/* * Check if two edges collide with eachother. */ public static bool EdgesCollide(Edge edge1, Edge edge2, NodeGraph nodeGraph1, NodeGraph nodeGraph2) { // Set up Edge1 Node edge1Node1 = nodeGraph1.GetNode(edge1.nodeIndex1); Node edge1Node2 = nodeGraph1.GetNode(edge1.nodeIndex2); Vect3 edge1Forward = (edge1Node2.coordinate - edge1Node1.coordinate).GetNormalized(); Vect3 edge1Right = Vect3.Cross(edge1Forward, Vect3.Up).GetNormalized(); Vect3 edge1Up = Vect3.Cross(edge1Right, edge1Forward).GetNormalized(); AxisBBox bBox1 = GetEdgeBoundingBox(edge1, edge1Node1.coordinate, edge1Node2.coordinate, edge1Right, edge1Up); // Set up Edge2 Node edge2Node1 = nodeGraph2.GetNode(edge2.nodeIndex1); Node edge2Node2 = nodeGraph2.GetNode(edge2.nodeIndex2); Vect3 edge2Forward = (edge2Node2.coordinate - edge2Node1.coordinate).GetNormalized(); Vect3 edge2Right = Vect3.Cross(edge2Forward, Vect3.Up).GetNormalized(); Vect3 edge2Up = Vect3.Cross(edge2Right, edge2Forward).GetNormalized(); AxisBBox bBox2 = GetEdgeBoundingBox(edge2, edge2Node1.coordinate, edge2Node2.coordinate, edge2Right, edge2Up); // Check BoundingBoxes if (bBox1.Overlaps(bBox2)) { if (IsParallel2D((edge1Node1.coordinate.x, edge1Node1.coordinate.z), (edge1Node2.coordinate.x, edge1Node2.coordinate.z), (edge2Node1.coordinate.x, edge2Node1.coordinate.z), (edge2Node2.coordinate.x, edge2Node2.coordinate.z))) { return(ParallelEdgesCollide(edge1, edge2, nodeGraph1, nodeGraph2)); } else { Vect3 edge1RightWall1 = edge1Node1.coordinate + ((edge1.width / 2) * edge1Right); Vect3 edge1RightWall2 = edge1Node2.coordinate + ((edge1.width / 2) * edge1Right); Vect3 edge2RightWall1 = edge2Node1.coordinate + ((edge2.width / 2) * edge2Right); Vect3 edge2RightWall2 = edge2Node2.coordinate + ((edge2.width / 2) * edge2Right); Vect3 edge1LeftWall1 = edge1Node1.coordinate - ((edge1.width / 2) * edge1Right); Vect3 edge1LeftWall2 = edge1Node2.coordinate - ((edge1.width / 2) * edge1Right); Vect3 edge2LeftWall1 = edge2Node1.coordinate - ((edge2.width / 2) * edge2Right); Vect3 edge2LeftWall2 = edge2Node2.coordinate - ((edge2.width / 2) * edge2Right); // Check all Possible wall collisions. return(WallsIntersect(edge1, edge2, edge1RightWall1, edge1RightWall2, edge2RightWall1, edge2RightWall2) || WallsIntersect(edge1, edge2, edge1RightWall1, edge1RightWall2, edge2LeftWall1, edge2LeftWall2) || WallsIntersect(edge1, edge2, edge1LeftWall1, edge1LeftWall2, edge2RightWall1, edge2RightWall2) || WallsIntersect(edge1, edge2, edge1LeftWall1, edge1LeftWall2, edge2LeftWall1, edge2LeftWall2) || WallsIntersect(edge1, edge2, edge1RightWall1, edge1LeftWall1, edge2RightWall1, edge2RightWall2) || WallsIntersect(edge1, edge2, edge1RightWall1, edge1LeftWall1, edge2LeftWall1, edge2LeftWall2) || WallsIntersect(edge1, edge2, edge1RightWall2, edge1LeftWall2, edge2RightWall1, edge2RightWall2) || WallsIntersect(edge1, edge2, edge1RightWall2, edge1LeftWall2, edge2LeftWall1, edge2LeftWall2) || WallsIntersect(edge1, edge2, edge1RightWall1, edge1RightWall2, edge2RightWall1, edge2LeftWall1) || WallsIntersect(edge1, edge2, edge1RightWall1, edge1RightWall2, edge2RightWall2, edge2LeftWall2) || WallsIntersect(edge1, edge2, edge1LeftWall1, edge1LeftWall2, edge2RightWall1, edge2LeftWall1) || WallsIntersect(edge1, edge2, edge1LeftWall1, edge1LeftWall2, edge2RightWall2, edge2LeftWall2) || WallsIntersect(edge1, edge2, edge1RightWall1, edge1LeftWall1, edge2RightWall1, edge2LeftWall1) || WallsIntersect(edge1, edge2, edge1RightWall1, edge1LeftWall1, edge2RightWall2, edge2LeftWall2) || WallsIntersect(edge1, edge2, edge1RightWall2, edge1LeftWall2, edge2RightWall1, edge2LeftWall1) || WallsIntersect(edge1, edge2, edge1RightWall2, edge1LeftWall2, edge2RightWall2, edge2LeftWall2)); } }
private static NodeGraph MergeNodeGraph(NodeGraph nodeGraph, VoxelGrid voxelGrid) { bool proximity = true; while (proximity) { proximity = false; Edge mergableEdge = null; foreach (Edge edge in nodeGraph.Edges) { if ((nodeGraph.GetCoordinateOfNode(edge.nodeIndex1) - nodeGraph.GetCoordinateOfNode(edge.nodeIndex2)).Length() < mergeThreshold * voxelGrid.resolution) { mergableEdge = edge; proximity = true; break; } } if (mergableEdge != null) { Vect3 centerPoint = (nodeGraph.GetCoordinateOfNode(mergableEdge.nodeIndex1) + nodeGraph.GetCoordinateOfNode(mergableEdge.nodeIndex2)) / 2d; nodeGraph.MoveNode(nodeGraph.GetNode(mergableEdge.nodeIndex1), centerPoint); nodeGraph.MoveNode(nodeGraph.GetNode(mergableEdge.nodeIndex2), centerPoint); } } nodeGraph.ReIndexNodeGraph(); return(nodeGraph); }
/* * Takes in a list of nodeGraphs and unify them into one nodeGraph. */ public static NodeGraph UnifyGraphs(List <NodeGraph> unifyingGraphs) { NodeGraph baseGraph = unifyingGraphs[0]; unifyingGraphs.Remove(baseGraph); // Define Variables var joiningEdges = new Stack <Edge>(); int newNodeIndex1; int newNodeIndex2; Edge joiningEdge; Edge baseEdge; var edgesAdded = new List <Edge>(); Vect3 collisionPoint; int baseNodeIndex; int extraJoiningNodeIndex; Edge extraJoiningEdge1; Edge extraJoiningEdge2; // Unify each graph with the base graph foreach (NodeGraph joiningGraph in unifyingGraphs) { // Fill edge stack of joining edges joiningEdges.Clear(); for (int i = joiningGraph.Edges.Count - 1; i >= 0; i--) { joiningEdges.Push(joiningGraph.GetEdge(i)); } newNodeIndex1 = -1; newNodeIndex2 = -1; edgesAdded.Clear(); // Join edges LOOP // Find which node indexes that the edge should have. // If -1 a new node needs to be created. while (joiningEdges.Count > 0) { joiningEdge = joiningEdges.Pop(); newNodeIndex2 = newNodeIndex1; newNodeIndex1 = -1; for (int i = 0; i < baseGraph.Edges.Count; i++) { baseEdge = baseGraph.GetEdge(i); if (baseEdge == null || edgesAdded.Contains(baseEdge)) { continue; } // If base edge and joining edge has a collision, find where on the base graph the collision is. // To find out if a new node needs to be created or of the graph should join an exisiting node. if (EdgesCollide(baseEdge, joiningEdge, baseGraph, joiningGraph)) { collisionPoint = GetEdgesCollidingPoint(baseEdge, joiningEdge, baseGraph, joiningGraph); if (collisionPoint != null) { if (joiningGraph.PointCloseToNode(collisionPoint, joiningGraph.GetNode(joiningEdge.nodeIndex1))) { baseNodeIndex = baseGraph.GetCollisionNodeIndex(collisionPoint, baseEdge); if (newNodeIndex1 == -1) { newNodeIndex1 = baseNodeIndex; } else if (newNodeIndex1 != baseNodeIndex) { newNodeIndex1 = baseGraph.UnifyNodes(baseGraph.GetNode(newNodeIndex1), baseGraph.GetNode(baseNodeIndex)).index; baseGraph.MoveNode(baseGraph.GetNode(newNodeIndex1), baseGraph.GetNode(baseNodeIndex).coordinate); } } else if (joiningGraph.PointCloseToNode(collisionPoint, joiningGraph.GetNode(joiningEdge.nodeIndex2))) { baseNodeIndex = baseGraph.GetCollisionNodeIndex(collisionPoint, baseEdge); if (newNodeIndex2 == -1) { newNodeIndex2 = baseNodeIndex; } else if (newNodeIndex2 != baseNodeIndex) { newNodeIndex2 = baseGraph.UnifyNodes(baseGraph.GetNode(newNodeIndex2), baseGraph.GetNode(baseNodeIndex)).index; } } else if (joiningGraph.PointOnEdge(collisionPoint, joiningEdge)) { joiningGraph.AddNode(collisionPoint); extraJoiningNodeIndex = joiningGraph.GetNode(collisionPoint).index; extraJoiningEdge1 = joiningGraph.AddEdge(joiningEdge.nodeIndex1, extraJoiningNodeIndex, joiningEdge.width, joiningEdge.height); extraJoiningEdge2 = joiningGraph.AddEdge(extraJoiningNodeIndex, joiningEdge.nodeIndex2, joiningEdge.width, joiningEdge.height); joiningEdge = extraJoiningEdge2; joiningEdges.Push(extraJoiningEdge1); baseNodeIndex = baseGraph.GetCollisionNodeIndex(collisionPoint, baseEdge); newNodeIndex1 = baseNodeIndex; } } } } // After base graph edge loop. Add Edge to base graph correctly. if (newNodeIndex1 == -1) { baseGraph.AddNode(joiningGraph.GetNode(joiningEdge.nodeIndex1)); newNodeIndex1 = baseGraph.GetNode(joiningGraph.GetNode(joiningEdge.nodeIndex1).coordinate).index; } if (newNodeIndex2 == -1) { baseGraph.AddNode(joiningGraph.GetNode(joiningEdge.nodeIndex2)); newNodeIndex2 = baseGraph.GetNode(joiningGraph.GetNode(joiningEdge.nodeIndex2).coordinate).index; } if (newNodeIndex1 == newNodeIndex2) { throw new Exception("Same new node index, " + newNodeIndex1); } edgesAdded.Add(baseGraph.AddEdge(newNodeIndex1, newNodeIndex2, joiningEdge.width, joiningEdge.height)); } baseGraph.ReIndexNodeGraph(); } return(baseGraph); }
/** * Generates a NodeGraph from a skeletonized voxelgrid, by traversing neighboring * voxels and creating nodes connected by edges to maintain the topology of the voxelgrid. */ private static NodeGraph CreateNodeGraph(DistanceGrid distanceGrid, VoxelGrid voxelGrid) { bool[][][] visitedGrid = new bool[distanceGrid.xBound + 1][][]; for (int i = 0; i < visitedGrid.Length; i++) { visitedGrid[i] = new bool[distanceGrid.yBound + 1][]; for (int j = 0; j < visitedGrid[i].Length; j++) { visitedGrid[i][j] = new bool[distanceGrid.zBound + 1]; } } NodeGraph nodeGraph = new NodeGraph(); Queue <(Point3, Point3)> startPoints = GetStartPoints(distanceGrid); Point3 initialPoint = startPoints.Peek().Item1; nodeGraph.AddNode(voxelGrid.LowestPositionAtCoordinate(initialPoint)); visitedGrid[initialPoint.x][initialPoint.y][initialPoint.z] = true; //Breadth-first traversing of the Voxels while (startPoints.Count > 0) { (Point3 startPoint, Point3 currentPoint) = startPoints.Dequeue(); //Special case for when connecting to an allready visited node if (visitedGrid[currentPoint.x][currentPoint.y][currentPoint.z]) { Vect3 pos1 = voxelGrid.LowestPositionAtCoordinate(startPoint); Vect3 pos2 = voxelGrid.LowestPositionAtCoordinate(currentPoint); Node startNode = nodeGraph.GetNode(pos1); Node currentNode = nodeGraph.GetNode(pos2); if (nodeGraph.GetNode(pos1) == null || nodeGraph.GetNode(pos2) == null) { continue; } bool shouldLink = true; foreach (var neighbor in currentNode.neighbors) { if (neighbor.nodeIndex == startNode.index) { shouldLink = false; } else { Node neighborNode = nodeGraph.GetNode(neighbor.nodeIndex); foreach (var nextNeighbor in neighborNode.neighbors) { if (nextNeighbor.nodeIndex == startNode.index) { shouldLink = false; } } } if (!shouldLink) { break; } } if (shouldLink) { nodeGraph.LinkNodes(pos1, pos2); } else { continue; } } Point3 cameFrom = startPoint; List <Point3> pathPoints = new List <Point3>() { startPoint }; Vect3 startCoordinate = voxelGrid.LowestPositionAtCoordinate(startPoint); Vect3 currentCoordinate = voxelGrid.LowestPositionAtCoordinate(currentPoint); List <Vect3> intermediateCoords = new List <Vect3>(); List <Point3> neighbors = new List <Point3>(); bool distanceWasValid = false; //Traversing untill the Nodeplacement would make the Edge to far away from the voxels it represents, //an already visited node is reached, an intersection is found or it's a dead end. while (DistancesAreValid(startCoordinate, currentCoordinate, intermediateCoords, voxelGrid.resolution)) { // Node we found was visited if (visitedGrid[currentPoint.x][currentPoint.y][currentPoint.z]) { // Ensures nothing happens after we break distanceWasValid = true; break; } neighbors = distanceGrid.Get26AdjacentNeighbors(currentPoint); pathPoints.Add(currentPoint); if (neighbors.Count != 2) { visitedGrid[currentPoint.x][currentPoint.y][currentPoint.z] = true; distanceWasValid = true; break; } // Only one new neighbor intermediateCoords.Add(voxelGrid.LowestPositionAtCoordinate(currentPoint)); Point3 temp = currentPoint; currentPoint = neighbors[0] == cameFrom ? neighbors[1] : neighbors[0]; currentCoordinate = voxelGrid.LowestPositionAtCoordinate(currentPoint); cameFrom = temp; visitedGrid[cameFrom.x][cameFrom.y][cameFrom.z] = true; } double maxDistanceValue = 0; foreach (var point in pathPoints) { maxDistanceValue += distanceGrid.grid[point.x][point.y][point.z] * voxelGrid.resolution * SquareRootOfThree; // Distance is 26-distance from edge // double distanceValue = distanceGrid.grid[point.x][point.y][point.z]*voxelGrid.resolution*2; // maxDistanceValue = distanceValue > maxDistanceValue ? distanceValue : maxDistanceValue; } maxDistanceValue /= (double)pathPoints.Count; double minWidth = maxDistanceValue; double minHeight = maxDistanceValue; if (!distanceWasValid) { nodeGraph.AddNode(intermediateCoords[intermediateCoords.Count - 1], minWidth, minHeight, nodeGraph.GetNode(startCoordinate).index); visitedGrid[cameFrom.x][cameFrom.y][cameFrom.z] = true; if (!visitedGrid[currentPoint.x][currentPoint.y][currentPoint.z]) { startPoints.Enqueue((cameFrom, currentPoint)); } } else { nodeGraph.AddNode(currentCoordinate, minWidth, minHeight, nodeGraph.GetNode(startCoordinate).index); foreach (var neighbor in neighbors) { if (neighbor == cameFrom || visitedGrid[neighbor.x][neighbor.y][neighbor.z]) { continue; } startPoints.Enqueue((currentPoint, neighbor)); } } } return(nodeGraph); }