[rbdr/tomato-sauce] / lib / screens / circle.js

'use strict';

/**
 * Draws concentric circles. Each ring has its own color.
 *
 * @function CircleScreen
 * @implements IScreen
 */
module.exports = function (modulation, width, height, renderer) {

  let response = [];

  const circles = width > height ? height : width;

  for (let i = 0; i < circles; ++i) {
    const centerX = Math.round(width / 2) + 1;
    const centerY = Math.round(height / 2) + 1;

    const red = Math.floor(Math.random() * 255);
    const blue = Math.floor(Math.random() * 255);
    const green = Math.floor(Math.random() * 255);

    for (let j = 0; j < 180; ++j) {
      const angle =  2 * j * (Math.PI / 180);
      const x = Math.round(centerX + Math.sin(angle) * i);
      const y = Math.round(centerY + Math.cos(angle) * i);

      if (x <= width && x > 0 && y <= height && y > 0) {
        const position = `\x1B[${y};${x}H`; // Move cursor to y,x (CSI y;x H)
        response += `${position}${renderer(red, blue, green)} `;
      }
    }
  }

  return response;
};