function insertStrokedArc(batch, x1, y1, radius, color) {
  let x2 = radius;
  let y2 = 0;
  let err = 0;
  const size = SETTINGS.PENCIL_SIZE;
  for (;x2 >= y2;) {
    batch.drawAt(x2 + x1, y2 + y1, size, color);
    batch.drawAt(y2 + x1, x2 + y1, size, color);
    batch.drawAt(-x2 + x1, y2 + y1, size, color);
    batch.drawAt(-y2 + x1, x2 + y1, size, color);
    batch.drawAt(-x2 + x1, -y2 + y1, size, color);
    batch.drawAt(-y2 + x1, -x2 + y1, size, color);
    batch.drawAt(x2 + x1, -y2 + y1, size, color);
    batch.drawAt(y2 + x1, -x2 + y1, size, color);
    if (err <= 0) {
      y2 += 1;
      err += 2 * y2 + 1;
    }
    if (err > 0) {
      x2 -= 1;
      err -= 2 * x2 + 1;
    }
  };
}
Inserts filled arc at given position
@param {Batch} batch
@param {Number} x1
@param {Number} y1
@param {Number} radius
@param {Array} color