source/libr2c2/tracktype.cpp

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