AnimatorObject.java

/**************************************************************************************
 * fpstiming_tree
 * Copyright (c) 2014-2017 National University of Colombia, https://github.com/remixlab
 * @author Jean Pierre Charalambos, http://otrolado.info/
 *
 * All rights reserved. Library that eases the creation of interactive
 * scenes, released under the terms of the GNU Public License v3.0
 * which is available at http://www.gnu.org/licenses/gpl.html
 **************************************************************************************/

package remixlab.fpstiming;

/**
 * Class implementing the main {@link remixlab.fpstiming.Animator} behavior.
 */
public class AnimatorObject implements Animator {
  protected SeqTimer animationTimer;
  protected boolean started;
  protected long animationPeriod;
  protected TimingHandler handler;

  /**
   * Constructs an animated object with a default {@link #animationPeriod()} of 40
   * milliseconds (25Hz). The handler should explicitly be defined afterwards (
   * {@link #setTimingHandler(TimingHandler)}).
   */
  public AnimatorObject() {
    setAnimationPeriod(40, false); // 25Hz
    stopAnimation();
  }

  /**
   * Constructs an animated object with a default {@link #animationPeriod()} of 40
   * milliseconds (25Hz).
   */
  public AnimatorObject(TimingHandler handler) {
    setTimingHandler(handler);
    setAnimationPeriod(40, false); // 25Hz
    stopAnimation();
  }

  @Override
  public void setTimingHandler(TimingHandler h) {
    handler = h;
    handler.registerAnimator(this);
    animationTimer = new SeqTimer(handler);
  }

  @Override
  public TimingHandler timingHandler() {
    return handler;
  }

  @Override
  public SeqTimer timer() {
    return animationTimer;
  }

  /**
   * Return {@code true} when the animation loop is started.
   * <p>
   * The timing handler will check when {@link #animationStarted()} and then called the
   * animation callback method every {@link #animationPeriod()} milliseconds.
   * <p>
   * Use {@link #startAnimation()}, {@link #stopAnimation()} or {@link #toggleAnimation()}
   * to change this value.
   *
   * @see #startAnimation()
   * @see #animate()
   */
  @Override
  public boolean animationStarted() {
    return started;
  }

  /**
   * The animation loop period, in milliseconds. When {@link #animationStarted()}, this is
   * the delay that takes place between two consecutive iterations of the animation loop.
   * <p>
   * This delay defines a target frame rate that will only be achieved if your
   * {@link #animate()} methods is fast enough.
   * <p>
   * Default value is 40 milliseconds (25 Hz).
   * <p>
   * <b>Note:</b> This value is taken into account only the next time you call
   * {@link #startAnimation()}. If {@link #animationStarted()}, you should
   * {@link #stopAnimation()} first. See {@link #restartAnimation()} and
   * {@link #setAnimationPeriod(long, boolean)}.
   *
   * @see #setAnimationPeriod(long, boolean)
   */
  @Override
  public long animationPeriod() {
    return animationPeriod;
  }

  /**
   * Convenience function that simply calls {@code period(period, true)}.
   *
   * @see #setAnimationPeriod(long, boolean)
   */
  @Override
  public void setAnimationPeriod(long period) {
    setAnimationPeriod(period, true);
  }

  /**
   * Sets the {@link #animationPeriod()}, in milliseconds. If restart is {@code true} and
   * {@link #animationStarted()} then {@link #restartAnimation()} is called.
   *
   * @see #startAnimation()
   */
  @Override
  public void setAnimationPeriod(long period, boolean restart) {
    if (period > 0) {
      animationPeriod = period;
      if (animationStarted() && restart)
        restartAnimation();
    }
  }

  /**
   * Stops animation.
   *
   * @see #animationStarted()
   */
  @Override
  public void stopAnimation() {
    started = false;
    if (timer() != null)
      timer().stop();
  }

  /**
   * Starts the animation loop.
   *
   * @see #animationStarted()
   */
  @Override
  public void startAnimation() {
    started = true;
    if (timer() != null)
      timer().run(animationPeriod);
  }

  /**
   * Restart the animation.
   * <p>
   * Simply calls {@link #stopAnimation()} and then {@link #startAnimation()}.
   */
  @Override
  public void restartAnimation() {
    stopAnimation();
    startAnimation();
  }

  /**
   * Calls {@link #startAnimation()} or {@link #stopAnimation()}, depending on
   * {@link #animationStarted()}.
   */
  @Override
  public void toggleAnimation() {
    if (animationStarted())
      stopAnimation();
    else
      startAnimation();
  }

  @Override
  public void animate() {
  }

  @Override
  public boolean invokeAnimationHandler() {
    return false;
  }
}