the demo

assets/Scripts/common/QuadTree.ts

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+import { Rect, _decorator } from "cc";
+const { ccclass } = _decorator;
+
+@ccclass("QuadTree")
+export default class QuadTree {
+
+    nodes = [];
+    objects = [];  //該容器的物體集合
+    max_levels: number;  // 最大深度
+    max_objects: number;  // 該容器最大容量
+    level: number;   //當前深度
+    bounds: Rect = null; // 容器範圍(Rect)
+
+    constructor(boundary, level) {
+        this.max_objects = 4;
+        this.max_levels = 4;
+
+        this.level = level || 0;
+        this.bounds = boundary;
+
+        this.objects = [];
+        this.nodes = [];
+    }
+
+    insert(pRect) {
+        var i = 0, indexes;
+
+        //if we have subnodes, call insert on matching subnodes
+        if (this.nodes.length) {
+            indexes = this.getIndex(pRect);
+
+            for (i = 0; i < indexes.length; i++) {
+                this.nodes[indexes[i]].insert(pRect);
+            }
+            return;
+        }
+
+        //otherwise, store object here
+        this.objects.push(pRect);
+
+        //max_objects reached
+        if (this.objects.length > this.max_objects && this.level < this.max_levels) {
+
+            //split if we don't already have subnodes
+            if (!this.nodes.length) {
+                this.split();
+            }
+
+            //add all objects to their corresponding subnode
+            for (i = 0; i < this.objects.length; i++) {
+                indexes = this.getIndex(this.objects[i]);
+                for (var k = 0; k < indexes.length; k++) {
+                    this.nodes[indexes[k]].insert(this.objects[i]);
+                }
+            }
+
+            //clean up this node
+            this.objects = [];
+        }
+    }
+
+    split() {
+        var nextLevel = this.level + 1,
+            subWidth = this.bounds.width / 2,
+            subHeight = this.bounds.height / 2,
+            x = this.bounds.x,
+            y = this.bounds.y;
+
+        //top right node
+        this.nodes[0] = new QuadTree({
+            x: x + subWidth,
+            y: y,
+            width: subWidth,
+            height: subHeight
+        }, nextLevel);
+
+        //top left node
+        this.nodes[1] = new QuadTree({
+            x: x,
+            y: y,
+            width: subWidth,
+            height: subHeight
+        }, nextLevel);
+
+        //bottom left node
+        this.nodes[2] = new QuadTree({
+            x: x,
+            y: y + subHeight,
+            width: subWidth,
+            height: subHeight
+        }, nextLevel);
+
+        //bottom right node
+        this.nodes[3] = new QuadTree({
+            x: x + subWidth,
+            y: y + subHeight,
+            width: subWidth,
+            height: subHeight
+        }, nextLevel);
+    }
+
+
+    getIndex(pRect) {
+        var indexes = [],
+            verticalMidpoint = this.bounds.x + (this.bounds.width / 2),
+            horizontalMidpoint = this.bounds.y + (this.bounds.height / 2);
+
+        var startIsNorth = pRect.y < horizontalMidpoint,
+            startIsWest = pRect.x < verticalMidpoint,
+            endIsEast = pRect.x + pRect.width > verticalMidpoint,
+            endIsSouth = pRect.y + pRect.height > horizontalMidpoint;
+
+        //top-right quad
+        if (startIsNorth && endIsEast) {
+            indexes.push(0);
+        }
+
+        //top-left quad
+        if (startIsWest && startIsNorth) {
+            indexes.push(1);
+        }
+
+        //bottom-left quad
+        if (startIsWest && endIsSouth) {
+            indexes.push(2);
+        }
+
+        //bottom-right quad
+        if (endIsEast && endIsSouth) {
+            indexes.push(3);
+        }
+
+        return indexes;
+    }
+
+
+    retrieve(pRect) {
+        var indexes = this.getIndex(pRect),
+            returnObjects = this.objects;
+
+        //if we have subnodes, retrieve their objects
+        if (this.nodes.length) {
+            for (var i = 0; i < indexes.length; i++) {
+                returnObjects = returnObjects.concat(this.nodes[indexes[i]].retrieve(pRect));
+            }
+        }
+
+        //remove duplicates
+        returnObjects = returnObjects.filter(function (item, index) {
+            return returnObjects.indexOf(item) >= index;
+        });
+
+        return returnObjects;
+    }
+
+    objLen() {
+
+        if (this.nodes.length > 0) {
+            let len = 0;
+            for (let node of this.nodes) {
+                len += node.objLen();
+            }
+            return len;
+        } else {
+            //console.log('this.objects.length------',this.objects.length)
+            return this.objects.length;
+        }
+    }
+
+}

assets/Scripts/common/QuadTree.ts.meta

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+{
+  "ver": "4.0.23",
+  "importer": "typescript",
+  "imported": true,
+  "uuid": "469a12f5-f4ff-4458-94aa-0a440aaa114b",
+  "files": [],
+  "subMetas": {},
+  "userData": {}
+}