Generate and draw a fractal tree.

 Draw the trunk
 At the end of the trunk, split by some angle and draw two branches
 Repeat at the end of each branch until a sufficient level of branching is reached


Related tasks
 Pythagoras Tree


<html>
<body>
<canvas id="canvas" width="600" height="500"></canvas>
 
<script type="text/javascript">
var elem = document.getElementById('canvas');
var context = elem.getContext('2d');
 
context.fillStyle = '#C0C0C0';
context.lineWidth = 1;
 
var deg_to_rad = Math.PI / 180.0;
var depth = 9;
 
function drawLine(x1, y1, x2, y2, brightness){
  context.moveTo(x1, y1);
  context.lineTo(x2, y2);
}
 
function drawTree(x1, y1, angle, depth){
  if (depth !== 0){
    var x2 = x1 + (Math.cos(angle * deg_to_rad) * depth * 10.0);
    var y2 = y1 + (Math.sin(angle * deg_to_rad) * depth * 10.0);
    drawLine(x1, y1, x2, y2, depth);
    drawTree(x2, y2, angle - 20, depth - 1);
    drawTree(x2, y2, angle + 20, depth - 1);
  }
}
 
context.beginPath();
drawTree(300, 500, -90, depth);
context.closePath();
context.stroke();
</script>
 
</body>
</html>