/*   アニメーション実験  Ver 0.10   */
/*                                  */
/*                                  */
/*   by Atsushi         2005/8/20   */


package animation;

import java.awt.*;


class AnimationCanvas extends Canvas
{
	/*   ---   Field   ---   */

	private Animation animation;

	private Image offscreen;

	/*   ---   Constructor   ---   */

	public AnimationCanvas(Animation animation)
	{
		this.animation=animation;
	}

	/*   ---   描画処理   ---   */

	public void paint(Graphics g)
	{
		Dimension size;
		int x,y;
	
		if (offscreen==null)
		{
			offscreen=animation.createImage(this);
			animation.startAnimation();
		}
		
		size=size();								// getSize()
		x=size.width /2-offscreen.getWidth (null)/2;
		y=size.height/2-offscreen.getHeight(null)/2;
		g.drawImage(offscreen,x,y,null);
	}

	public void update(Graphics g)
	{
		paint(g);
	}

	/*   ---   Invalidate   ---   */

	public void invalidate()
	{
		super.invalidate();
		
		if (offscreen!=null) offscreen.flush();
		offscreen=null;
	}

	/*   ---   Finalizer   ---   */

	public void finalize() throws Throwable
	{
		if (offscreen!=null) offscreen.flush();
		
		super.finalize();
	}
}