docs: function arcToBeziers(angleStart, angleExtent) {
     var numSegments = Math.ceil(Math.abs(angleExtent) / 90.0);
  
     var angleIncrement = (angleExtent / numSegments);
  
    // The length of each control point vector is given by the following formula.
    var controlLength = 4.0 / 3.0 * Math.sin(angleIncrement / 2.0) / (1.0 + Math.cos(angleIncrement / 2.0));
  
    var commands = [];
  
    for (var i = 0; i < numSegments; i++) {
        var cmd = { command: 'curveTo', code: 'C' };
        var angle = angleStart + i * angleIncrement;
        // Calculate the control vector at this angle
        var dx = Math.cos(angle);
        var dy = Math.sin(angle);
        // First control point
        cmd.x1 = (dx - controlLength * dy);
        cmd.y1 = (dy + controlLength * dx);
        // Second control point
        angle += angleIncrement;
        dx = Math.cos(angle);
        dy = Math.sin(angle);
        cmd.x2 = (dx + controlLength * dy);
        cmd.y2 = (dy - controlLength * dx);
        // Endpoint of bezier
        cmd.x = dx;
        cmd.y = dy;
        commands.push(cmd);
    }
    return commands;
  }