import com.sun.j3d.utils.applet.MainFrame;
import com.sun.j3d.utils.image.*;
import java.awt.print.*;
import java.awt.print.PrinterJob;
import java.awt.print.PrinterGraphics;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.awt.Image;
import java.awt.image.ImageObserver;
import java.io.*;
import java.net.*;
import javax.media.j3d.*;
import javax.vecmath.*;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import com.sun.image.codec.jpeg.*;

/** Class PrintCaptureCanvas3D, 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

     public static void captureImage(PrintCaptureCanvas3D c)
          {
          c.writeJPEG_ = true;
          c.saveJPEG_ = true;
          c.repaint();
          };

    A print button would call a method that looks like

     public static void printJPGImage(PrintCaptureCanvas3D c)
         {
        c.writeJPEG_ = true;
        c.saveJPEG_ = false;
        c.repaint();
         };


    Peter Z. Kunszt
    Johns Hopkins University
    Dept of Physics and Astronomy
    Baltimore MD

Working from Mr. Kunszt's posted class, the following enhancements were added:

BufferedImage img;  was made global to the class.
The image width was made dynamic using this.getWidth() & this.getHeight() methods.
Printing capability was added (this is still buggy however)

Don Casteel 10/24/1999
Dcasteel@usit.net
*/

public class PrintCaptureCanvas3D extends Canvas3D  implements Printable, ImageObserver
     {
        public boolean swapCompleted = false;
     public boolean writeJPEG_;
     private int postSwapCount_;
     public boolean saveJPEG_;
     BufferedImage img;
        FileDialog fileDialog;
        File file;
        File directory;

public PrintCaptureCanvas3D(GraphicsConfiguration gc)
        {
        super(gc);
        postSwapCount_ = 0;
        }

public void addNotify() 
        {
        super.addNotify();
        }; 


    public void postSwap()
         {
        if(writeJPEG_)
               {
               System.out.println("Writing JPEG");
               GraphicsContext3D  ctx = getGraphicsContext3D();
               // The raster components need all be set!
               Raster ras = new Raster
                    (
                    new Point3f(-1.0f,-1.0f,-1.0f),
                    javax.media.j3d.Raster.RASTER_COLOR,
                    0,0,
                    this.getWidth(),this.getHeight(),
                    new ImageComponent2D
                         (
                         ImageComponent.FORMAT_RGB,
                         new BufferedImage
                              (
                              this.getWidth(),
                              this.getHeight(),
                              BufferedImage.TYPE_INT_RGB
                              )
                         ),
                    null
                    );
               ctx.readRaster(ras);
               // Now strip out the image info
               img = ras.getImage().getImage();
               // write that to disk....
               if(saveJPEG_)
                    {
                    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!");
                         };
                    }
               else
                    {
                    printMethod();
                    writeJPEG_ = false;
                    };
               postSwapCount_++;
               }
          swapCompleted = true;
          };

          public int print(Graphics g, PageFormat pf, int pi)
               throws PrinterException
               {
               if (pi >= 1)
                    {
                    return Printable.NO_SUCH_PAGE;
                    }
               Graphics2D g2d = (Graphics2D)g;
               g2d.translate(pf.getImageableX(), pf.getImageableY());
               drawObject(g2d);
               return Printable.PAGE_EXISTS;
               };

          public void drawObject(Graphics2D g2d)
               {
               try
                    {
                    g2d.drawImage(img,new AffineTransform(), this);
                    }
               catch (Exception ex)
                    {
                    ex.printStackTrace();
                    };
               };

        public void printMethod()
                {
                System.out.println("Print Method Called");
                         PrinterJob printJob = PrinterJob.getPrinterJob();
                PageFormat pageFormat = printJob.defaultPage();
                         pageFormat = printJob.validatePage(pageFormat);
                         printJob.setPrintable(this);
                         if (printJob.printDialog())
                              {
                              try
                                   {
                                   printJob.print();
                                   }
                              catch (Exception ex)
                                   {
                                   System.out.println("Exception Caught");
                                   ex.printStackTrace();
                                   };
                              };
                    };
          }