Painting in a thread without offscreen image

I'm trying to develop a good map viewer with java. Now, painting a map can
be a very long task, and the requirements for a good map viewer should be:
* the user can see progress, that is, the map is painted incrementally on the
screen, not offscreen, otherwise the user has to sit and wait looking at
a gray pane for seconds (a complex map may take 20-30 seconds to paint)
* the user can stop rendering, or, if the panel is resized, the rendering should
immediatly restart.
The second requirement could be achieved by painting in a separate thread
onto a BufferedImage and then invoke paint back to copy the image onto
screen, but this approach fails to meet the first requirement... is there any way
to paint directly on the screen without blocking the swing event thread?
Moreover, ins't the hardware acceleration lost by using an offscreen image?

To achieve visibly incremental progress of painting on the panel, probably you can use a JTimer and set the delay to 1000ms. In this frequency you can paint the panel in an incremental fashion. This approach will help you to achieve the other requirement of stopping the progress in the middle. You can provide a button, so that if the user presses the button, then invoke stop() method of timer which eventually stops the progress of the panel. Also if you want, you can restart() the progress from the point where it got stopped previously, by invoking restart() method of timer.
Obviously, you should have a method which does all your painting and so on. Here JTimer can be helpful only in stopping, restarting and delaying the progress. Finally, make sure that the painting method is handled by JTimer alone.
Hope this helps.

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PB: PixelGrabber, offscreen Image, Windows 98, ie5

Hello,
I've got a problem with a bug that occurs under Windows 98, and ie5.
This is the code of a little applet that works fine under Windows NT, but not under Windows 98:
This applet draws 3 colors in a square, and use the grabPixel method for catching the pixels of the image and create another image with those pixels.(the image should be the same)
The problem is that the grabPixel method changes the colors of the pixels. It occurs only with an offscreen Image (that means an Image created with the createImage(w, h) method). there is no problem with a MemoryImageSource, for example.
I just notice that the ColorModel of an offscreen Image is not the same as the default ColorModel:
colorModel: java.awt.image.DirectColorModel = {...}
red_mask: int = 0xf800 (instead of 0x00ff0000 )
green_mask: int = 0x7e0 (instead of 0x0000ff00 )
blue_mask: int = 0x1f (instead of 0x000000ff)
alpha_mask: int = 0x0 (instead of 0xff000000)
red_offset: int = 0xb
green_offset: int = 0x5
blue_offset: int = 0x0
alpha_offset: int = 0x0
red_scale: int = 0x1f
green_scale: int = 0x3f
blue_scale: int = 0x1f
alpha_scale: int = 0x0
But i don't know how to solve the bug.
Here is the code :
import java.awt.*;
import java.awt.image.*;
import java.applet.*;
public class AppletFlush extends Applet implements Runnable{
Thread anim;
Image memimg;
boolean bool;
Image offImage;
Graphics offGraphics;
     public void init() {
     public void start() {
     anim = new Thread(this);
     anim.start();
bool = true;
offImage = this.createImage(100, 100);
offGraphics = offImage.getGraphics();
     public synchronized void stop() {
     anim = null;
     notify();
     public synchronized void run() {
     while (Thread.currentThread() == anim) {
int[] pixels = new int[100 * 100];
int color = 0;
//set the pixels of a squared image that contains 3 colors (this is my reference image)
if (bool)
bool = false;
for (int i=0; i<100; i++)
if (i<33)
color = 0xffff0000;
else if (i<66)
color = 0xff00ff00;
else
color = 0xff0000ff;
for (int j=0; j<100; j++)
pixels[i*100 + j] = color;
else
//grab the pixels of the offscreen image(here is the problem)
PixelGrabber pg = new PixelGrabber(offImage, 0, 0, 100, 100, pixels, 0, 100);
try
pg.grabPixels();
catch (InterruptedException ex)
System.out.println("erreur pendant gragPixels !!!");
//create the new image with the pixels
MemoryImageSource imgsrc = new MemoryImageSource(100, 100, pixels, 0, 100);
memimg = createImage(imgsrc);
//draw the image in the offscreen image
offGraphics.drawImage(memimg, 0, 0, null);
          repaint();
          try {wait(1000);} catch (InterruptedException e) {return;}
     public void paint(Graphics g) {
     // display the offscreen image
     g.drawImage(offImage, 0, 0, this);
PLEASE HELP !
YaYa

try
public void paint(Graphics g )
if((_offScreen != null)&&(offScreenImage != null))
// put your stuff here
else
update(g);
g.dispose();
g.finalize();
return;
public void update(Graphics g)
if( offScreenImage == null)
offScreenImage = this.createImage( width, height );
if( _offScreen == null)
_offScreen = offScreenImage .getGraphics();
paint(g);
}

How to draw a JPanel in an offscreen image

I am still working on painting a JPanel on an offline image
I found the following rules :
- JPanel.setBounds shall be called
- the JPanel does not redraw an offline image, on should explicitly override paint()
to paint the children components
- the Children components do not pain, except if setBounds is called for each of them
Still with these rules I do not master component placement on the screen. Something important is missing. Does somebody know what is the reason for using setBounds ?
sample code :
private static final int width=512;
private static final int height=512;
offScreenJPanel p;
FlowLayout l=new FlowLayout();
JButton b=new JButton("Click");
JLabel t=new JLabel("Hello");
p=new offScreenJPanel();
p.setLayout(l);
p.setPreferredSize(new Dimension(width,height));
p.setMinimumSize(new Dimension(width,height));
p.setMaximumSize(new Dimension(width,height));
p.setBounds(0,0,width,height);
b.setPreferredSize(new Dimension(40,20));
t.setPreferredSize(new Dimension(60,20));
p.add(t);
p.add(b);
image = new java.awt.image.BufferedImage(width, height,
java.awt.image.BufferedImage.
TYPE_INT_RGB);
Graphics2D g= image.createGraphics();
// later on
p.paint(g);
paint method of offScreenPanel :
public class offScreenJPanel extends JPanel {
public void paint(Graphics g) {
super.paint(g);
Component[] components = getComponents();
for (int i = 0; i < components.length; i++) {
JComponent comp=(JComponent) components;
comp.setBounds(0,0,512,512);
components[i].paint(g);

Unfortunately using pack doesn't work, or I didn't use it the right way.
I made a test case, eliminated anything not related to the problem (Java3D, applet ...). In the
test case if you go to the line marked "// CHANGE HERE" and uncomment the jf.show(), you have
an image generated in c:\tmp under the name image1.png with the window contents okay.
If you replace show by pack you get a black image. It seems there still something.
simplified sample code :[b]
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import com.sun.j3d.utils.applet.*;
import com.sun.j3d.utils.image.*;
import com.sun.j3d.utils.universe.*;
import java.io.*;
import java.awt.image.*;
import javax.imageio.*;
public class test {
private static final int width=512;
private static final int height=512;
public test() {
JPanel p;
BorderLayout lay=new BorderLayout();
java.awt.image.BufferedImage image;
// add a JPanel with a label and a button
p=new JPanel(lay);
p.setPreferredSize(new Dimension(width,height));
JLabel t=new JLabel("Hello");
t.setPreferredSize(new Dimension(60,20));
p.add(t,BorderLayout.NORTH);
p.setDebugGraphicsOptions(DebugGraphics.LOG_OPTION );
// show the panel for debug
JFrame jf=new JFrame();
jf.setSize(new Dimension(width,height));
jf.getContentPane().add(p);
[b]
// CHANGE HERE->
jf.pack();
//jf.show();
// create an off screen image
image = new java.awt.image.BufferedImage(width, height,
java.awt.image.BufferedImage.TYPE_INT_RGB);
// paint JPanel on off screen image
Graphics2D g= image.createGraphics();
g.setClip(jf.getBounds());
System.err.println("BEFORE PAINT");
jf.paint(g);
System.err.println("AFTER PAINT");
// write the offscreen image on disk for debug purposes
File outputFile = new File("c:\\tmp\\image1.png");
try {
ImageIO.write(image, "PNG", outputFile);
} catch (Exception e) {
System.err.println(e.getMessage());
g.dispose();
jf.dispose();
public static void main(String[] args) {
test t=new test();
}

Convert RTFD to Doc (without losing images)

Hello!
Is it possible to convert RTFD-format files to Microsoft Word (doc) format - without losing images?
As a longtime Mac user, I have a multitude of RTF and RTFD files. I want to be able to access the contents of these files on platforms other than OS X (eg: Windows).
RTFD is not supported outside OS X. I'll qualify this by acknowleding that since RTFD files are OS X Packages, they show up in Windows as a folder containing image files and an RTF file; some people conclude that this is acceptable since, strictly speaking, its readable by windows. I disagree because its fiddly and hack-like rather than simple, recognizable and practical like a .doc file.
Given that I can open an RTFD file, copy/paste it's content (images and text) to a new blank Microsoft Word document and save it as .doc, it seems to me that I should be able to automate those steps using AppleScript or Automator.
I've Googled for a solution to this but no-one else is talking about it, with the exception of:
- the command-line 'textutil' converter, but that creates ascii files that are necessarily stripped of all images
- converting to HTML, but that creates more than a single file (an HTML file plus a folder containing the images)
Am I missing something really obvious?
Many thanks!
Peter

Hi duncang!
The command-line 'textutil' app strips out images and so is useless for my purposes. As you pointed out, the solutions suggested by MrHoffman and Etresoft are incorrect.
A solution for my original post for this thread: use Apple's Pages for Mac (part of the iWork '09 Suite). I have succesfully converted thousands of RTFD files containing images into Microsoft Word (.doc) format.
If you have a lot of RTFD files to convert, then I recommend using an applescript to automate the process.
The applescript wizard Yvan Koenig (link) has very kindly provided a useful applescript for Pages '09 to automatically convert batches of RTF and RTFD files into Word or PDF. That guy knows what he's talking about and should be knighted for his efforts and kindness.
Look on his Box dot net public folder (link) for a file called 'batch_Pages2Doc.zip' (created Jan 31 2013). Here is the path to the file: / for_iWork'09 / for_Pages09 / batch_Pages2Doc.zip
- open the script in 'AppleScript Editor' on your Mac
- read the useful instructions he provides in comments within the script
- save it as an application so you can use it as a droplet onto which you can drag multiple RTFD files
- you can even edit the script using his instructions so it exports PDF as well as Doc
- it saves output to a 'wasPages_now_doc' folder on either your desktop or in your Documents folder
I'm running:
- Mac OS X 10.8.4
- iWork 2009 (retail boxed edition, not Mac App Store edition)
I hope this helps. It took me months to discover the solution to my original post.
-Peter

Copy offscreen image to applet

I drew points to an offscreen Image and tried to copy it to my applet, but the applet is just white.
my code:
    public void paint (Graphics g)
        Image Drawing = Background;
        Drawing.getGraphics ().setColor (Paint);
        int Index = 0;
        while (Index < points.size ())
            Drawing.getGraphics ().drawLine ((int) Math.round (((Point) poins.get (Index)).getX ()), (int) Math.round (((Point) points.get (Index)).getY ()), (int) Math.round (((Point) points.get (Index)).getX ()), (int) Math.round (((Point) points.get (Index)).getY ()));
            Index = Index + 1;
        g.drawImage (Drawing, 0, 0, this);
    }what am I doing wrong?
(oh yeah, and is there a better way to draw points, or do I really have to draw 1x1 pixel lines?)

It is true that turning off graphics acceleration eliminates the problem, but you can't publish an applet that requires every user turn off hardware acceleration on their PC. The problem has to be either fixed in the awt (unlikely since 1.6.10 is at RC) or bypassed in the applet.
So, if you are reading this because you have a production applet broken by the changes in Java 1.6.10, I am afraid you are going to have to make changes to your paint routine to avoid the applet using any drawImage coordinates that reference areas outside the clip region of the graphics context.

How can I attach an image without the image is in the email body? (using the new mail the Lion)

How can I attach an image without the image is in the email body? (using the new mail the Lion)
I want in attachment, not in the body mail.

I think your only solution is to zip the image files first and then attach them.
Read this from a site I found:
Sending Graphical Attachments -- When you attach a graphical image to your message, the recipient of your message sees the image inline (that is, in the body of the message) if her email client supports inline display. ("Take Control of Email with Apple Mail" contains a table listing the capabilities of popular Mac and PC email clients.) If a client does not support inline display (or the recipient has turned off the inline display option), the file appears as an attachment that must be opened in a separate program.
On the one hand, an inline image is easier for the recipient to see - all she has to do is look at it. On the other hand, inline images can be frustrating to scroll through. If you do not wish to send a graphical image inline, you must compress the file before attaching it - Mail, sadly, lacks a built-in compression option, though fortunately for Panther users, the Finder offers Zip compression without requiring a separate application.
Note that when you compose a new message, Mail always shows attachments in the body of your message. You can manually drag them somewhere else, but many email clients display all attachments in a separate list, regardless of where you place them in the message body.
If you paste an image into a message or drag & drop an image from another window (say, a Web browser), Mail converts the raw image data to an attachment in TIFF format. On the other hand, if you drag & drop the icon of an image file (or use the Attach button to locate the file using the file browser), Mail leaves the attached image in its original format. This difference is significant, because although most email clients can display JPEG images just fine, support for TIFF - especially in non-Mac email clients - is less common. If possible, I suggest attaching image files as opposed to pasting or dragging in raw image data.

Is there a way to view earlier messages in a thread without going through each day? Also, can you make a photo album from the same text thread without going back to the beginning?

Is there a way to view earlier messages in a thread without going through each day? Also, can you make a photo album from the same text thread without going back to the beginning?

Turn Settings > General > Accessibility > Zoom to ON.

Any way to open new browser window without using image maps?

Is there any way to open new browser window without using image maps? My code works fine in Firefox, but not in IE. There are 2 problems in IE: 1st is that the thumbnail images move up within their own borders & 2nd that when you click on an image it does open up a new browser window, but also redirects to the index page (in this case it's just a placeholder index page - the new one I've called index_new.html for the time being).
Here is the link:
http://www.susieharperdesigns.com/gallery_beads.html
Any help is greatly appreciated.

Your missing a value on the HREF. In your code you have this:
<area shape="rect" coords="-24,-9,106,144" href=" " onclick="MM_openBrWindow('gallery_bead1.html','','width=255,height=360')" />
</map></div>
and it should be this:
<area shape="rect" coords="-24,-9,106,144" href="javascript:void()" onclick="MM_openBrWindow('gallery_bead1.html','','width=255,height=360')" />
</map></div>
If you fix the code on all your beads, it should work.
Nancy O.
Alt-Web Design & Publishing
Web | Graphics | Print | Media Specialists
http://alt-web.com/
http://twitter.com/altweb
http://alt-web.blogspot.com

Gallery files included on a page without gallery images/thumbnails

Hi,
I included the .js files for the gallery on a page without
gallery images/thumbnails.
The effect is, that the first image with a link on that page
gets a yellow border (as normally the first thumbnail does).
To correct the problem, I changed the code in line 44 of
SpryThumbViewer.js:
from
this.tnImageSelector = "a[href] > img";
to
this.tnImageSelector = "div.thumbnail a[href] > img";
(of course, you have to put a <div
class="thumbnail">...</div> around an image on real
gallery pages, so that they work there)
Do you see any problems with the changed code? Could it be
changed in the official release?
Greetings,
Sven

Live View, Code View or Design View?
Have you validated your code to check for errors?
CSS - http://jigsaw.w3.org/css-validator/
HTML - http://validator.w3.org/
You could comment out your links to external scripts and CSS Files.

To turn off styles in Design View only, go to View > Style Rendering > untick Display Styles. Or consider using a Design-Time Style Sheet.
Dreamweaver Help | Use Design-Time style sheets
To speed things up a bit, try these tips:
1. Edit -> Preferences -> Code Hints -> Disable description tooltips
2. Edit -> Preferences -> Highlighting -> Untick both Live Data Untranslated and Translated
3. Edit -> Preferences -> Sync Settings -> Untick all in sync settings
Nancy O.

Associating artwork with songs without embedding images in song files

Is it possible to associate artwork with songs in iTunes without embedding images in song files?
I'd like to see album covers in iTunes but don't want to waste the storage space on my iPod.
Thanks

You can add your own artwork (for covers iTunes does not get) to coverflow wihtout embedding it into the ID3 tags.
See this -> http://www.macosxhints.com/article.php?story=2006100111071871
I haven't tried it yet but others have had success.

How to "kill" AWT Event Queue thread without using System.exit()?

When I run my program and the first GUI window is displayed a new thread is created - "AWT-Event Queue". When my program finishes, this thread stays alive and I think it causes some problems I have experienced lately.
Is there any possibility to "kill" this thread without using System.exit() (I can't use it for some specific reasons)

All threads are kept alive by the JVM session. When you use System.exit(int) you kill the current session, thus killing all threads. I'm not sure, though...
What you could do, to make sure all threads die, is to make ever thread you start member of a thread group. When you want to exit you app, you kill all the threads in the thread group before exit.
A small example:
//Should be declared somewhere
static ThreadGroup threadGroup = new ThreadGroup("My ThreadGroup");
class MyClass extends Thread {
super(threadGroup, "MyThread");
Thread thread = new Thread(threadGroup, "MySecondThread");
void exit() {
//Deprecated, seek alternative
threadGroup.stop();
System.exit(0);
}

It should be possible to close a thread without saying it's answered.

It should be possible to close a thread without saying it's answered.
Maybe closed - resolved or closed - not resolved.
Edited by: Mike Angelastro on Jan 29, 2010 6:43 AM

Mark it answered may not mean your question is answered. If you do not satisfy all replies, you simply do not assign any points. Everyone will know it is not answered. You may post the last message as No satisfied answer.
Thanks,
Gordon

How can I put another image without its associated sound on an audio (without its image) ?

IMovie 11 : how can I put one image without its associated sound on an audio (without its image) ? thanks

Hi
As iMovie doesn't orient after Time - but only after Video/Photo clips is this not so easy to do.
I use black photos as Dummy clips - and put them into a new project first
then I add the Music I want
Then I drop the Video-clip (that I realy want) ontop of the black dummy photo - Where it's supposed to be - THEN IF advanced tools are selected (in iMovie preferences) there will be a Drop-Down menu and here I can select to do a Cutaway - and select not to add the audio from it (or in wave-form just silence it out)
Yours Bengt W

OCR without rotating image

In Acrobat 9 I can't find any setting to disable image automatic rotating of recognized documments by OCR.
I have usually very exact position of originals and I don't need this teature.
Besides, after this rotating by 0,0... degrees, Acrobat ruins image and add some linear deformates.
Please, help me how to make OCR without rotate image.

I am assuming that when you open your photo in CS5 that the layer is automatically locked?
If yes, then you can right click that layer and there is an option at the top called "Layer From Background...".
This unlocks that layer without having to duplicate it.
To rotate an image without changing dimensions of the actual photo? When you rotate an image the width and the height dimensions are switch depending on how you rotate.
Under Edit>>Transform, you will get 4 different options to rotate.
The rotate at the top is to manually rotate the image. The other rotates are presets which might be what your after.

Drawing a font on an offscreen image

I'm trying to draw a font on my own offscreen image but I had to implement a few tweaks to get it to work and I would like to know how to do it properly. Here's my code:
private int[] getPrintMetrics(Font fnt, String txt) {
    BufferedImage bi = new BufferedImage(1, 1, BufferedImage.TYPE_INT_RGB);
    Graphics2D bg = (Graphics2D)bi.getGraphics();
    FontRenderContext frc = bg.getFontRenderContext();
    TextLayout tl = new TextLayout(txt, fnt, frc);
    int ret[] = new int[2];
    ret[0] = (int)tl.getBounds().getWidth();
    ret[1] = (int)(tl.getBounds().getHeight() * 1.5);
//    ret[0] = (int)tl.getPixelBounds(frc, 0, 0).getWidth();
//    ret[1] = (int)(tl.getPixelBounds(frc, 0, 0).getHeight() * 1.5);
    //BUG! WHY IS HEIGHT TOO SMALL? I HAVE TO ADD 50%
    return ret;
public void print(Font fnt, int x, int y, String txt, int clr) {
    int size[] = getPrintMetrics(fnt, txt);
    BufferedImage bi = new BufferedImage(size[0], size[1], BufferedImage.TYPE_INT_RGB);
    Graphics2D bg = (Graphics2D)bi.getGraphics();
    FontRenderContext frc = bg.getFontRenderContext();
    TextLayout tl = new TextLayout(txt, fnt, frc);
    //this method draws the outline only
    Shape shape = tl.getOutline(AffineTransform.getTranslateInstance(0, tl.getBounds().getHeight()));
    bg.setColor(new Color(clr));
    bg.draw(shape);
    bg.setColor(new Color(clr));
    bg.setFont(fnt);
    bg.drawString(txt, 0, -1 * tl.getBaselineOffsets()[tl.getBaseline()+2]);   //BUG! HOW DO I KNOW WHICH BASELINE TO USE?
    putPixels(bi.getRGB(0,0,size[0],size[1],null,0,size[0]), x, y, size[0], size[1], 0);
}putPixels() is my own member that will draw to my own image buffer.
1) Why must I multiply the height by 1.5 in the getPrintMetrics() ?
2) How do I know which baseline to use (I just hacked it).
Thanks.

Why is the height so small?
new BufferedImage(1, 1, BufferedImage.TYPE_INT_RGB);The graphics context for this BufferedImage is very small.
For more size increase the width and height dimensions.
Try this.
import java.awt.*;
import java.awt.font.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
public class GraphicsExercise {
    private JLabel getContent() {
        BufferedImage image = createImage();
        Graphics2D g2 = image.createGraphics();
        g2.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING,
                            RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
        g2.setPaint(Color.blue);
        Font font = new Font("dialog", Font.PLAIN, 36);
        g2.setFont(font);
        FontRenderContext frc = g2.getFontRenderContext();
        String s = "Hello World";
        LineMetrics metrics = font.getLineMetrics(s, frc);
        float height = metrics.getAscent() + metrics.getDescent();
        float width = (float)font.getStringBounds(s, frc).getWidth();
        float x = (image.getWidth() - width)/2f;
        float y = (image.getHeight() + height)/2 - metrics.getDescent();
        g2.drawString(s, x, y);
        g2.dispose();
        return new JLabel(new ImageIcon(image), JLabel.CENTER);
    private BufferedImage createImage() {
        int w = 240;
        int h = 165;
        int type = BufferedImage.TYPE_INT_RGB;
        BufferedImage image = new BufferedImage(w, h, type);
        Graphics2D g2 = image.createGraphics();
        g2.setBackground(UIManager.getColor("Panel.background"));
        g2.clearRect(0,0,w,h);
        g2.dispose();
        return image;
    public static void main(String[] args) {
        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.getContentPane().add(new GraphicsExercise().getContent());
        f.pack();
        f.setLocation(200,200);
        f.setVisible(true);
}

Painting in a thread without offscreen image

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