2番目の画面内でクラスを使うときの注意

UsingClassInSecondWindow.pde

SecondWindow secondWindow;

void settings() {
  size(200, 200);
}

void setup() {
  secondWindow = new SecondWindow();
}

void draw() {
  background(255, 0, 0);
}

class SecondWindow extends PApplet { 
  Test test;

  SecondWindow() {
    super();
    PApplet.runSketch(new String[] {this.getClass().getSimpleName()}, this);
  }

  void settings() {
    size(200, 200);
  }

  void setup() {
    test = new Test(this);
    background(0, 0, 255);
  }

  void draw() {
    test.display();
  }
}

class Test {
  PApplet applet;

  Test(PApplet _applet) {
    applet = _applet;
  }

  void display() {
    applet.background(0);
  }
  
}