dct-hydra.js

//https://refactorman.com/2015/04/28/exploring-the-dct-part-i/
var dct = function (input) {
	var output = [], v, u, x, y, sum, val, au, av;
	for (v = 0; v < 8; v++) {
    output.push([])
		for (u = 0; u < 8; u++) {
			sum = 0;
			for (y = 0; y < 8; y++) {
				for (x = 0; x < 8; x++) {
					val = input[y][x];
					val *= Math.cos(((2 * x + 1) * u * Math.PI) / 16);
					val *= Math.cos(((2 * y + 1) * v * Math.PI) / 16);
					sum += val;
				}
			}
			au = u === 0 ? 1 / Math.SQRT2 : 1;
			av = v === 0 ? 1 / Math.SQRT2 : 1;
			output[v][u] = 1 / 4 * au * av * sum;
		}
	}
	return output;
}

// let v = randomVector(8*8)
let v = []

for(let i = 0; i < 8; i++) {
  let u=[]
  for(let j = 0; j < 8; j++) {
    // if (i < 4)
    // if (i < 4&&j<4)
    // u.push(1)
    // else
    // u.push(0)
    u.push(Math.max(0, 1-Math.sqrt((i-3.5)*(i-3.5) + (j-3.5)*(j-3.5))))
  }
  v.push(u)
}

console.log(v)
let o = dct(v)
let code = "solid()"
for(let i = 0; i < o.length; i++) {
  for(let j = 0; j < o[i].length; j++) {
    if(Math.abs(o[i][j]) < 1e-9) {
      o[i][j] = 0
    }
    else {
      let au,av,val
      au = i === 0 ? 1/Math.SQRT2 : 1;
      av = j === 0 ? 1/Math.SQRT2 : 1;
      val = o[i][j];
      val *= au;
      val *= av;
      // let c = `osc(Math.PI*2*${i},0,-Math.PI/2*${i/32}).brightness(-.5).color(2,2,2).r().rotate(Math.PI/2).mult(osc(Math.PI*2*${j},0,-Math.PI/2*${j/32}).brightness(-.5).color(2,2,2).r()).color(${val},${val},${val})`;
      let y = `osc(Math.PI*${i*2},0,-Math.PI/2-Math.PI*${i/16}).brightness(-.5).color(2).rotate(Math.PI/2)`
      let x = `osc(Math.PI*${j*2},0,-Math.PI/2-Math.PI*${j/16}).brightness(-.5).color(2)`
      let c = `${y}.mult(${x}).color(${val})`;
      if (i == 0) c = `${x}.color(${val})`
      else if (j == 0) c = `${y}.color(${val})`
      // console.log(i, j, val, c)
      code = `${code}.add(${c})`
      // val *= Math.cos(((2*x+1) * u * Math.PI)/16);
      // val *= Math.cos(((2*y+1) * v * Math.PI)/16);
    }
  }
}
console.log(code + ".color(1/8).r().modulate(solid(1,1),-.25).out()")
//console.log(o)