source: git/Singular/LIB/surfex/RayPanel.java @ 3de2ca

////////////////////////////////////////////////////////////////////////
//
// This file RayPanel.java is part of SURFEX.
//
////////////////////////////////////////////////////////////////////////

////////////////////////////////////////////////////////////////////////
// 
// SURFEX version 0.90.00
// =================
//
// Saarland University at Saarbruecken, Germany
// Department of Mathematics and Computer Science
// 
// SURFEX on the web: www.surfex.AlgebraicSurface.net
// 
// Authors: Oliver Labs (2001-2008), Stephan Holzer (2004-2005)
//
// Copyright (C) 2001-2008
// 
// 
// *NOTICE*
// ========
//  
// This program is free software; you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the
// Free Software Foundation ( version 3 or later of the License ).
// 
// See LICENCE.TXT for details.
// 
/////////////////////////////////////////////////////////////////////////

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Toolkit;
import java.net.URL;

import javax.swing.*;
import javax.swing.SwingUtilities;

//////////////////////////////////////////////////////////////
//
// class RayPanel
//
//////////////////////////////////////////////////////////////

public class RayPanel extends JPanel {
        private Image theIMG = null;

        Graphics offGraphics;

        Dimension offDimension;

        Image offImage;
        
        

        String picname = "";

        RayPanel() {
        } 
        
        
        
        public void changeBackground(String pn) {
                picname = pn;
                if (theIMG != null) {
                        theIMG.flush();
                        theIMG = null;
                }
                //     if (theIMG != null) {
                //       theIMG.flush();
                //     }
                //    theIMG = Toolkit.getDefaultToolkit().getImage(picname);

                SwingUtilities.updateComponentTreeUI(this);
                repaint();
        }

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

        //
        public void update(Graphics g) {
                //  System.out.println("update...");
                if (1 == 1) {
                        Dimension d = getSize();
                        if ((offGraphics == null) || (d.width != offDimension.width)
                                        || (d.height != offDimension.height)) {
                                offDimension = d;
                                offImage = createImage(d.width, d.height);
                                offGraphics = offImage.getGraphics();
                        }

                        if (theIMG == null) {
                                //  System.out.println("null IMG:"+picname+"...");
                                if (picname.length() < 5) {
                                        if (picname.length() > 0) {
                                                //  System.out.println("get IMG"+picname+"...");
                                            theIMG = Toolkit.getDefaultToolkit().getImage(picname);
                                            //  System.out.println("got IMG:"+picname+".");
                                        }
                                } else {
                                        if ((picname.substring(0, 5)).equals("http:")) {
                                                //  System.out.println("try to load:"+picname);
                                                try {
                                                        theIMG = Toolkit.getDefaultToolkit().getImage(
                                                                        new URL(picname));
                                                        //    System.out.println("got image");
                                                } catch (Exception ex) {
                                                        System.out.println(ex.toString());
                                                }
                                        } else {
                                                //  System.out.println("get IMG"+picname+"...");
                                                theIMG = Toolkit.getDefaultToolkit().getImage(picname);
                                                //  System.out.println("got IMG:"+picname+".");
                                                //      theIMG = Toolkit.getDefaultToolkit().getImage(picname);
                                        }
                                }
                        }
                        if (theIMG != null) {
                                //  System.out.println("draw IMG");
                                //    offGraphics.setColor(Color.black);
                                //    offGraphics.clearRect(0,0,d.width,d.height);
                                //    offGraphics.setClip(0,0,d.width,d.height);
                                offGraphics.drawImage(theIMG, 0, 0, d.width, d.height, this);
                                //    System.out.println("image drawn");
                        }

                        g.drawImage(offImage, 0, 0, this);
                }
        }
} // end class RayPanel