/*
  File: CapturingCanvas3D.java

  University of Applied Science Berne,HTA-Biel/Bienne,
  Computer Science Department.

  Diploma thesis J3D Solar System Simulator
  Originally written by Marcel Portner & Bernhard Hari (c) 2000
  
  CVS - Information :
  
  $Header: /var/cvsreps/projects/c450/2000/sss3d/source_diploma/sss3d/utils/CapturingCanvas3D.java,v 1.2 2000/12/06 11:09:01 portm Exp $
  $Author: portm $
  $Date: 2000/12/06 11:09:01 $
  $State: Exp $
  
*/
package sss3d.utils;

import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.*;
import javax.media.j3d.*;
import javax.vecmath.Point3f;
import com.sun.image.codec.jpeg.*;

/**
 * Class CapturingCanvas3D, using the instructions from the Java3D 
 * FAQ pages on how to capture a still image in jpeg format.
 *
 * A capture button would call a method that looks like
 * 
 * <pre>
 *  public static void captureImage(CapturingCanvas3D MyCanvas3D) {
 *    MyCanvas3D.writeJPEG_ = true;
 *    MyCanvas3D.repaint();
 *  }
 * </pre>
 *
 * Peter Z. Kunszt
 * Johns Hopkins University
 * Dept of Physics and Astronomy
 * Baltimore MD
 *
 * @author Marcel Portner & Bernhard Hari
 * @version $Revision: 1.2 $
 */
public class CapturingCanvas3D extends Canvas3D {

   public boolean writeJPEG_;
   private int postSwapCount_;

   /**
    * Constructor that generate a Canvas3D.
    *
    * @param gc  the GraphicsConfiguration
    */
   public CapturingCanvas3D(GraphicsConfiguration gc) {
      super(gc);
      postSwapCount_ = 0;
      writeJPEG_ = false;
   }

   /**
    * Override Canvas3D's postSwap method to save a JPEG of the canvas.
    */
   public void postSwap() {
      if(writeJPEG_) {
         System.out.println("Writing JPEG");
         int dimX = this.getScreen3D().getSize().width;
         int dimY = this.getScreen3D().getSize().height;

         // The raster components need all be set!
         Raster ras = new Raster(new Point3f(-1.0f, -1.0f, -1.0f),
                                 Raster.RASTER_COLOR,
                                 0, 0,
                                 dimX, dimY,
                                 new ImageComponent2D(ImageComponent.FORMAT_RGB,
                                                      new BufferedImage(dimX, dimY,
                                                                        BufferedImage.TYPE_INT_RGB)),
                                 null);
 
         GraphicsContext3D  ctx = getGraphicsContext3D();
         ctx.readRaster(ras);
 
         // Now strip out the image info
         BufferedImage img = ras.getImage().getImage();
 
         // write that to disk....
         try {
            FileOutputStream out = new FileOutputStream("Capture" + postSwapCount_ + ".jpg");
            JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
            JPEGEncodeParam param = encoder.getDefaultJPEGEncodeParam(img);
            param.setQuality(0.9f,false); // 90% qualith JPEG
            encoder.setJPEGEncodeParam(param);
            encoder.encode(img);
            writeJPEG_ = false;
            out.close();
         } catch ( IOException e ) {
            System.out.println("I/O exception!");
         }
         postSwapCount_++;
      }
   }
}