Helen example

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Helen, feel free to send me a msg (marzinp@free.fr) if you need more help.

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Ball []myballs;//global objects array
void setup() {
  size(300, 300);
  myballs=new Ball[4];
  for (int i=0; i<4; i++) {
    myballs[i]=new Ball();//Ball objects instanciation (creation of an object according to the class constructor
  }
}
void draw() {// Processing looping method
  background(255);
  for (Ball myball : myballs) {
    myball.display();
  }
}
void mouseReleased() {//this method is special, it is fired by mouseReleased system event
  for (Ball myball : myballs) {
    myball.reactToMouse();
  }
}

//from here this is my class definition
class Ball {
  float x, y;
  int diameter=20;
  Ball() {//Constructor
    x=random(width);
    y=random(height);
  }
  void display() {//display method
    ellipse(x, y, diameter, diameter);
  }
  void reactToMouse() {//event answer method cannot be triggered directly, it has to be called from the main program mouseReleased() method
    fill(random(255));
    x=random(width);
    y=random(height);
    display();
  }
}