javascript - DOM takes too long to react -


i'm trying "get" image file every 100ms changing source of dom object. can see call indeed returning correct image every 100ms, actual image display updates once second. here's javascript code work:

<img id="videodisplay" style="width:800; height:600"/>  <script type="text/javascript">   function videodatapoll(filename) {     settimeout(function() {       document.getelementbyid("videodisplay").src = filename + "?random="+(new date()).gettime();       videodatapoll(filename);     }, 100);   } </script>

update: changed function use preloading follows:

<canvas id="videodisplay" style="width:800; height:600"/>  <script type="text/javascript">   var x=0, y=0;   var canvas, context, img;   function videodatapoll() {     var filename = getfilename();        canvas = document.getelementbyid("videodisplay");     context = canvas.getcontext("2d");     img = new image();     img.onload = function() {       context.drawimage(img, x, y);       settimeout("videodatapoll()", 100);     }     img.src = filename + "?random=" + (new date()).gettime();   } <script>

still updates @ same speed (which every 5 seconds, not 1s stated originally). every 50 requests (10/sec 5 seconds) element gets updated once.

another important note: second solution works on localhost, run issue when i'm running same webpage off of remote host.

i suggest use onload handler image instead of fixed timeout:

  function videodatapoll(filename) {       document.getelementbyid("videodisplay").src = filename + "?random="+(new date()).gettime();   }    document.getelementbyid("videodisplay").onload = videodatapoll;   videodatapoll(filename);

in case need filename inside function rather passing param.


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