//still working
float left=50, right=350, top=50, bottom=250;
float ballX, ballY, ballDX, ballDY;
float mX, mY;
void draw () {
  //next frame
  scence ();
  msgs();
  action();
}
void setup () {
 (500,500);
}
void reset () {
  ballX=ballX + ball DX
void action (){
  my ball()  
  if (ballX > ball right \\ ballX< ball left) ballDX=ballDX; 
}