I pretty much reached the same conclusion this afternoon.  I think because of the weak GPU features I'm processor-limited here in execution time.

And it appears JDK 1.6 is simply slower at the general-purpose tasks involved in rendering JCanyon.  Looks like we'll just have to see if it speeds up before release or wait for JDK 1.6.1.

I tried taking the unmodified jcanyon JOGL demo source, building it on Java 1.6 beta 2 (with JOGL beta 5) and running it, and comparing it to Java 1.5.0_07 running with -Dsun.java2d.noddraw=true (and without the opengl pipeline).  This is with the AWT/heavyweight rendering.  The slowdown is less obvious in heavyweight, but is still present.  Once you approach the canyon, Java 1.5 beats Java 1.6 by a few fps consistently.  With the extra slowdown involved in lightweight rendering, the "few fps" slowdown remains but becomes a much higher percentage.  (eg. heavyweight I'd get, perhaps, 17fps->14fps, while in lightweight I'd get 8fps->5fps.)

I guess I'll start with filing a JOGL bug, since this slowdown brings the rendering speed below the threshold at which it appears to be "animation" and turns it into a fast slideshow, and I'd really like to embed 3D in this non-opengl-mode, lightweight application.

I had  -Dsun.java2d.ddscale=true and -Dsun.java2d.d3d=true, and didn't specify noddraw=true.  I'll try those.  Do you think noddraw=true will improve the performance?

I'll also try putting together my version of JCanyon into a self-contained app that can reproduce this behavior.  If I do so, should I submit the bug to Sun or send it elsewhere?

I tried some GLJPanel stuff this past weekend with the latest Java 1.6 beta and it was significantly slower than Java 1.5.  Unfortunately, I will not be able to enable the opengl pipeline, so I'm using the default pbuffer solution.  I would expect, though, that 1.6 would be at least as fast as 1.5 even with the old renderer.  But on my ThinkPad T41 laptop on WindowsXP running the JCanyon demo (modified to use the Swing renderer), I get 8-9fps with Java 1.5, and 3-4fps with Java 1.6.  I think I'm using the latest betas of everything and the latest drivers available for my laptop.