void keyPressed(){
  switch(keyCode){
    case UP: up =        true; break;
    case DOWN : down =   true; break;
    case LEFT : left =   true; break;
    case RIGHT : right = true; break;
    case 90: z=         true; break;//z
    case 81: q=         true; break;//q
    case 83: s=         true; break;//s
    case 68: d=         true; break;//d

  }

}
void keyReleased(){
   switch(keyCode){
    case UP: up =        false; break;
    case DOWN : down =   false; break;
    case LEFT : left =   false; break;
    case RIGHT : right = false; break;
     case 90: z=         false; break;//z
    case 81: q=          false; break;//q
    case 83: s=          false; break;//s
    case 68: d=          false; break;//d
  }
}