Re: VisAD 3D surface graph performance

Hi Lezlie,

Something's wrong here. Lots of the test programs in the
visad/examples directory render surfaces with RGB mappings
that are much larger than 380 points, and much quicker than
a minute even on my old 500 MHz laptop with a bad old
graphics card. You might try running Test33, Test37 and
Test61 (its volume rendering is made of a series of flat
surfaces with a total of over 42000 points, and runs in a
few seconds on my laptop).

Bill

On Thu, 7 Apr 2005, Lezlie Fort wrote:

> Hello,
>
> I have a VisAD performance question.
>
> I've written recently before - indicating that I am creating a number of
> different graphs using ASCII space-separated input files.  One of the
> graph types that I'm generating is a "4D" surface graph.  Yesterday, I
> ran a case with the following math type:  (Time,Depth)->(Speed,col),
> where "col" is a fourth dimension that I have mapped to Display.RGB.
> The case that I ran had about 380 data points in  all four vectors, and
> I found that on my Linux box (nVidia GeForce FX graphics card, 1.5GHz
> processor, 512M RAM), it took about 1.5 minutes for the graph to
> generate.  On my Windows XP box (2.27 GHz processor, 512M RAM, Intel
> 82845G video board - Open GL version of Java3D), it took about 3.5
> minutes to generate.  I ran additional cases where I increased the data
> size, and ended up killing the graph-generation process after 5 minutes
> of intensive disk-chunking.  I know that 3D surface generation is very
> computation-intensive (3D line graphs of the same data come up almost
> instantly), but I was wondering if these performance numbers that I'm
> seeing are typical.  I've tried to find information on other graphing
> packages (eg:  MatLab) to determine what kind of performance one would
> expect with them, but seem to have encountered varied information.  Any
> ideas on whether what I'm seeing is typical, or is there perhaps
> something that I am doing extremely incorrectly?
>
> Thanks alot,
> lzf
>