Transitionable.pde

/**
 * Class for objects whitch transition between frames in the app
*/
public abstract class Transitionable extends Obj {
  // Set to true to begin transitioning!
  public boolean trans = false;
  // Done transitioning
  public boolean middle = false;
  public boolean done = false;

  public boolean paused = false;

  protected void postSetup() {
    super.postSetup();

    m.transIn.reset();
    m.transOut.reset();
  }

  protected void preUpdate() {
    super.preUpdate();

    if (middle && trans) {
      transition();
    }
  }

  protected void postUpdate() {
    super.postUpdate();

    if (!middle && trans) {
      transition();
    }
  }

  private void transition() {
    if (paused) return;

    if (!m.transIn.done) {
        m.transIn.update();

        if (m.transIn.beforeDone) {
          middle = true;
          shouldUpdate = false;
          onTransOutBegin();
        }
      }
    else {
      if (!m.transOut.done) {
        m.transOut.update();
      }
    }

    if (m.transIn.done && m.transOut.done) {
      // When the trans is done
      onDone();
    }
  }

  protected void clean() {
    m.transIn.reset();
    m.transOut.reset();
  }

  protected void onDone() {
    trans = false;
    done = true;
    middle = false;

    clean();
  }

  // Method whitch inheriting classes should implement
  // for cleanup
  protected void onTransOutBegin() {}

  public Transitionable(Snap app) { super(app); }
}