Added KD tree

Runtime/KDTree/KDQuery/QueryInterval.cs

@@ -0,0 +1,151 @@
+/*MIT License
+
+Copyright(c) 2018 Vili Volčini / viliwonka
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+using System.Collections.Generic;
+using UnityEngine;
+using System;
+
+namespace DataStructures.ViliWonka.KDTree {
+
+    public partial class KDQuery {
+
+        public void Interval(KDTree tree, Vector3 min, Vector3 max, List<int> resultIndices) {
+
+            Reset();
+
+            Vector3[] points = tree.Points;
+            int[] permutation = tree.Permutation;
+
+            var rootNode = tree.RootNode;
+
+            PushToQueue(
+
+                rootNode,
+                rootNode.bounds.ClosestPoint((min + max) / 2)
+            );
+
+            KDQueryNode queryNode = null;
+            KDNode node = null;
+
+
+            // KD search with pruning (don't visit areas which distance is more away than range)
+            // Recursion done on Stack
+            while(LeftToProcess > 0) {
+
+                queryNode = PopFromQueue();
+                node = queryNode.node;
+
+                if(!node.Leaf) {
+
+                    int partitionAxis = node.partitionAxis;
+                    float partitionCoord = node.partitionCoordinate;
+
+                    Vector3 tempClosestPoint = queryNode.tempClosestPoint;
+
+                    if((tempClosestPoint[partitionAxis] - partitionCoord) < 0) {
+
+                        // we already know we are inside negative bound/node,
+                        // so we don't need to test for distance
+                        // push to stack for later querying
+
+                        // tempClosestPoint is inside negative side
+                        // assign it to negativeChild
+                        PushToQueue(node.negativeChild, tempClosestPoint);
+
+                        tempClosestPoint[partitionAxis] = partitionCoord;
+
+                        // testing other side
+                        if(node.positiveChild.Count != 0
+                        && tempClosestPoint[partitionAxis] <= max[partitionAxis]) {
+
+                            PushToQueue(node.positiveChild, tempClosestPoint);
+                        }
+                    }
+                    else {
+
+                        // we already know we are inside positive bound/node,
+                        // so we don't need to test for distance
+                        // push to stack for later querying
+
+                        // tempClosestPoint is inside positive side
+                        // assign it to positiveChild
+                        PushToQueue(node.positiveChild, tempClosestPoint);
+
+                        // project the tempClosestPoint to other bound
+                        tempClosestPoint[partitionAxis] = partitionCoord;
+
+                        // testing other side
+                        if(node.negativeChild.Count != 0
+                        && tempClosestPoint[partitionAxis] >= min[partitionAxis]) {
+
+                            PushToQueue(node.negativeChild, tempClosestPoint);
+                        }
+                    }
+                }
+                else {
+
+                    // LEAF
+
+                    // testing if node bounds are inside the query interval
+                    if(node.bounds.min[0] >= min[0]
+                    && node.bounds.min[1] >= min[1]
+                    && node.bounds.min[2] >= min[2]
+
+                    && node.bounds.max[0] <= max[0]
+                    && node.bounds.max[1] <= max[1]
+                    && node.bounds.max[2] <= max[2]) {
+
+                        for(int i = node.start; i < node.end; i++) {
+
+                            resultIndices.Add(permutation[i]);
+                        }
+
+                    }
+                    // node is not inside query interval, need to do test on each point separately
+                    else {
+
+                        for(int i = node.start; i < node.end; i++) {
+
+                            int index = permutation[i];
+
+                            Vector3 v = points[index];
+
+                            if(v[0] >= min[0]
+                            && v[1] >= min[1]
+                            && v[2] >= min[2]
+
+                            && v[0] <= max[0]
+                            && v[1] <= max[1]
+                            && v[2] <= max[2]) {
+
+                                resultIndices.Add(index);
+                            }
+                        }
+                    }
+
+                }
+            }
+        }
+    }
+
+}