Processing – Rebondir

float balleX;
float balleCote;
float dirX = 5;

void setup(){
  size(800, 600);
  
  balleCote = 10;
  balleX = width / 2;
}

void draw(){
  background(0);
  
  // Validation de la direction
  if (balleX + balleCote > width) {
    dirX = -1 * dirX;
  }
  // Validation de la direction
  if (balleX < 0) {
    dirX = -1 * dirX;
  }
  
  // Change la direction
  balleX = balleX + dirX;
  
  // Dessin
  rect (balleX, height / 2, balleCote, balleCote);
  
}