source/libr2c2/tracktype.cpp

   1 #include <cmath>
   2 #include <msp/datafile/collection.h>
   3 #include <msp/geometry/union.h>
   4 #include "trackappearance.h"
   5 #include "tracktype.h"
   6
   7 using namespace std;
   8 using namespace Msp;
   9
  10 namespace R2C2 {
  11
  12 TrackType::TrackType():
  13         appearance(0),
  14         state_bits(0),
  15         autofit_preference(1)
  16 { }
  17
  18 const TrackAppearance &TrackType::get_appearance() const
  19 {
  20         if(!appearance)
  21                 throw logic_error("no appearance");
  22         return *appearance;
  23 }
  24
  25 float TrackType::get_gauge() const
  26 {
  27         return get_appearance().get_gauge();
  28 }
  29
  30 float TrackType::get_total_length() const
  31 {
  32         return get_path_length(-1);
  33 }
  34
  35 float TrackType::get_path_length(int p) const
  36 {
  37         float len = 0;
  38         for(vector<TrackPart>::const_iterator i=parts.begin(); i!=parts.end(); ++i)
  39                 if(p<0 || i->get_path()==static_cast<unsigned>(p))
  40                         len += i->get_length();
  41         return len;
  42 }
  43
  44 unsigned TrackType::get_paths() const
  45 {
  46         unsigned mask = 0;
  47         for(vector<TrackPart>::const_iterator i=parts.begin(); i!=parts.end(); ++i)
  48                 mask |= 1<<i->get_path();
  49         return mask;
  50 }
  51
  52 unsigned TrackType::get_n_paths() const
  53 {
  54         unsigned n = 0;
  55         for(unsigned mask = get_paths(); mask; ++n)
  56                 mask &= mask-1;
  57         return n;
  58 }
  59
  60 unsigned TrackType::coerce_path(unsigned entry, unsigned path) const
  61 {
  62         const Endpoint &ep = get_endpoint(entry);
  63         if(ep.has_path(path))
  64                 return path;
  65
  66         unsigned paths = get_paths();
  67         if(paths>>(1<<state_bits))
  68         {
  69                 /* There are more paths than can be expressed with state_bits, so
  70                 multiple paths are set at once.  See if one of the alternatives fits. */
  71                 unsigned step = 1<<state_bits;
  72                 for(unsigned p=path+step; paths>>p; p+=step)
  73                         if(ep.has_path(p))
  74                                 return p;
  75         }
  76
  77         // Find an endpoint that's connected to the entry and has the requested path
  78         for(vector<Endpoint>::const_iterator i=endpoints.begin(); i!=endpoints.end(); ++i)
  79                 if(i->has_path(path) && i->has_common_paths(ep))
  80                 {
  81                         unsigned p = 1;
  82                         for(unsigned m=i->paths&ep.paths; m>>p; ++p) ;
  83                         return p-1;
  84                 }
  85
  86         // TODO crossings fall here
  87         throw logic_error("TrackType::coerce_path");
  88 }
  89
  90 bool TrackType::is_turnout() const
  91 {
  92         return endpoints.size()>2;
  93 }
  94
  95 bool TrackType::is_dead_end() const
  96 {
  97         return endpoints.size()<2;
  98 }
  99
 100 const TrackType::Endpoint &TrackType::get_endpoint(unsigned i) const
 101 {
 102         if(i>=endpoints.size())
 103                 throw out_of_range("TrackType::get_endpoint");
 104
 105         return endpoints[i];
 106 }
 107
 108 OrientedPoint TrackType::get_point(unsigned epi, unsigned path, float d) const
 109 {
 110         if(epi>=endpoints.size())
 111                 throw out_of_range("TrackType::get_point");
 112
 113         const TrackPart *part = 0;
 114         unsigned part_ep = 0;
 115         for(vector<TrackPart>::const_iterator i=parts.begin(); i!=parts.end(); ++i)
 116         {
 117                 if(endpoints[epi].has_path(path) && i->get_path()!=path)
 118                         continue;
 119
 120                 unsigned n_part_eps = (i->is_dead_end() ? 1 : 2);
 121                 for(unsigned j=0; j<n_part_eps; ++j)
 122                 {
 123                         OrientedPoint p = i->get_point(j ? i->get_length() : 0);
 124                         Vector span = p.position-endpoints[epi].pos;
 125                         if(dot(span, span)<1e-6)
 126                         {
 127                                 part = &*i;
 128                                 part_ep = j;
 129                         }
 130                 }
 131         }
 132
 133         if(!part)
 134                 throw logic_error("internal error (endpoint does not match any part)");
 135
 136         while(1)
 137         {
 138                 float plen = part->get_length();
 139                 if(d<=plen)
 140                 {
 141                         if(part_ep==1)
 142                                 d = plen-d;
 143                         OrientedPoint p = part->get_point(d);
 144                         if(part_ep==1)
 145                                 p.rotation += Angle::half_turn();
 146                         return p;
 147                 }
 148                 else
 149                 {
 150                         d -= plen;
 151                         TrackPart *next = part->get_link(1-part_ep);
 152                         if(!next)
 153                                 throw invalid_argument("TrackType::get_point");
 154                         part_ep = (next->get_link(0)==part ? 0 : 1);
 155                         part = next;
 156                 }
 157         }
 158 }
 159
 160 OrientedPoint TrackType::get_nearest_point(const Vector &p) const
 161 {
 162         OrientedPoint result;
 163         float dist = -1;
 164
 165         for(vector<TrackPart>::const_iterator i=parts.begin(); i!=parts.end(); ++i)
 166         {
 167                 OrientedPoint n = i->get_nearest_point(p);
 168                 float d = distance(n.position, p);
 169                 if(d<dist || dist<0)
 170                 {
 171                         result = n;
 172                         dist = d;
 173                 }
 174         }
 175
 176         return result;
 177 }
 178
 179 void TrackType::collect_endpoints()
 180 {
 181         endpoints.clear();
 182
 183         for(vector<TrackPart>::iterator i=parts.begin(); i!=parts.end(); ++i)
 184         {
 185                 for(vector<TrackPart>::iterator j=i; ++j!=parts.end();)
 186                         i->check_link(*j);
 187
 188                 unsigned n_part_eps = (i->is_dead_end() ? 1 : 2);
 189                 for(unsigned j=0; j<n_part_eps; ++j)
 190                         if(!i->get_link(j))
 191                         {
 192                                 OrientedPoint p = i->get_point(j ? i->get_length() : 0);
 193                                 if(j==0)
 194                                         p.rotation += Angle::half_turn();
 195
 196                                 bool found = false;
 197                                 for(vector<Endpoint>::iterator k=endpoints.begin(); k!=endpoints.end(); ++k)
 198                                 {
 199                                         Vector d = k->pos-p.position;
 200
 201                                         Angle da = wrap_balanced(k->dir-p.rotation);
 202
 203                                         if(dot(d, d)<1e-6 && abs(da).radians()<0.01)
 204                                         {
 205                                                 k->paths |= 1<<i->get_path();
 206                                                 found = true;
 207                                                 break;
 208                                         }
 209                                 }
 210
 211                                 if(!found)
 212                                         endpoints.push_back(Endpoint(p.position.x, p.position.y, p.rotation, 1<<i->get_path()));
 213                         }
 214         }
 215 }
 216
 217 TrackType::Endpoint::Endpoint(float x, float y, const Angle &d, unsigned p):
 218         pos(x, y, 0),
 219         dir(d),
 220         paths(p)
 221 { }
 222
 223
 224 TrackType::Loader::Loader(TrackType &t, Collection &c):
 225         DataFile::DerivedObjectLoader<TrackType, ObjectType::Loader>(t),
 226         coll(c),
 227         state_bits_set(false)
 228 {
 229         add("appearance",  &TrackType::appearance);
 230         add("autofit_preference", &TrackType::autofit_preference);
 231         add("object",      &TrackType::object);
 232         add("state_bits",  &Loader::state_bits);
 233         add("part",        &Loader::part);
 234 }
 235
 236 void TrackType::Loader::finish()
 237 {
 238         obj.collect_endpoints();
 239         vector<const Shape *> shapes;
 240         for(vector<TrackPart>::iterator i=obj.parts.begin(); i!=obj.parts.end(); ++i)
 241         {
 242                 i->create_shape();
 243                 shapes.push_back(&i->get_shape());
 244         }
 245         obj.shape = Geometry::Union<float, 3>::from_iterator_range(shapes.begin(), shapes.end()).clone();
 246 }
 247
 248 void TrackType::Loader::part()
 249 {
 250         TrackPart p;
 251         load_sub(p);
 252         obj.parts.push_back(p);
 253         if(!state_bits_set && p.get_path())
 254                 while(p.get_path()>=(1U<<obj.state_bits))
 255                         ++obj.state_bits;
 256 }
 257
 258 void TrackType::Loader::state_bits(unsigned b)
 259 {
 260         obj.state_bits = b;
 261         state_bits_set = true;
 262 }
 263
 264 } // namespace R2C2