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<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <title>yoob.Chargen Demo</title>
  <style>
#canvas {
  border: 1px solid blue;
  width: 640px;
  height: 400px;
}
  </style>
</head>
<body>

<h1>yoob.Chargen Demo</h1>

<canvas id="canvas" width="320" height="200">
Your browser doesn't support displaying an HTML5 canvas.
</canvas>

<button onclick="reprogram();">Reprogram Character</button>

</body>
<script src="../src/yoob/chargen.js"></script>
<script>
  var chargen = new yoob.Chargen();
  var triples = [
      [0, 0, 0],
      [0, 0, 255],
      [0, 255, 0],
      [0, 255, 255],
      [255, 0, 0],
      [255, 0, 255],
      [255, 255, 0],
      [255, 255, 255]
  ];
  var tripleToCss = function(triple) {
      return "rgb(" + triple[0] + "," + triple[1] + "," + triple[2] + ")";
  };
  var draw = function() {
      var canvas = document.getElementById('canvas');
      var ctx = canvas.getContext('2d');
      ctx.clearRect(0, 0, canvas.width, canvas.height);
      for (var x = 0; x < 40; x++) {
          for (var y = 0; y < 25; y++) {
              var bgColour = y % 8;
              ctx.fillStyle = tripleToCss(triples[bgColour]);
              ctx.fillRect(x * 8, y * 8, 8, 8);
              var charNum = (y * 40 + x) % 17;
              if (charNum === 16) charNum = 0;
              var charColour = (y * 40 + x) % 8;
              chargen.blitChar(charNum, charColour, ctx, x * 8, y * 8);
          }
      }
  };
  chargen.init(triples, 8, 8, 8, 2, "charset8.png", draw);
  function reprogram() {
      var data = [];
      for (var i = 0; i < 8; i++) {
          data.push(Math.floor(Math.random() * 256));
      }
      chargen.modifyChar(15, data);
      draw();
  };
</script>