/*
 * com.fc.vrml.image.SFImageObserver
 *
 * Copyright (c) 1996-1998 Finlayson Consulting (FC). All Rights Reserved.
 *
 * FC grants you ("Licensee") a non-exclusive, royalty free, license to use,
 * modify and redistribute this software in source and binary code form,
 * provided that i) this copyright notice and license appear on all copies of
 * the software; and ii) this software is not reverse engineereed without written
 * consent.
 *
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING ANY
 * IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR
 * NON-INFRINGEMENT, ARE HEREBY EXCLUDED. FC AND ITS LICENSORS SHALL NOT BE
 * LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING
 * OR DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL FC OR ITS
 * LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT,
 * INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER
 * CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF
 * OR INABILITY TO USE SOFTWARE, EVEN IF FC HAS BEEN ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 *
 * This software is not designed or intended for use in on-line control of
 * aircraft, air traffic, aircraft navigation or aircraft communications; or in
 * the design, construction, operation or maintenance of any nuclear
 * facility. Licensee represents and warrants that it will not use or
 * redistribute the Software for such purposes.
 *
*/

package com.fc.vrml.image;

import vrml.field.SFImage;
import vrml.field.ConstSFImage;
import java.util.Observer;
import java.util.Observable;

/**
*
* This is for use in VRML 2.0 Script node.  It conforms to <A HREF="http://www.vrml.org/Specifications/VRML97/part1/java.html" target=_top>VRML97 Annex B</A>. The SFImageObserver is constructed with a vrml.field.SFImage.  
* <P>
* The SFImageObserver extends the Observer object.  It is registered with an SFImageConverter.
* <P>
* When the update method is called the SFImage is set to the values of the SFImage data of the 
* getExternalSFImage() method of the SFImageConverter cast from Observable if the image status is 
* ImageConsumer.SINGLEFRAMEDONE or ImageConsumer.STATICIMAGEDONE.
* <P>
*Here is an example script and VRML code.  An SFImageConverter loads the image, and when it is loaded sets the PixelTexture.
*<PRE>
* #VRML V2.0 utf8
*
* DEF S Script{
*   eventOut SFImage image_changed
*   url "ImageLoaderScript.class"
* }
* 
* Shape{
*   appearance Appearance{
*     texture DEF T PixelTexture{}
*   }
*   geometry Box{}
* }
* 
* ROUTE S.image_changed TO T.set_image
* 
* </PRE>
* <PRE>
*
* import vrml.*;
* import vrml.field.*;
* import com.fc.vrml.image.*;
* import java.net.*;
* import java.awt.*;
* 
* </PRE>
* <PRE>
*
* public class ImageLoaderScript extends Script{
*   public void initialize(){
*     SFImage sfimage=(SFImage)getEventOut("image_changed");
*     try{
*       URL url=new URL("http://www.foo.org/graphic.gif");
*       Image image=Toolkit.getDefaultToolkit().getImage(url);
*       SFImageConverter converter=new SFImageConverter();
*       SFImageObserver observer=new SFImageObserver(sfimage);
*       converter.addObserver(observer);
*       image.getSource().startProduction(converter);
*     } catch (MalformedURLException mue){}
*   }
* }
*</PRE>
*  @see com.fc.vrml.image.SFImageConverter
*  @version 0.5
*  @author Ross A. Finlayson
*  @author <A HREF="http://www.tomco.net/~raf/vrmlgroup">FC VRML Group</A>
*/


public class SFImageObserver implements Observer{

	private SFImage _sfimage;

	public SFImageObserver(SFImage sfimage){

		_sfimage=sfimage;

	}

/**
* This method is called by the Observable that has been registered with this upon load notification.  
*  It sets the value of this SFImageObserver's SFImage to the value of the SFImage data of the result of the getExternalSFImage() 
*  call to the SFImageConverter cast to Observable.
*/

	public void update(Observable o, Object arg){

		if ( ((Integer)arg).intValue()==1) return;
		if ( ((Integer)arg).intValue()==4) return;

		ExternalSFImage sfimagedata=((SFImageConverter)o).getExternalSFImage();
		_sfimage.setValue( sfimagedata.getWidth(), sfimagedata.getHeight(), sfimagedata.getComponents(), sfimagedata.getPixels());

	}

}