get_active_path();
 326                         path_len = track->get_type().get_path_length(path);
 327                 }
 328                 else
 329                         track = 0;
 330         }
 331
 332         while(track && offs<0)
 333         {
 334                 Track *prev = track->get_link(ep);
 335                 if(prev)
 336                 {
 337                         unsigned in = prev->get_endpoint_by_link(*track);
 338                         track = prev;
 339
 340                         path = track->get_active_path();
 341                         ep = track->traverse(in, path);
 342
 343                         path_len = track->get_type().get_path_length(path);
 344                         offs += path_len;
 345                 }
 346                 else
 347                         track = 0;
 348         }
 349
 350         if(!track)
 351         {
 352                 ep = 0;
 353                 offs = 0;
 354         }
 355 }
 356
 357 TrackPoint Vehicle::TrackPosition::get_point() const
 358 {
 359         if(track)
 360                 return track->get_point(ep, offs);
 361         else
 362                 return TrackPoint();
 363 }
 364
 365 } // namespace Marklin