html5 canvas流星陨石掉落地面爆炸动画特效

代码片段：

this.update = 函数(i) {
this.rotation = this.velocity.rotate * this.timescale;
this.position.x =
Math.cos(this.velocity.phi) * this.velocity.length * this.timescale;
this.position.y =
Math.sin(this.velocity.phi) * this.velocity.length * this.timescale;
this.position.x =
Math.cos(this.gravity.phi) * this.gravity.length * this.timescale;
this.position.y =
Math.sin(this.gravity.phi) * this.gravity.length * this.timescale;
this.velocity.phi = this.accelerate.phi.change * this.timescale;
(this.velocity.phi > this.accelerate.phi.max ||
this.velocity.phi < this.accelerate.phi.min) &&
(this.accelerate.phi.change = -this.accelerate.phi.change);
this.velocity.length *= this.accelerate.friction;
if (this.position.y > this.ground) {
var ctx = this.vfx;
var 位置 = this.position;
var range = this.edge;
var main = this.main;
[...新数组(this.edge)].map(
() =>
main.makeRock({
位置: { x: 位置.x, y: 位置.y },
基数：范围
}) ||
光耀(
ctx，
position.x Math.random() * 10 * 范围 - 5 * 范围,
position.y Math.random() * 6 * 范围 - 3 * 范围,
范围 * Math.random() * 30 30
)
);
this.main.meteors.splice(i, 1);
this.main.makeMeteor();
}
};