Loop arrayList Crossyroad

Processing Beginners
4

Sounds like you are having trouble making cars go off one end of the screen and then appear at the other end of the screen. A neat trick to deal with this is to just draw each car twice, and correct the position of any car that has gone past the edge.

Example:

class Foo {
  float px, py, vx;
  color c;
  Foo(float ipy) {
    px = random(width);
    vx = random(0.5,10);
    py = ipy;
    c = color(random(255), random(255), random(255));
  }
  void draw() {
    px+=vx;
    px%=width;
    fill(c);
    rect(px, py, 20, 20);
    rect(px-width, py, 20, 20);
  }
}

ArrayList<Foo> foos = new ArrayList();

void setup() {
  size(600, 600);
  for (int i=0; i<30; foos.add(new Foo((i++)*20)));
}

void draw() {
  background(0);
  for (int i=0; i<30; foos.get(i++).draw());
}