internal RoadCollection(RoadTopology topology, AssetLoadContext loadContext, HeightMap heightMap)
: this()
{
// The map stores road segments with no connectivity:
// - a segment is from point A to point B
// - with a road type name
// - and start and end curve types (angled, tight curve, broad curve).
// The goal is to create road networks of connected road segments,
// where a network has only a single road type.
// A road network is composed of 2 or more nodes.
// A network is a (potentially) cyclic graph.
// A road node has > 1 and <= 4 edges connected to it.
// A node can be part of multiple networks.
// An edge can only exist in one network.
var roadTemplateList = new RoadTemplateList(loadContext.AssetStore.RoadTemplates);
var networks = RoadNetwork.BuildNetworks(topology, roadTemplateList);
foreach (var network in networks)
{
_roads.Add(AddDisposable(new Road(
loadContext,
heightMap,
network)));
}
}
public static IEnumerable <RoadNetwork> BuildNetworks(RoadTopology topology, RoadTemplateList roadTemplateList)
{
topology.AlignOrientation();
var edgeSegments = BuildEdgeSegments(topology);
InsertNodeSegments(topology, edgeSegments);
InsertEndCapSegments(edgeSegments, roadTemplateList);
var networks = BuildNetworks(topology, edgeSegments);
// sort networks in the order specified by roadTemplateList
var sortedNetworks = roadTemplateList
.Join(
networks,
t => t.InstanceId,
n => n.Template.InstanceId,
(t, n) => n);
return(sortedNetworks);
}
private static void InsertEndCapSegments(IReadOnlyDictionary <RoadTopologyEdge, StraightRoadSegment> edgeSegments, RoadTemplateList roadTemplateList)
{
foreach (var edge in edgeSegments.Reverse())
{
// the end cap flag is only relevant when the edge is not connected to another edge on this end
bool hasEndCapAtStart = edge.Key.StartType.HasFlag(RoadType.EndCap) && edge.Value.Start.To == null;
bool hasEndCapAtEnd = edge.Key.EndType.HasFlag(RoadType.EndCap) && edge.Value.End.To == null;
// single edges without any connected edges can only have one end cap (at the end position), even when the flag is present at both nodes
if (hasEndCapAtEnd)
{
EndCapRoadSegment.CreateEndCap(GetIncomingRoadData(edge.Key.End, edge.Key), edge.Value.EndPosition, edge.Key.Template, edgeSegments, roadTemplateList);
}
else if (hasEndCapAtStart)
{
EndCapRoadSegment.CreateEndCap(GetIncomingRoadData(edge.Key.Start, edge.Key), edge.Value.StartPosition, edge.Key.Template, edgeSegments, roadTemplateList);
}
}
}
