class MyObject{
  float dim = 40; //size of the object
  float x,y,z; //position coordinates
  boolean picked = false; //picked status
  color c_face = color(255); //color of object//determine whether an object is picked
  void pick(float xp, float yp){
    //is the distance enough to pick?
    if(dist(xp,yp,screenX(x,y,z),screenY(x,y,z))<dim)
      picked = true;
    else
      picked = false;
  }
  void draw3(){
    if(picked==true)
      fill(255,0,0); //paint red to indicate picked
    else
      fill(c_face); //normal color
    box(dim);
  }
}