excited

int frames=240, num=16;
float theta, rotAngle;

void setup() {
  size(540, 540);
  noFill();
  stroke(255);
}

void draw() {
  background(0);
  float t = (frameCount%frames)/float(frames);
  rotAngle = map(t, 0, 1, 0, TWO_PI*3)* ease(t, 1, 3);
  for (int i=0; i<num; i++) {
    pushMatrix();
    translate(width/2,height/2);
    rotate(TWO_PI/num*i);
    float x = map(sin(theta+rotAngle),-1,1,30,200);
    ellipse(x,0,30,30);
    popMatrix();
  }
  theta += TWO_PI/frames;
}

float ease(float t, float e) {
  return t < 0.5 ? 0.5 * pow(2*t, e) : 1 - 0.5 * pow(2*(1 - t), e);
}

float ease(float t, float in, float out) {
  return (1-t)*ease(t, in) + t*ease(t, out);
}