newbi needs help :(

OpenGL Development JOGL Development
#1

Hello All,

I’m new to OpenGL and JOGL but after a little struggle I’m getting somewhere
I’ve got a little Swing app with a GLCanvas in it where I draw a cube and map some textures on the sides. Also have some sliders in the app that let you translate/rotate the cube. So I’m feelin proud of myself, I make it into a webstart app and tell a buddy of mine to check it out. When he views it the cube is solid white, no textures. I developed it on a linux box but tested it on a Win2K machine before trying to show it off. After a little more testing I find I can run it on serveral Win2K boxes but I have on where it does same thing, cube is solid white. The machine I have where it doesn’t work correctly is a fairly new Dell with a GForce 4 video card so I don’t think it’s hardware. I turned on the webstart debugger console and I don’t see any errors. Anybody seen similar behaviour before or have any idea what I’m doing worng or how to track it down??

Thanx
Dave

#2

It’s all about how you load your texture buddy, sometimes it works just fine on your machine, but when converted into a webstart application, things don’t go as well as you planned.

Here’s some code to download images (PNG, GIF, JPG, TGA) from anywhere using either a desktop demo or a webstart application
Link

#3

Java Cool Dude,
Thanks for the tip.
I did have trouble loading the textures when I went from a straight java app to a webstart app, but I’ve gotten over that hump. Now, even after sucssefully converting my app into a webstart app, it behaves differently on different machines. The image is bundled up in the jar file with the webstart app itself and I load it like this

private BufferedImage readPNGImage(String resourceName)
{
try
{
URL url=Main.class.getResource(resourceName);
if (url == null)
{
throw new RuntimeException("Error reading resource " + resourceName);
}
BufferedImage img = ImageIO.read(url);
java.awt.geom.AffineTransform tx = java.awt.geom.AffineTransform.getScaleInstance(1, -1);
tx.translate(0, -img.getHeight(null));
AffineTransformOp op = new AffineTransformOp(tx, AffineTransformOp.TYPE_NEAREST_NEIGHBOR);
img = op.filter(img, null);
return img;
}
catch (IOException e)
{
throw new RuntimeException(e);
}
}
where Main is my top level class containing program entry point

Thanks for the code snippet, I’ll mess with it and see if I get any different results

Dave

#4

Probably a ImageIO bug:
http://developer.java.sun.com/developer/bugParade/bugs/4764639.html

Try loading the image data into a byte[] and creating the image fram that.

#5

Like I said try the stuff that I linked in my previous post, it’s known to work for sure.
I tired different approaches as well using MyClass.class.getResource etc and they all failed miserably to cope with JWS, however using this method


    BufferedImage bufferedImage = null;
    ClassLoader  fileLoader  = ImageLoader.class.getClassLoader();
    InputStream  input       = fileLoader.getResourceAsStream(textureLocation);

    try {
      if(input == null)
        input = new FileInputStream(textureLocation);

      bufferedImage = javax.imageio.ImageIO.read(input);
    }
    catch( Exception e){
    }

will help you out a lot

#6

Hi,
Thanks for the help
Where does this ImageLoader class come from

ClassLoader fileLoader = ImageLoader.class.getClassLoader();

I don’t see it in the java API docs
I googled it and found several third party classes

Dave

#7

Check out my link :wink:

#8

Ok, I created a class like this

package joglTest;

import java.awt.image.DataBufferByte;
import java.awt.image.BufferedImage;
import java.io.FileInputStream;
import java.io.InputStream;

/**
*

  • @author drobbins
    */
    public class ImageLoader {

    /** Creates a new instance of ImageLoader */
    public ImageLoader() {
    }
    public BufferedImage loadImage(String resourceName)
    {
    BufferedImage bufferedImage = null;
    java.lang.ClassLoader fileLoader = ImageLoader.class.getClassLoader();
    java.io.InputStream input = fileLoader.getResourceAsStream(resourceName);

     try {
      if(input == null)
        input = new FileInputStream(resourceName);

      bufferedImage = javax.imageio.ImageIO.read(input);
 }
 catch( Exception e){
 }
 return bufferedImage;

    }

}

And in my app I create an instance of ImageLoader and call it’s load Image method with resourceName = “images/picture.png”, and

java.io.InputStream input = fileLoader.getResourceAsStream(resourceName);

returns null.
my ImageLoader class is in the top level directory of my app and the png is in a sub-directory named images. At this point this is just a java application, no webstart or jar files involved. See what I’m doing wrong???

Dave

#9

Use this hierarchy (sp?)
http://www.users.xith.org/JavaCoolDude/JWS/Xith3D/WaterCubeMap/source/

#10

JCD,

I ask this at the risk of sounding dense, but could you tell me where in this hierachy

http://www.users.xith.org/JavaCoolDude/JWS/Xith3D/WaterCubeMap/source/

the ImageLoader class gets used

Thanx for all the help
Dave