internal static int FindCurrent(NativeMinHeap minSet, NativeArray <byte> closeSet) { _markerFindCurrent.Begin(); while (minSet.HasNext()) { _markerPop.Begin(); var next = minSet.Pop(); _markerPop.End(); // Check if this is not visited tile if (closeSet[next.Position] == 0) { _markerFindCurrent.End(); return(next.Position); } } _markerFindCurrent.End(); return(-1); }
public void Execute(Entity entity, int index, ref PathFindingRequest request) { _iterations = 0; _pathNodeCount = 0; //Generate Working Containers var openSet = new NativeMinHeap(MapSize, Allocator.Temp); var cameFrom = new NativeArray <int>(MapSize, Allocator.Temp); var costCount = new NativeArray <int>(MapSize, Allocator.Temp); for (var i = 0; i < MapSize; i++) { costCount[i] = int.MaxValue; } // Path finding var startId = request.StartId; var goalId = request.GoalId; openSet.Push(new MinHeapNode(startId, 0)); costCount[startId] = 0; var currentId = -1; while (_iterations < IterationLimit && openSet.HasNext()) { var currentNode = openSet[openSet.Pop()]; currentId = currentNode.Id; if (currentId == goalId) { break; } var neighboursId = new NativeList <int>(4, Allocator.Temp); Nodes[currentId].GetNeighbours(ref neighboursId); foreach (var neighbourId in neighboursId) { //if cost == -1 means obstacle, skip if (Nodes[neighbourId].GetCost() == -1) { continue; } var currentCost = costCount[currentId] == int.MaxValue ? 0 : costCount[currentId]; var newCost = currentCost + Nodes[neighbourId].GetCost(); //not better, skip if (costCount[neighbourId] <= newCost) { continue; } var priority = newCost + Nodes[neighbourId].Heuristic(goalId); openSet.Push(new MinHeapNode(neighbourId, priority)); cameFrom[neighbourId] = currentId; costCount[neighbourId] = newCost; } _iterations++; neighboursId.Dispose(); } //Construct path var buffer = ResultECB.AddBuffer <PathRoute>(index, entity); var nodeId = goalId; while (_pathNodeCount < PathNodeLimit && !nodeId.Equals(startId)) { buffer.Add(new PathRoute { Id = nodeId }); nodeId = cameFrom[nodeId]; _pathNodeCount++; } //Construct Result var success = true; var log = new NativeString64("Path finding success"); if (!openSet.HasNext() && currentId != goalId) { success = false; log = new NativeString64("Out of openset"); } if (_iterations >= IterationLimit && currentId != goalId) { success = false; log = new NativeString64("Iteration limit reached"); } else if (_pathNodeCount >= PathNodeLimit && !nodeId.Equals(startId)) { success = false; log = new NativeString64("Step limit reached"); } ResultECB.AddComponent(index, entity, new PathResult { Success = success, Log = log }); //Clean result at end of simulation CleanECB.DestroyEntity(index, entity); //Clear openSet.Dispose(); cameFrom.Dispose(); costCount.Dispose(); }
private void FindPath(int2 startPosition, int2 endPosition) { Debug.Log("Pathfinding to: " + endPosition); if (startPosition.Equals(endPosition) || Grid[GetIndex(endPosition)] == -1) { Debug.LogError("asking to go into an obstacle, or is already there!"); foundPath = false; return; } PathNode head = new PathNode(startPosition, CalculateDistanceCost(startPosition, endPosition)); OpenSet.Push(head); while (itterationLimit > 0 && OpenSet.HasNext()) { int currentIndex = OpenSet.Pop(); PathNode current = OpenSet[currentIndex]; int ind = GetIndex(current.Position); PathNode cameFromNode = CameFrom[ind]; if (current.Position.Equals(endPosition)) { //Found our destination, we will let the cleanup job handle the path reconstruction for now //ReconstructPath(startPosition, endPosition); return; } float initialCost = CostSoFar[GetIndex(current.Position)]; PathNode[] neighbourNodes = new PathNode[Neighbours.Length]; for (int i = 0; i < Neighbours.Length; i++) { int2 neighbour = Neighbours[i]; int2 position = current.Position + neighbour; if (position.x < 0 || position.x >= DimX || position.y < 0 || position.y >= DimY) { continue; } int index = GetIndex(position); float cellCost = GetCellCost(currentIndex, index, true); if (float.IsInfinity(cellCost)) { current.NextToObstacle = true; continue; } neighbourNodes[i] = new PathNode(position, cellCost); } if (!cameFromNode.Equals(null) && cameFromNode.NextToObstacle && current.NextToObstacle && IsDiagonal(current.Position, cameFromNode.Position)) { //In this case, the path came from point that was next to a obstacle, and is moving diagonally towards a point next to an obstacle. so we are assuming they are moving diagonally through the obstacle //TODO: this is not always the case, will need to resolve later continue; } for (int i = 0; i < neighbourNodes.Length; i++) { int2 neighbour = Neighbours[i]; PathNode neighbourNode = neighbourNodes[i]; int index = GetIndex(neighbourNode.Position); if (neighbourNode.Equals(null)) { Debug.Log("neighbour null"); continue; } float neighbourCost = 10; if ((math.abs(neighbour.x) + math.abs(neighbour.y)) == 2) { neighbourCost = 14; } float newCost = initialCost + neighbourCost + neighbourNode.ExpectedCost; float oldCost = CostSoFar[index]; if (!(oldCost <= 0) && !(newCost < oldCost)) { continue; } CostSoFar[index] = newCost; CameFrom[index] = current; neighbourNode.ExpectedCost = newCost + CalculateDistanceCost(neighbourNode.Position, endPosition); OpenSet.Push(neighbourNode); } itterationLimit--; } if (OpenSet.HasNext()) { //We ran out of itterations //We will just give out where we stapped at for now //TODO: fix this var currentIndex = OpenSet.Pop(); endPosition = OpenSet[currentIndex].Position; } }