trippy dots

gridCube.pde

void setup() {
  size(720, 720, P3D);
  smooth(8);
  noStroke();
  fill(200);
  ortho(-width/2, width/2, -height/2, height/2, -width/2, 3*width);
}

int N = 16, n = 5, l = 50, r = 2; //"n" is side length of the inner cube
float t, ang = PI/100;
void draw() {
  t = mouseX*1.0/width;

  background(30);
  push();
  translate(width/2, height/2);
  rotateY(sin(TWO_PI*t)*ang);
  rotateX((cos(TWO_PI*t)-1)*ang); 
  for (int a = 0; a < 3; a++) {
    push();
    rotate(TWO_PI/3*a);
    rotateX(-atan(1/sqrt(2)));
    for (int i = 0; i < N; i++) {
      for (int j = 0; j < N; j++) {
        push();
        if (i + 1 > n || j + 1 > n) {
          rotateY(-PI/4);
          translate(i*l, -j*l);
          sphere(r);
        } else {
          rotateY(PI/4);
          translate(i*l - (n - 1)*l, -j*l, (n - 1)*l);
          sphere(r);
        } 
        pop();
      }
    }
    pop();
  }
  pop();
}

void push() {
  pushMatrix();
  pushStyle();
}

void pop() {
  popStyle();
  popMatrix();
}