Re: animation question & NullPointerException

• To: Don Murray <dmurray@xxxxxxxxxxxxxxxx>
• Subject: Re: animation question & NullPointerException
• From: Bill Hibbard <billh@xxxxxxxxxxxxx>
• Date: Sat, 21 Feb 2004 12:57:39 -0600 (CST)

Just FYI, Curtis and I spoke about this and there is a
solution that will require Curtis to write a custom
DataRenderer. Basically, it would use a 'by reference'
form of Java3D texture, that would be used to update
texture contents without doing VisAD transforms. Some
form of this would probably be useful to a number of
applications. It won't happen soon, as he is busy with
other work right now.

Cheers,
Bill

On Sat, 21 Feb 2004, Don Murray wrote:

> Hi Curtis-
>
> Curtis Rueden wrote:
> > When animating, the process is typically smooth for a few frames,
> > followed by one choppy frame, then smooth again, etc. When studying
> > VisBio's memory monitor, I noticed that these choppy frames correspond
> > to Java garbage collection operations. That is, the memory usage creeps
> > up by about 20MB per frame, then drops back down to previous levels
> > during the choppy frame.
> >
> > My question is: can I fix this behavior, and if so, how? I realize that
> > this problem may be beyond the control of VisAD's display model, but I
> > thought I'd ask anyway to see if there are any thoughts or suggestions.
>
> When we were doing some performance analysis in VisAD last year,
> we found that a lot of the time was spent in garbage collection.
> VisAD allocates a lot of float[][] arrays during transformations
> and eventually, these have to get garbage collected.  Our
> (Jeff's) enhancements tried to minimize these as much as possible,
> but methods like adjustSeam() and adjustLongitude in VisADGeometryArray
> classes still allocate a lot of memory which then gets collected.
>
> I don't have any solutions, but thought I'd throw in my 2 cents.
>
> don
> *************************************************************
> Don Murray                               UCAR Unidata Program
> dmurray@xxxxxxxxxxxxxxxx                        P.O. Box 3000
> (303) 497-8628                              Boulder, CO 80307
> http://www.unidata.ucar.edu/staff/donm
> "There's someone in my head, but it's not me"    Roger Waters
> *************************************************************
>
>
>

• References:
  • Re: animation question & NullPointerException
    • From: Don Murray