let angle = 0;
let w = 40;
let ma;
let maxD;

function setup() {
   createCanvas(600, 600, WEBGL);
   ma = atan(1 / sqrt(2))
   maxD = dist(0, 0, 200, 200);
}

function draw() {
   background(220);
   ortho(-700, 700, 700, -700, 0, 1200);

   rotateX(-ma);
   rotateY(QUARTER_PI);

   rectMode(CENTER);

   let offset = 0;
   for (let z = 0; z < height; z += w) {
      for (let x = 0; x < width; x += w) {
         push();
         let d = dist(x, z, width / 2,height / 2);
         let offset = map(d, 0, maxD, -PI, PI);
         let a = angle + offset;
         let h = floor(map(sin(a), -1, 1, 120, 320));
         translate(x - width / 2, 0, z - height / 2);
         normalMaterial();
         box(w - 2, h, w - 2);
         pop();
      }
      offset += 0.1;
   }

   angle -= 0.08;
}