Question

为了自学javascript（以及获取/提供天文学领域的更多见解:)），我正在设置一个页面，显示太阳和月亮的相对位置。现在，太阳和月亮运动的速度仍然是固定的，但我真的想通过输入字段动态地用户定义。因此，初始速度为“30”，用户可以加快速度或降低速度。 显然，太阳和月亮之间的比例必须保持不变。我尝试了很多东西（看到代码中的一些遗物，但我无法让它发挥作用。

有javascript经验的人可以帮我这么做吗？此外，我注意到在此动画期间CPU使用率非常高。是否有简单的步骤使这个脚本更有效？

var dagen = 0;
function speed($this){
	var speedSetting = $this.value;
    //alert(speedSetting);
	//return per;
}
function periode(bolletje, multiplier=30){
	if (bolletje == 'zon'){var per = (multiplier*24/2);}
    if (bolletje == 'maan'){var per = (multiplier*24*29.5/2);}
    return per;
}
function step(delta) {
  elem.style.height = 100*delta + '%'
}
function animate(opts) {
  var start = new Date 
  var id = setInterval(function() {
    var timePassed = new Date - start
    var progress = timePassed / opts.duration
    if (progress > 1) progress = 1
    var delta = opts.delta(progress)
    opts.step(delta)
    if (progress == 1) {
      clearInterval(id)
    }
  }, opts.delay || 10)
   
}
function terugweg(element, delta, duration) {
    var to = -300;
    var bolletje = element.getAttribute('id');
    per = periode(bolletje);
	document.getElementById(bolletje).style.background='transparent';
	animate({
		delay: 0,
		duration: duration || per,
		//1 sec by default
		delta: delta,
		step: function(delta) {
		  element.style.left = ((to*delta)+300) + "px"   
		}
	});
    if(bolletje == 'zon'){
    	dagen ++;
    }
    bolletje = element;
    document.getElementById('dagen').innerHTML = dagen;
    //setInterval(function (element) {
    setTimeout(function (element) {
		move(bolletje, function(p) {return p})
	}, per);
}
function move(element, delta, duration) {
	var to = 300;
	var bolletje = element.getAttribute('id');
    per = periode(bolletje);
    document.getElementById(bolletje).style.background='yellow';
	animate({
		delay: 0,
		duration: duration || per, 
		//1 sec by default
		delta: delta,
		step: function(delta) {
		  element.style.left = to*delta + "px"   
		}
	});
    bolletje = element;
	//setInterval(function (element) {
    setTimeout(function (element) {
		terugweg(bolletje, function(p) {return p})
	}, per);
}

hr{clear: both;}
form{display: block;}
form label{width: 300px; float: left; clear: both;}
form input{float: right;}
.aarde{width: 300px; height: 300px; border-radius: 150px; background: url('https://domain.com/img/aarde.png');}
#zon{width: 40px; height: 40px; background: yellow; border: 2px solid yellow; border-radius: 20px; position: relative; margin-left: -20px; top: 120px;}
#maan{width: 30px; height: 30px; background: yellow; border: 2px solid yellow; border-radius: 16px; position: relative; margin-left: -15px; top: 115px;}

<form>

<div onclick="move(this.children[0], function(p) {return p}), move(this.children[1], function(p) {return p})" class="aarde">
<div id="zon"></div>
<div id="maan"></div>

</div>

Dagen: <span id="dagen">0</span>

</form>


<form>

<label><input id="snelheid" type="range" min="10" max="300" value="30" oninput="speed(this)">Snelheid: <span id="snelheidDisplay">30</span></label>

</form>

Answer 1

首先，在速度输入标记中将onlick更改为oninput。

<input id="snelheid" type="number"  value="30" oninput="speed(this)">

并在speed()功能集multiplier = $this.value中。 multiplier应该是全球性的：

var multiplier = 30;
function speed($this){
  console.log($this.value);
    multiplier = $this.value;
    //alert(speedSetting);
    //return per;
}
function periode(bolletje){
    if (bolletje == 'zon'){var per = (multiplier*24/2);}
    if (bolletje == 'maan'){var per = (multiplier*24*29.5/2);}
    return per;
}

这是一个例子： https://jsfiddle.net/do4n9L03/2/

注意：multiplier不是速度，而是延迟。如果你增加它会变慢

动态更改动画速度

1 个答案: