FGraphAStar

Generic graph A* implementation

TGraph holds graph representation. Needs to implement functions: bool IsValidRef(FNodeRef NodeRef) const; - returns whether given node identyfication is correct FNodeRef GetNeighbour(const FSearchNode& NodeRef, const int32 NeighbourIndex) const; - returns neighbour ref

it also needs to specify node type FNodeRef - type used as identification of nodes in the graph

TQueryFilter (FindPath's parameter) filter class is what decides which graph edges can be used and at what cost. It needs to implement following functions: float GetHeuristicScale() const; - used as GetHeuristicCost's multiplier float GetHeuristicCost(const FSearchNode& StartNode, const FSearchNode& EndNode) const; - estimate of cost from StartNode to EndNode from a search node float GetTraversalCost(const FSearchNode& StartNode, const FSearchNode& EndNode) const; - real cost of traveling from StartNode directly to EndNode from a search node bool IsTraversalAllowed(const FNodeRef NodeA, const FNodeRef NodeB) const; - whether traversing given edge is allowed from a NodeRef bool WantsPartialSolution() const; - whether to accept solutions that do not reach the goal

Backward compatible methods, please use the FSearchNode version. If the FSearchNode version are implemented, these methods will not be called at all. FNodeRef GetNeighbour(const FNodeRef NodeRef, const int32 NeighbourIndex) const; - returns neighbour ref float GetHeuristicCost(const FNodeRef StartNodeRef, const FNodeRef EndNodeRef) const; - estimate of cost from StartNode to EndNode from a NodeRef float GetTraversalCost(const FNodeRef StartNodeRef, const FNodeRef EndNodeRef) const; - real cost of traveling from StartNode directly to EndNode from a NodeRef

Optionally implemented methods to parameterize the search int32 GetNeighbourCount(FNodeRef NodeRef) const; - returns number of neighbours that the graph node identified with NodeRef has, it is ok if not implemented, the logic will stop calling GetNeighbour once it received an invalid noderef bool ShouldIgnoreClosedNodes() const; - whether to revisit closed node or not bool ShouldIncludeStartNodeInPath() const; - whether to put the start node in the resulting path int32 GetMaxSearchNodes() const; - whether to limit the number of search node to a maximum float GetCostLimit() constk - whether to limit the search to a maximum cost