Track mouse speed with JS

Question

What's the best way to track the mouse speed with plain JS/JQuery? I'd like to track how fast a user moves the mouse in all directions (up/down/left/right).

Answer 1

Sparklines has a nifty example of tracking mouse movement and graphing it. Their code is available in the source of their site starting at line 315.

Simple and effective.

Here is the code:

 var mrefreshinterval = 500; // update display every 500ms  var lastmousex=-1;   var lastmousey=-1;  var lastmousetime;  var mousetravel = 0;  $('html').mousemove(function(e) {      var mousex = e.pageX;      var mousey = e.pageY;      if (lastmousex > -1)          mousetravel += Math.max( Math.abs(mousex-lastmousex), Math.abs(mousey-lastmousey) );      lastmousex = mousex;      lastmousey = mousey;  });