鼠标移动时页面背景渐变变化

Question

I have a page with a gradient applied on page load via CSS and would like to animate the page alternating the gradient colors and degree (linear-gradient - 4 different colors all degrade to white) on mouse move. If I use only 2 colors it works fine. But I want to get a random color from an array on mouse move but it flickers. Any solution for that?

Here's my Fiddle

var colorArr = ['#dfa7ca', '#f7c2b3', '#bae0f1', '#a6d6cb'];
var grFrom = colorArr[Math.floor(Math.random()*colorArr.length)];
var grTo = '#FFFFFF';

$("body").mousemove(function( e ) {
  var x = e.pageX - this.offsetLeft;
  var y = e.pageY - this.offsetTop;
  var grFrom = colorArr[Math.floor(Math.random()*colorArr.length)];//get a new random color
  var xy = (x + y) / 8;
  var w = $(this).width(),
  pct = 360*(+e.pageX)/w,
  bg = "linear-gradient(" + xy + "deg,"+grFrom+","+grTo+")";
  $("body").css("background-image", bg);
});

Answer 1

I think you need to inlcude jQueryUI and then you can use animate() to change the color. Please check here:

https://jqueryui.com/animate/

So you should use something like this:

 $( "#selector" ).animate({
          backgroundColor: bg
        }, 10 );

Answer 2

You can wrap your handler in _.throttle , and play with the millis, until you have an acceptable result.

var colorArr = ['#dfa7ca', '#f7c2b3', '#bae0f1', '#a6d6cb'];
var grFrom = colorArr[Math.floor(Math.random()*colorArr.length)];
var grTo = '#FFFFFF';


var wrapped = _.throttle(function(e){
  var x = e.pageX - this.offsetLeft;
  var y = e.pageY - this.offsetTop;
  var grFrom = colorArr[Math.floor(Math.random()*colorArr.length)];
  var xy = (x + y) / 8;
  var w = $(this).width(),
  pct = 360*(+e.pageX)/w,
  bg = "linear-gradient(" + xy + "deg,"+grFrom+","+grTo+")";
  $("body").css("background-image", bg);
},50)//Try increasing/decreasing this value to see the differrence


$("body").mousemove(wrapped);

See: https://jsfiddle.net/g137be71/24/

Update: Actually I had pasted a wrong link. This is for throttle . https://jsfiddle.net/g137be71/82/