/// Generates pseudo random double
/// based on input [Vector2], try to
/// change numbers within to see how it changes
/// the pattern generated. Try some small integers
/// to see more repetition in how tiles are placed.
double random2(Vector2 vec) {
  // return vec.x % 2 + vec.y % 2;
  // return frac(vec.dot(vec.xy) * 0.28);
  // return frac(vec.x * vec.y * .99);

  return frac(
    sin(vec.dot(Vector2(11.12312312, 21.31231231))) * 43243.42987234,
  );
}

/// Main area of interest, this function will
/// return color for each particular color on our [ui.Image]
int generatePixel(int x, int y, Size size) {
  var tiles = 25.0;
  var uv = Vector2(x / size.width, y / size.height);
  uv.y /= size.aspectRatio;

  // This is our x,y from 0 to tiles
  var tileCoordinate = uv * tiles;

  // This vector would only have unique values
  // within each cell. Essentially,
  // it's an integer coordinate of the cell.
  // Vector2(0.1, 4.4) -> Vector2(0.0, 4.0);
  var tileIndex = tileCoordinate.clone()..floor();

  // Compute uv position within given tile
  // Vector2(0.1, 4.4) -> Vector2(0.1, 0.4);
  var gridUv = frac2(tileCoordinate);

  // 50-50% chance of generating either of two
  // tile fillings.
  // First is light vertical stripes, second
  // is slightly darker horizontal ones
  if (random2(tileIndex) > .5) {
    return (gridUv.x < .5)
      ? 0xffeeeeee
      : 0xff000000;
  } else {
    return gridUv.y < .5
      ? 0xff000000
      : 0xff999999;
  }
}