source/libr2c2/tracktype.cpp

   1 #include <cmath>
   2 #include <msp/geometry/union.h>
   3 #include "trackappearance.h"
   4 #include "tracktype.h"
   5
   6 using namespace std;
   7 using namespace Msp;
   8
   9 namespace R2C2 {
  10
  11 TrackType::TrackType(const ArticleNumber &an, const TrackAppearance &ta):
  12         ObjectType(an),
  13         appearance(ta),
  14         state_bits(0),
  15         autofit_preference(1)
  16 { }
  17
  18 float TrackType::get_gauge() const
  19 {
  20         return appearance.get_gauge();
  21 }
  22
  23 float TrackType::get_total_length() const
  24 {
  25         return get_path_length(-1);
  26 }
  27
  28 float TrackType::get_path_length(int p) const
  29 {
  30         float len = 0;
  31         for(vector<TrackPart>::const_iterator i=parts.begin(); i!=parts.end(); ++i)
  32                 if(p<0 || i->get_path()==static_cast<unsigned>(p))
  33                         len += i->get_length();
  34         return len;
  35 }
  36
  37 unsigned TrackType::get_paths() const
  38 {
  39         unsigned mask = 0;
  40         for(vector<TrackPart>::const_iterator i=parts.begin(); i!=parts.end(); ++i)
  41                 mask |= 1<<i->get_path();
  42         return mask;
  43 }
  44
  45 unsigned TrackType::get_n_paths() const
  46 {
  47         unsigned n = 0;
  48         for(unsigned mask = get_paths(); mask; ++n)
  49                 mask &= mask-1;
  50         return n;
  51 }
  52
  53 unsigned TrackType::coerce_path(unsigned entry, unsigned path) const
  54 {
  55         const Endpoint &ep = get_endpoint(entry);
  56         if(ep.has_path(path))
  57                 return path;
  58
  59         unsigned paths = get_paths();
  60         if(paths>>(1<<state_bits))
  61         {
  62                 /* There are more paths than can be expressed with state_bits, so
  63                 multiple paths are set at once.  See if one of the alternatives fits. */
  64                 unsigned step = 1<<state_bits;
  65                 for(unsigned p=path+step; paths>>p; p+=step)
  66                         if(ep.has_path(p))
  67                                 return p;
  68         }
  69
  70         // Find an endpoint that's connected to the entry and has the requested path
  71         for(vector<Endpoint>::const_iterator i=endpoints.begin(); i!=endpoints.end(); ++i)
  72                 if(i->has_path(path) && i->has_common_paths(ep))
  73                 {
  74                         unsigned p = 1;
  75                         for(unsigned m=i->paths&ep.paths; m>>p; ++p) ;
  76                         return p-1;
  77                 }
  78
  79         // TODO crossings fall here
  80         throw logic_error("TrackType::coerce_path");
  81 }
  82
  83 bool TrackType::is_turnout() const
  84 {
  85         return endpoints.size()>2;
  86 }
  87
  88 bool TrackType::is_dead_end() const
  89 {
  90         return endpoints.size()<2;
  91 }
  92
  93 const TrackType::Endpoint &TrackType::get_endpoint(unsigned i) const
  94 {
  95         if(i>=endpoints.size())
  96                 throw out_of_range("TrackType::get_endpoint");
  97
  98         return endpoints[i];
  99 }
 100
 101 OrientedPoint TrackType::get_point(unsigned epi, unsigned path, float d) const
 102 {
 103         if(epi>=endpoints.size())
 104                 throw out_of_range("TrackType::get_point");
 105
 106         const TrackPart *part = 0;
 107         unsigned part_ep = 0;
 108         for(vector<TrackPart>::const_iterator i=parts.begin(); i!=parts.end(); ++i)
 109         {
 110                 if(endpoints[epi].has_path(path) && i->get_path()!=path)
 111                         continue;
 112
 113                 unsigned n_part_eps = (i->is_dead_end() ? 1 : 2);
 114                 for(unsigned j=0; j<n_part_eps; ++j)
 115                 {
 116                         OrientedPoint p = i->get_point(j ? i->get_length() : 0);
 117                         Vector span = p.position-endpoints[epi].pos;
 118                         if(dot(span, span)<1e-6)
 119                         {
 120                                 part = &*i;
 121                                 part_ep = j;
 122                         }
 123                 }
 124         }
 125
 126         if(!part)
 127                 throw logic_error("internal error (endpoint does not match any part)");
 128
 129         while(1)
 130         {
 131                 float plen = part->get_length();
 132                 if(d<=plen)
 133                 {
 134                         if(part_ep==1)
 135                                 d = plen-d;
 136                         OrientedPoint p = part->get_point(d);
 137                         if(part_ep==1)
 138                                 p.rotation += Angle::half_turn();
 139                         return p;
 140                 }
 141                 else
 142                 {
 143                         d -= plen;
 144                         TrackPart *next = part->get_link(1-part_ep);
 145                         if(!next)
 146                                 throw invalid_argument("TrackType::get_point");
 147                         part_ep = (next->get_link(0)==part ? 0 : 1);
 148                         part = next;
 149                 }
 150         }
 151 }
 152
 153 OrientedPoint TrackType::get_nearest_point(const Vector &p) const
 154 {
 155         OrientedPoint result;
 156         float dist = -1;
 157
 158         for(vector<TrackPart>::const_iterator i=parts.begin(); i!=parts.end(); ++i)
 159         {
 160                 OrientedPoint n = i->get_nearest_point(p);
 161                 float d = distance(n.position, p);
 162                 if(d<dist || dist<0)
 163                 {
 164                         result = n;
 165                         dist = d;
 166                 }
 167         }
 168
 169         return result;
 170 }
 171
 172 void TrackType::collect_endpoints()
 173 {
 174         endpoints.clear();
 175
 176         for(vector<TrackPart>::iterator i=parts.begin(); i!=parts.end(); ++i)
 177         {
 178                 for(vector<TrackPart>::iterator j=i; ++j!=parts.end();)
 179                         i->check_link(*j);
 180
 181                 unsigned n_part_eps = (i->is_dead_end() ? 1 : 2);
 182                 for(unsigned j=0; j<n_part_eps; ++j)
 183                         if(!i->get_link(j))
 184                         {
 185                                 OrientedPoint p = i->get_point(j ? i->get_length() : 0);
 186                                 if(j==0)
 187                                         p.rotation += Angle::half_turn();
 188
 189                                 bool found = false;
 190                                 for(vector<Endpoint>::iterator k=endpoints.begin(); k!=endpoints.end(); ++k)
 191                                 {
 192                                         Vector d = k->pos-p.position;
 193
 194                                         Angle da = wrap_balanced(k->dir-p.rotation);
 195
 196                                         if(dot(d, d)<1e-6 && abs(da).radians()<0.01)
 197                                         {
 198                                                 k->paths |= 1<<i->get_path();
 199                                                 found = true;
 200                                                 break;
 201                                         }
 202                                 }
 203
 204                                 if(!found)
 205                                         endpoints.push_back(Endpoint(p.position.x, p.position.y, p.rotation, 1<<i->get_path()));
 206                         }
 207         }
 208 }
 209
 210 TrackType::Endpoint::Endpoint(float x, float y, const Angle &d, unsigned p):
 211         pos(x, y, 0),
 212         dir(d),
 213         paths(p)
 214 { }
 215
 216
 217 TrackType::Loader::Loader(TrackType &t):
 218         DataFile::DerivedObjectLoader<TrackType, ObjectType::Loader>(t),
 219         state_bits_set(false)
 220 {
 221         add("autofit_preference", &TrackType::autofit_preference);
 222         add("object",      &TrackType::object);
 223         add("state_bits",  &Loader::state_bits);
 224         add("part",        &Loader::part);
 225 }
 226
 227 void TrackType::Loader::finish()
 228 {
 229         obj.collect_endpoints();
 230         vector<const Shape *> shapes;
 231         for(vector<TrackPart>::iterator i=obj.parts.begin(); i!=obj.parts.end(); ++i)
 232         {
 233                 i->create_shape();
 234                 shapes.push_back(&i->get_shape());
 235         }
 236         obj.shape = Geometry::Union<float, 3>::from_iterator_range(shapes.begin(), shapes.end()).clone();
 237 }
 238
 239 void TrackType::Loader::part()
 240 {
 241         TrackPart p;
 242         load_sub(p);
 243         obj.parts.push_back(p);
 244         if(!state_bits_set && p.get_path())
 245                 while(p.get_path()>=(1U<<obj.state_bits))
 246                         ++obj.state_bits;
 247 }
 248
 249 void TrackType::Loader::state_bits(unsigned b)
 250 {
 251         obj.state_bits = b;
 252         state_bits_set = true;
 253 }
 254
 255 } // namespace R2C2