using namespace std;
using namespace Msp;
+namespace {
+
+struct SetFlag
+{
+ bool &flag;
+
+ SetFlag(bool &f): flag(f) { flag = true; }
+ ~SetFlag() { flag = false; }
+};
+
+}
+
+
namespace Marklin {
Train::Train(Layout &l, const VehicleType &t, unsigned a):
loco_type(t),
address(a),
priority(0),
+ yielding_to(0),
pending_block(0),
reserving(false),
advancing(false),
priority = p;
}
+void Train::yield_to(const Train &t)
+{
+ yielding_to = &t;
+}
+
void Train::add_vehicle(const VehicleType &vt)
{
Vehicle *veh = new Vehicle(layout, vt);
next_route = 0;
end_of_route = false;
- if(route)
+ if(route && !cur_blocks.empty())
{
BlockRef &last = (rsv_blocks.empty() ? cur_blocks.back() : rsv_blocks.back());
BlockRef next = last.next();
bool Train::free_block(Block &block)
{
+ float margin = 10*layout.get_catalogue().get_scale();
+ if(get_reserved_distance_until(&block, false)<controller->get_braking_distance()*1.3+margin)
+ return false;
+
unsigned nsens = 0;
for(list<BlockRef>::iterator i=rsv_blocks.begin(); i!=rsv_blocks.end(); ++i)
{
float Train::get_reserved_distance() const
{
- Vehicle &veh = *(reverse ? vehicles.back() : vehicles.front());
- const VehicleType &vtype = veh.get_type();
-
- Track *track = veh.get_track();
- if(!track)
- return 0;
- unsigned entry = veh.get_entry();
-
- float result = -vtype.get_length()/2;
- if(reverse)
- {
- entry = track->traverse(entry);
- result += veh.get_offset();
- }
- else
- result -= veh.get_offset();
-
- bool first = true;
- list<BlockRef>::const_iterator block = cur_blocks.begin();
- while(1)
- {
- if(!first || !reverse)
- result += track->get_type().get_path_length(track->get_active_path());
- first = false;
-
- if(track->get_type().get_endpoints().size()<2)
- return result;
-
- unsigned exit = track->traverse(entry);
- Track *next = track->get_link(exit);
-
- while(!block->block->get_tracks().count(next))
- {
- ++block;
- if(block==cur_blocks.end())
- block = rsv_blocks.begin();
- if(block==rsv_blocks.end())
- return result;
- }
-
- entry = next->get_endpoint_by_link(*track);
- track = next;
- }
+ return get_reserved_distance_until(0, false);
}
void Train::tick(const Time::TimeStamp &t, const Time::TimeDelta &dt)
float d = get_real_speed(current_speed)*(dt/Time::sec);
if(ok)
{
- advancing = true;
+ SetFlag setf(advancing);
vehicle.advance(reverse ? -d : d);
- advancing = false;
}
else if(accurate_position)
{
if(!cur_blocks.empty() && !cur_blocks.front().block->get_sensor_id())
{
- Vehicle &veh = *(reverse ? vehicles.front() : vehicles.back());
-
- list<BlockRef>::iterator i = cur_blocks.begin();
- const Block::Endpoint &bep = i->block->get_endpoints()[i->entry];
-
- Track *track = bep.track;
- unsigned entry = bep.track_ep;
-
- bool found = false;
- float dist = veh.get_offset();
- if(reverse)
- dist = veh.get_track()->get_type().get_path_length(veh.get_track()->get_active_path())-dist;
- dist -= veh.get_type().get_length()/2;
- while(1)
- {
- if(track==veh.get_track())
- {
- found = true;
- break;
- }
-
- if(i!=cur_blocks.begin())
- {
- float path_len = track->get_type().get_path_length(track->get_active_path());
- dist += path_len;
- }
-
- unsigned exit = track->traverse(entry);
- Track *next = track->get_link(exit);
- entry = next->get_endpoint_by_link(*track);
- track = next;
-
- if(!i->block->get_tracks().count(track))
- {
- ++i;
- if(i==cur_blocks.end())
- break;
- }
- }
+ float dist = get_reserved_distance_until(cur_blocks.front().block, true);
- if(found && i!=cur_blocks.begin() && dist>10*layout.get_catalogue().get_scale())
+ if(dist>10*layout.get_catalogue().get_scale())
{
cur_blocks.front().block->reserve(0);
cur_blocks.erase(cur_blocks.begin());
}
}
- if(end!=cur_blocks.begin())
+ if(end!=cur_blocks.begin() && end!=cur_blocks.end())
// Free blocks up to the last inactive sensor
release_blocks(cur_blocks, cur_blocks.begin(), end);
}
if(!active)
return 0;
- BlockRef *last = 0;
+ BlockRef *start = 0;
if(!rsv_blocks.empty())
- last = &rsv_blocks.back();
+ start = &rsv_blocks.back();
else if(!cur_blocks.empty())
- last = &cur_blocks.back();
- if(!last)
+ start = &cur_blocks.back();
+ if(!start)
return 0;
pending_block = 0;
- // See how many sensor blocks we already have
+ // See how many sensor blocks and how much track we already have
unsigned nsens = 0;
+ float dist = 0;
for(list<BlockRef>::const_iterator i=rsv_blocks.begin(); i!=rsv_blocks.end(); ++i)
+ {
if(i->block->get_sensor_id())
++nsens;
+ if(nsens>0)
+ {
+ float length = 0;
+ i->block->traverse(i->entry, &length);
+ dist += length;
+ }
+ }
if(end_of_route)
return nsens;
const Route *cur_route = 0;
if(route)
{
- const set<Track *> &tracks = last->block->get_tracks();
+ const set<Track *> &tracks = start->block->get_tracks();
for(set<Track *>::const_iterator i=tracks.begin(); (cur_route!=route && i!=tracks.end()); ++i)
{
if(route->get_tracks().count(*i))
}
}
- reserving = true;
+ float approach_margin = 50*layout.get_catalogue().get_scale();
+ float min_dist = controller->get_braking_distance()*1.3+approach_margin*2;
- bool got_more = false;
- BlockRef *good = last;
+ BlockRef *last = start;
+ BlockRef *good = start;
unsigned good_sens = nsens;
- while(good_sens<3)
+ float good_dist = dist;
+ Train *blocking_train = 0;
+ std::list<BlockRef> contested_blocks;
+
+ SetFlag setf(reserving);
+
+ while(good_sens<3 || good_dist<min_dist || !contested_blocks.empty())
{
// Traverse to the next block
- unsigned exit = last->block->traverse(last->entry);
+ float length = 0;
+ unsigned exit = last->block->traverse(last->entry, cur_route, &length);
Block *link = last->block->get_link(exit);
if(!link)
break;
else if(!cur_route->get_tracks().count(entry_ep.track))
{
// Keep the blocks if we arrived at the end of the route
- good = last;
- good_sens = nsens;
- end_of_route = true;
+ if(!blocking_train)
+ {
+ good = last;
+ good_sens = nsens;
+ good_dist = dist;
+ end_of_route = true;
+ }
break;
}
}
if(link->get_endpoints().size()<2)
{
- good = last;
- good_sens = nsens;
+ if(!blocking_train)
+ {
+ good = last;
+ good_sens = nsens;
+ good_dist = dist;
+ }
break;
}
+ if(blocking_train)
+ {
+ if(link->get_train()!=blocking_train)
+ {
+ // XXX is it possible that this won't free all the blocks we want?
+ if(blocking_train->free_block(*contested_blocks.back().block))
+ {
+ // Roll back and start actually reserving the blocks
+ last = &rsv_blocks.back();
+ if(blocking_train->get_priority()==priority)
+ blocking_train->yield_to(*this);
+ blocking_train = 0;
+ continue;
+ }
+ else
+ {
+ pending_block = contested_blocks.front().block;
+ break;
+ }
+ }
+ else
+ {
+ contested_blocks.push_back(BlockRef(link, entry));
+ last = &contested_blocks.back();
+ continue;
+ }
+ }
+
bool reserved = link->reserve(this);
if(!reserved)
{
- // Ask a lesser priority train to free the block for us
- if(link->get_train()->get_priority()<priority)
- if(link->get_train()->free_block(*link))
- reserved = link->reserve(this);
+ /* We've found another train. If it wants to exit the block from the
+ same endpoint we're trying to enter from or the other way around,
+ treat it as coming towards us. Otherwise treat it as going in the
+ same direction. */
+ Train *other_train = link->get_train();
+ int other_entry = other_train->get_entry_to_block(*link);
+ if(other_entry<0)
+ throw LogicError("Block reservation inconsistency");
+
+ int other_prio = other_train->get_priority();
+
+ bool entry_conflict = (static_cast<unsigned>(entry)==link->traverse(other_entry));
+ bool exit_conflict = (link->traverse(entry)==static_cast<unsigned>(other_entry));
+ if(!entry_conflict && !exit_conflict)
+ {
+ /* Same direction, keep the blocks we got so far and wait for the
+ other train to pass */
+ good = last;
+ good_sens = nsens;
+ good_dist = dist;
+
+ // Ask a lesser priority train to free the block for us
+ if(other_train->get_priority()<priority)
+ if(other_train->free_block(*link))
+ reserved = link->reserve(this);
+ }
+ else if(other_prio<priority || (other_prio==priority && other_train!=yielding_to && entry_conflict))
+ {
+ /* A lesser priority train is coming at us, we must ask it to free
+ enough blocks to get clear of it to avoid a potential deadlock */
+ blocking_train = other_train;
+ contested_blocks.clear();
+ contested_blocks.push_back(BlockRef(link, entry));
+ last = &contested_blocks.back();
+ continue;
+ }
if(!reserved)
{
- // If we found another train and it's not headed straight for us, we can keep the blocks we got
- int other_entry = link->get_train()->get_entry_to_block(*link);
- if(other_entry<0)
- throw LogicError("Block reservation inconsistency");
- if(static_cast<unsigned>(entry)!=link->traverse(other_entry))
- {
- good = last;
- good_sens = nsens;
- }
pending_block = link;
break;
}
// Keep the blocks reserved so far, as either us or the other train can diverge
good = last;
good_sens = nsens;
+ good_dist = dist;
// Figure out what path we'd like to take on the turnout
int path = -1;
}
}
+ if(!contested_blocks.empty() && contested_blocks.front().block==link)
+ contested_blocks.pop_front();
+
rsv_blocks.push_back(BlockRef(link, entry));
last = &rsv_blocks.back();
if(last->block->get_sensor_id())
- {
++nsens;
- got_more = true;
- }
+ if(nsens>0)
+ dist += length;
}
// Unreserve blocks that were not good
- while(!rsv_blocks.empty() && last!=good)
+ while(!rsv_blocks.empty() && &rsv_blocks.back()!=good)
{
- last->block->reserve(0);
+ rsv_blocks.back().block->reserve(0);
rsv_blocks.erase(--rsv_blocks.end());
- if(!rsv_blocks.empty())
- last = &rsv_blocks.back();
}
- reserving = false;
+ if(!rsv_blocks.empty() && &rsv_blocks.back()!=start)
+ // We got some new blocks, so no longer need to yield
+ yielding_to = 0;
// Make any sensorless blocks at the beginning immediately current
list<BlockRef>::iterator i;
return good_sens;
}
+float Train::get_reserved_distance_until(const Block *until_block, bool back) const
+{
+ if(cur_blocks.empty())
+ return 0;
+
+ Vehicle &veh = *(reverse!=back ? vehicles.back() : vehicles.front());
+ const VehicleType &vtype = veh.get_type();
+
+ Track *track = veh.get_track();
+ if(!track)
+ return 0;
+
+ list<BlockRef>::const_iterator block = cur_blocks.begin();
+ while(block!=cur_blocks.end() && !block->block->get_tracks().count(track))
+ ++block;
+ if(block==cur_blocks.end() || block->block==until_block)
+ return 0;
+
+ unsigned entry = veh.get_entry();
+
+ float result = veh.get_offset();
+ if(reverse!=back)
+ entry = track->traverse(entry);
+ else
+ result = track->get_type().get_path_length(track->get_active_path())-result;
+ result -= vtype.get_length()/2;
+
+ while(1)
+ {
+ if(track->get_type().get_endpoints().size()<2)
+ break;
+
+ Track *next = track->get_link(track->traverse(entry));
+
+ if(!block->block->get_tracks().count(next))
+ {
+ if(back)
+ {
+ if(block==cur_blocks.begin())
+ break;
+ --block;
+ }
+ else
+ {
+ ++block;
+ if(block==cur_blocks.end())
+ block = rsv_blocks.begin();
+ if(block==rsv_blocks.end())
+ break;
+ }
+
+ if(block->block==until_block)
+ break;
+ }
+
+ entry = next->get_endpoint_by_link(*track);
+ track = next;
+
+ result += track->get_type().get_path_length(track->get_active_path());
+ }
+
+ return result;
+}
+
float Train::get_real_speed(unsigned i) const
{
if(real_speed[i].weight)