int x=0;
int y=100;
int i=0;
int r = 1;
float r1 =0;
float r2 = 0;

void setup() {
  size(400,400);
  background(200,0,0);
  ellipseMode(CENTER_DIAMETER);
  rectMode(CENTER_DIAMETER);
}

void loop() {
  background(200,0,0);
  noStroke();
  

    elli(i,i,50,50); //(i*2)%400 mod
    stroke(255,255,255);
    lin1(10,20,100,120+i);
    i=i+(5*r);
    
   if (i == 400)  r = -1;
    if (i== -5) r = 1;

 
       
}

void elli(float x, float y, float rad, float rad2){

ellipse(x,y,rad,rad2);
}
void lin1(float a, float b, float c, float d){

line(a,b,c,d);
line(b,c,d,a);
line(d,c,a,b);
line(a,d,b,c);
}