矩形与碰撞点关系

一定碰撞，碰撞点在矩形内

const cube2: egret.Shape = new egret.Shape();
cube2.graphics.beginFill(0x000000);
cube2.graphics.drawRect(0, 0, 31, 41);
cube2.graphics.endFill();
this.addChild(cube2);
console.log('方矩形与碰撞点：', cube2.hitTestPoint(30, 40, true)); // true
console.log('包围盒与碰撞点：', cube2.hitTestPoint(30, 40)); // true

一定不碰撞，碰撞点在矩形外

const cube3: egret.Shape = new egret.Shape();
cube3.graphics.beginFill(0x000000);
cube3.graphics.drawRect(0, 0, 29, 39);
cube3.graphics.endFill();
this.addChild(cube3);
console.log('方矩形与碰撞点：', cube3.hitTestPoint(30, 40, true)); // false
console.log('包围盒与碰撞点：', cube3.hitTestPoint(30, 40)); // false

临界点，包围盒碰撞，矩形本身不碰撞

const cube1: egret.Shape = new egret.Shape();
cube1.graphics.beginFill(0x000000);
cube1.graphics.drawRect(0, 0, 300, 400);
cube1.graphics.endFill();
this.addChild(cube1);
console.log('方矩形与碰撞点：', cube1.hitTestPoint(300, 400, true)); // false 
console.log('包围盒与碰撞点：', cube1.hitTestPoint(300, 400)); // true

圆与碰撞点关系

一定碰撞，碰撞点在圆内，临界值

• 碰撞点在圆内

const circle3: egret.Shape = new egret.Shape();
circle3.graphics.beginFill(0x000000);
circle3.graphics.drawCircle(0, 0, 51);
circle3.graphics.endFill();
this.addChild(circle3);
console.log('正圆形与碰撞点：', circle3.hitTestPoint(30, 40, true)); // true
console.log('包围盒与碰撞点：', circle3.hitTestPoint(30, 40)); // true

• 临界值

const circle1: egret.Shape = new egret.Shape();
circle1.graphics.beginFill(0x000000);
circle1.graphics.drawCircle(0, 0, 50);
circle1.graphics.endFill();
this.addChild(circle1);
console.log('正圆形与碰撞点：', circle1.hitTestPoint(30, 40, true)); // true
console.log('包围盒与碰撞点：', circle1.hitTestPoint(30, 40)); // true

包围盒碰撞，圆本身与碰撞点不碰撞

const circle2: egret.Shape = new egret.Shape();
circle2.graphics.beginFill(0x000000);
circle2.graphics.drawCircle(0, 0, 49);
circle2.graphics.endFill();
this.addChild(circle2);
console.log('正圆形与碰撞点：', circle2.hitTestPoint(30, 40, true)); // false
console.log('包围盒与碰撞点：', circle2.hitTestPoint(30, 40)); // true

矩形碰撞与圆形碰撞检测区别

矩形碰撞检测，是判断显示对象的包围盒是否与一点相交；
像素碰撞检测，是判断显示对象的图案（非透明区域）是否与一点相交。

注意

• 大量使用像素碰撞检测，会消耗更多的性能