Question

我正在使用此功能为我的粒子系统创建一个粒子：

function particle()
{
    this.speed = {x: -1.5+Math.random()*3, y: -12+Math.random()*12};
    this.location = {x: 50, y: 150};
    this.radius = 5+Math.random()*8;
    this.life = 4+Math.random()*8;
    this.remaining_life = this.life;
    this.r = 255;
    this.g = 140;
    this.b = 30;
}

我正在使用此功能在动画过程中更新粒子特征：

particle.prototype.updateparticle = function()
{
    this.remaining_life--;
    this.radius--;
    this.location.x += this.speed.x;
    this.location.y += this.speed.y;

    if(this.remaining_life < 0 || this.radius < 0)
    {
        this.speed = {x: -1.5+Math.random()*3, y: -12+Math.random()*12};
        this.location = {x: 50, y: 150};
        this.radius = 5+Math.random()*8;
        this.life = 4+Math.random()*8;
        this.remaining_life = this.life;
        this.r = 255;
        this.g = 140;
        this.b = 30;    
    }
}

有没有办法可以避免冗余代码？

此外，我尝试使用this = new particle()，但它无效。我想不出它为什么不起作用的原因。为什么不呢？

在一个完全不相关的说明中，Firefox无法处理粒子动画吗？ Chrome使用了我CPU的5％。 Firefox使用大约30个而且仍然滞后！我有一个i5 2500k所以这应该不是问题。我正在运行两者的最新版本。

Answer 1

Apply函数，将当前对象作为this参数传递：

particle.prototype.updateparticle = function()
{
    this.remaining_life--;
    this.radius--;
    this.location.x += this.speed.x;
    this.location.y += this.speed.y;

    if(this.remaining_life < 0 || this.radius < 0)
    {
        particle.apply(this);
    }
}

Answer 2

创建原型函数以初始化值

function particle() {
    this.init();
}

particle.prototype.init = function(){
    this.speed = {x: -1.5+Math.random()*3, y: -12+Math.random()*12};
    this.location = {x: 50, y: 150};
    this.radius = 5+Math.random()*8;
    this.life = 4+Math.random()*8;
    this.remaining_life = this.life;
    this.r = 255;
    this.g = 140;
    this.b = 30;
}

particle.prototype.updateparticle = function() {
    this.remaining_life--;
    this.radius--;
    this.location.x += this.speed.x;
    this.location.y += this.speed.y;

    if(this.remaining_life < 0 || this.radius < 0) {
        this.init();  
    }
}

Answer 3

您可以将其设为另一个功能，并在需要时调用。

function particle()
{
    this.initialize();
}

particle.prototype.initialize = function(){
    this.speed = {x: -1.5+Math.random()*3, y: -12+Math.random()*12};
    this.location = {x: 50, y: 150};
    this.radius = 5+Math.random()*8;
    this.life = 4+Math.random()*8;
    this.remaining_life = this.life;
    this.r = 255;
    this.g = 140;
    this.b = 30;    
}

particle.prototype.updateparticle = function()
{
    this.remaining_life--;
    this.radius--;
    this.location.x += this.speed.x;
    this.location.y += this.speed.y;

    if(this.remaining_life < 0 || this.radius < 0)
    {
        this.initialize();
    }
}

Answer 4

function particle(x, y, r, g, b) {
  this.location = {x: x, y: y};
  this.r = r;
  this.g = g;
  this.b = b;

  // Group everything that randomises in update()
  this.update = function() {
    this.speed = {x: -1.5+Math.random()*3, y: -12+Math.random()*12};
    this.radius = 5+Math.random()*8;
    this.life = 4+Math.random()*8;
    this.remaining_life = this.life;
  }

  this.update();
}


particle.prototype.updateparticle = function() {
  this.remaining_life--;
  this.radius--;
  this.location.x += this.speed.x;
  this.location.y += this.speed.y;

  if(this.remaining_life < 0 || this.radius < 0) {
    this.update();
  }
}

//Instantiation
var p1 = new particle(50, 150, 255, 140, 30);

使用javascript构造函数重新初始化现有对象

4 个答案: