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[pertteli]

I'm trying to integrate a Xith canvas in my AWT GUI. I seem to get problems with aspect ratio. If I resize the window, the aspect ratio of Xith rendering changes.

This happens with org.xith3d.test.ui.SwingIntegrationTest, too. The rotating sphere becames an ellipse if you resize the window. In any real life application you want the aspect ratio to stay fixed, ie. people's heads aren't supposed to go elliptic depending on the window size. Is there a solution, apart from defining a fixed size fo the canvas?

I'm initializing the GUI this way:

Code:

Xith3DEnvironment env=new Xith3DEnvironment(this);
Canvas3DPanel p=new Canvas3DPanel();
add("Center",p);
Canvas 3D c=p.getCanvas();
env.addCanvas(c);
env.addPerspectiveBranch(createScene());

Is this the correct way?

[Marvin Fröhlich]

You could try to resize the viewport size (in RenderPass) in an inverted way to the canvas aspect ratio. You could register a resize listener at the canvas to automate this. Note: Using the canvas'es resize listener is thread safe.

Marvin

[pertteli]

The following approach seems to work. I didn't need any inverting calculations, just set the viewport size to what the canvas size is.

I implement ComponentListener to get resize events from the canvas:

Code:

class MyTest implements java.awt.ComponentListener {
   RenderPassConfigProvider conf;
   Canvas3D canvas;

   public void componentResized(ComponentEvent e) {
       Rect2i vp=conf.getViewport();
       if (vp==null) vp=new Rect2i();    // seems to be null initially
       vp.setSize(canvas.getWidth(),canvas.getHeight());
       conf.setViewport(vp);
   }

And when initializing the scene:

Code:

   Canvas3DPanel p=new Canvas3DPanel();
   add("Center",p);
   p.addComponentListener(this);
   canvas=p.getCanvas();
   env.addCanvas(canvas);
   RenderPass rp=env.addPerspectiveBranch(createScene());
   conf=rp.getConfig();

It works for a simple test, at least. Any loopholes? Could this become a Xith built-in functionality, because it's practically always needed if you have a resizing canvas?

[Marvin Fröhlich]

The following approach seems to work. I didn't need any inverting calculations, just set the viewport size to what the canvas size is.

Oh, you're right. You only need a regular viewport size.

But don't use the AWT ComponentListener for that. As I said, use the Canvas3D's ResizeListener through this method:

Code:

addResizeListener(ResizeListener2i listener);

By using the AWT ComponentListner you have three problems:

• It is not thread safe.
• You stick your application to JOGL_AWT.
• It is a little more coding with castings to use the AWT listener

It works for a simple test, at least. Any loopholes? Maybe this might become a built-in functionality in Xith, because it's practically always needed if you have a resizing canvas, right?

Yes, this is a good idea.

Marvin