[gl4java-usergroup] GLCanvas Dispose on NT

[<NM...@th...>]

Hi,

My application needs to swap a GLCanvas and a JPanel in and out of a GUI
Container(JSplitPane). Currently I am destroying a GLCanvas with cvsDispose
() and then rebuilding by recalling the constructor with each swap.

What is the proper way to dispose of a GLCanvas? Currently, I am executing
the following code :

try {
      cvsDispose();
} catch (Exception e) {
      e.printStackTrace();
}

On a WinNT machine this call causes a EXCEPTION_ACCESS_VIOLATION outside of
the Java VM. It is happening in the gljDestroyNative() method in
OpenGL_Win32_jawt.c when the native disp_wglDeleteContext(gc) call is
made(Line 713).

if(ret==JNI_TRUE)
{
      if(gc!=0) {
            disp__wglDeleteContext(gc);
      }
}

I can wrap the code in a __try/__except but when I do my application
freezes for up to a minute due to, I assume, a weird threading issue.

I've tested my application on a Win95 machine and there is no error. Only
NT. Also, I have the most recent release 2.8.2.0, Java 1.3.1, and the most
current GL dlls.

My questions are :
1) Am I making the right call to properly dispose of a GLCanvas?
2) Is this a known error? Is there a work around I am not aware of?
3) If there is no work around, can anyone suggest a way of disabling and
then re-enabling a GLCanvas without actually destroying it?  I have tried
many combinations using calls : setVisible(), setGLEnabled() but the
context is never re-enabled. I think it has something to do with the JPanel
being placed on top of the GLCanvas. Is there a combination of calls anyone
can recommend?

Your help is GREATLY appreciated.

Thanks,
Noah Keen

PS: FYI : In a recent post about platform independent gaming on
slashdot.org the following comments were made about GL4Java.
http://slashdot.org/comments.pl?sid=29967&cid=3218526

Good stuff!