!7

p { pMain(HeartBeat); }

public sclass HeartBeat extends PApplet {

  public void settings() { size(600, 200); }

  int x = 0;

  float py = 0;

  public void setup() {

    background(0);

  }

  public void draw() {

    noStroke();

    fill(0,0,0,15);

    rect(0,0,width,height);

    translate(0,height/2);

    x++;

    x%=width;

    float fx = py + random(-20,20);

    stroke(100,255,100);

    noFill();

    line(x-1,py, x,fx);

    py = fx;

    if(py>height/2) py=height/2;

    if(py<-height/2) py=-height/2;

  }

}