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HTML

Posted by Björn Norén
Björn Norén
9,569 Points

Canvas | Move box animation

Hello there! I have this code there a blue square is moving from the left corner to the right, but it occurs instantly and I'm trying to figure out how to slow down the speed, is there anyone who knows? And could you show me how to solve it?

I have tried setTimeout(); and setInterval();, but I'm failing at using the correct

 <!DOCTYPE html>
<html>
<head>
<style type="text/css">
    body {
        margin: 40px; background:#666;
    }
    #my_canvas {
        background:#fff; border:#000 1px solid;
    }
</style>
<script>
    function draw(){
        var canvas = document.getElementById("my_canvas");
        var ctx = canvas.getContext("2d");
        var x = 0;

        for (var i = 0; i < 500; i++){
           ctx.fillStyle = 'blue';
           ctx.fillRect(x, 0, 100, 100);
           x++;
        }
    }

window.onload = draw;

</script>
</head>
<body>
<canvas id="my_canvas" width="500" height="500">
</canvas>
</body>
</html>

1 Answer

Steven Parker
Steven Parker
243,318 Points
Steven Parker
Steven Parker
243,318 Points

Here's an example using setInterval:

function draw() {
  var canvas = document.getElementById("my_canvas");
  var ctx = canvas.getContext("2d");
  var x = 0;

  function moveBox() {
    ctx.fillStyle = 'blue';
    ctx.fillRect(x, 0, 100, 100);
    ctx.fillStyle = 'white';    // move not stretch
    ctx.fillRect(x - 1, 0, 1, 100);
    if (++x > 400)
      clearInterval(iv);
  }

  var iv = setInterval(moveBox, 10);
}

window.onload = draw;
Björn Norén
Björn Norén
9,569 Points

Suuuuuper huge thanks!