Preparation code

<canvas id="screen"></canvas>
<script>
  var ctx = document.getElementById("screen").getContext("2d");
  var image = document.createElement("img");
  image.src = "http://icons.iconarchive.com/icons/ph03nyx/super-mario/48/Retro-Mushroom-1UP-2-icon.png";
  
  function fasterRound(value)
  {
    return(~~(value+(value > 0 ? .5 : -.5)));
  }
  
  function fasterRoundPos(value)
  {
    return(~~(value+0.5));
  }
  function nop(value) { return(value); }
</script>

Preparation code output

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ctx.drawImage(image, Math.round(0.5), Math.round(0.5));

ctx.drawImage(image, 0.5, 0.5);

ctx.drawImage(image, fasterRound(0.5), fasterRound(0.5));

ctx.drawImage(image, 0, 0);

ctx.drawImage(image, fasterRoundPos(0.5), fasterRoundPos(0.5));

ctx.drawImage(image, nop(0), nop(0));

ctx.drawImage(image, ~~(0.5+0.5), ~~(0.5+0.5));

ctx.drawImage(image, nop(0.5), nop(0.5));

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Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL. Here’s a list of current revisions for this page:

• Revision 1: published on 12th December 2010
• Revision 7: published on 5th July 2011
• Revision 8: published on 3rd September 2011
• Revision 9: published on 14th September 2011
• Revision 10: published by skyblue on 21st March 2012
• Revision 12: published on 26th June 2012
• Revision 13: published on 2nd October 2012
• Revision 14: published by ryan jacobson on 23rd October 2012
• Revision 16: published on 15th February 2013
• Revision 17: published 3 weeks ago

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