// Finds and returns the path between source and target indices
// and the spanning tree of the search.
//
// Returns true if a path exists, returns false otherwise.
//
// TODO Replace ref with in if one day Unity supports C# 7+
protected override bool FindPath(
int sourceIndex, int targetIndex,
AbstractGraph <NodeType, EdgeType> sourceGraph,
ref List <int> path,
ref List <HelperEdge> spanningTree
)
{
HelperEdge startEdge = new HelperEdge(sourceIndex, sourceIndex, EdgeCommons.DefaultEdgeCost);
searchQueue.Enqueue(startEdge);
visitingList[sourceIndex] = GraphSearchCommons.SearchFlags.visited;
// Search
while (searchQueue.Count > 0)
{
// Get the next element in the queue
HelperEdge next = searchQueue.Dequeue();
// Mark for the route
route[next.ToNode] = next.FromNode;
// Add into the spanning tree
if (next != startEdge)
{
spanningTree.Add(next);
}
// The target has found
if (next.ToNode == targetIndex)
{
GetTargetPath(sourceIndex, targetIndex, ref path);
return(true);
}
List <HelperEdge> edgeList = sourceGraph.GetLeadingEdges(next.ToNode);
if (edgeList.Count > 0)
{
foreach (HelperEdge edge in edgeList)
{
// Push each path leading to an unvisited node
if (visitingList[edge.ToNode] == GraphSearchCommons.SearchFlags.unvisited)
{
// Push each path leading to an unvisited node
searchQueue.Enqueue(edge);
// And mark it as visited
visitingList[edge.ToNode] = GraphSearchCommons.SearchFlags.visited;
}
}
}
} // End of while
// No path to the target
return(false);
}
public override bool Equals(object obj)
{
if (obj == null || GetType() != obj.GetType())
{
return(false);
}
HelperEdge edge = (HelperEdge)obj;
return(this == edge);
}
// Returns the all possible paths from given node
// Serves to path finding algorithms
public override List <HelperEdge> GetLeadingEdges(int nodeIndex)
{
List <HelperEdge> edgeList = new List <HelperEdge>();
foreach (var edgeId in adjacencyList[nodeIndex])
{
HelperEdge newEdge = new HelperEdge(nodeIndex, edgeId, 0f);
edgeList.Add(newEdge);
}
return(edgeList);
}
// Returns the all possible paths from given node
// Serves to path finding algorithms
public override List <HelperEdge> GetLeadingEdges(int nodeIndex)
{
List <HelperEdge> edgeList = new List <HelperEdge>();
foreach (EdgeType edge in this.edges[nodeIndex])
{
HelperEdge newEdge = new HelperEdge(edge.FromNode, edge.ToNode, 0f);
edgeList.Add(newEdge);
}
return(edgeList);
}
// Finds and returns the path between source and target indices.
//
// Returns true if a path exists, returns false otherwise.
//
// TODO Replace ref with in if one day Unity supports C# 7+
protected override bool FindPath(
int sourceIndex, int targetIndex,
AbstractGraph <NodeType, EdgeType> sourceGraph,
ref List <int> path
)
{
HelperEdge startEdge = new HelperEdge(sourceIndex, sourceIndex, EdgeCommons.DefaultEdgeCost);
searchStack.Push(startEdge);
// Search
while (searchStack.Count > 0)
{
// Get the top element of the stack
//EdgeType next = searchStack.Peek();
HelperEdge next = searchStack.Peek();
searchStack.Pop();
// Mark for the route
route[next.ToNode] = next.FromNode;
// And mark as visited
visitingList[next.ToNode] = GraphSearchCommons.SearchFlags.visited;
// The target has found
if (next.ToNode == targetIndex)
{
GetTargetPath(sourceIndex, targetIndex, ref path);
return(true);
}
List <HelperEdge> edgeList = sourceGraph.GetLeadingEdges(next.ToNode);
if (edgeList.Count > 0)
{
foreach (HelperEdge edge in edgeList)
{
// Push each path leading to an unvisited node
if (visitingList[edge.ToNode] == GraphSearchCommons.SearchFlags.unvisited)
{
searchStack.Push(edge);
}
}
}
} // End of while()
// No path to the target
return(false);
}
