Announce: Tachyon 0.92 (parallel/multithreaded ray tracing)

Announce: Tachyon 0.92 (parallel/multithreaded ray tracing)

Post by John Sto » Fri, 24 Nov 2000 14:30:16



Tachyon version 0.92
--------------------
Tachyon is a multiprocessor ray tracing system which can be used as a
standalone program, or as a library within other programs.  It supports
almost any Unix-like system, Windows, MacOS-X and BeOS, as well as
several embedded systems and high end supercomputers.

Tachyon is written in C, uses POSIX threads and/or MPI for utilization
of multiple processors, and can also run on uniprocessor machines.
Tachyon is easy to port to new machines, and is fast, using ray tracing
acceleration schemes to achieve good performance on very complex scenes.
(It will handle scenes containing more than 100,000 objects on a fairly
 average computer)

Tachyon 0.92 adds new ports to Linux on Alpha processors, and
MacOS-X, as well as a new multithreaded Linux build with runtime
OpenGL display.  This version also includes a performance fix which
provides a 70% increase in speed when rendering very complex scenes
with large numbers of objects.  The new distribution also texture maps
for most of the example scenes, although they have been decimated to
lower resolution for practicality of distribution.  Pre-compiled
binaries are made available for 14 platforms.

The Tachyon home page is here:
  http://jedi.ks.uiuc.edu/~johns/raytracer/

Tachyon 0.92 can be downloaded from:
  http://jedi.ks.uiuc.edu/~johns/raytracer/files/0.92/

If you have questions of need any help, please send email to
the author: <johns at megapixel.com>

Thanks for your time,
  John Stone
  johns at megapixel.com

 
 
 

Announce: Tachyon 0.92 (parallel/multithreaded ray tracing)

Post by Warp » Fri, 24 Nov 2000 04:00:00


  Should I understand from the documentation that:

  - You can't transform the objects (with eg. a transformation matrix)?
  - You can't make copies of objects?
  - The amount of supersampling used for antialiasing will directly make
    the rendering time equally longer (that is, if I use 1 extra sample
    for antialiasing, the rendering will take twice the time, if I use 2
    extra samples, the rendering will take 3 times more, and so on)?

--
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):_;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

 
 
 

Announce: Tachyon 0.92 (parallel/multithreaded ray tracing)

Post by John Sto » Sat, 25 Nov 2000 14:03:52


Hi,

Quote:>  Should I understand from the documentation that:

>  - You can't transform the objects (with eg. a transformation matrix)?

That is correct.  The current version of the code (thus 0.92) does not
allow transformations, although this is easy to implement I have not  
had the time to do it yet.

Quote:>  - You can't make copies of objects?

Nope.  There is no high level scene graph, its as raw as OpenGL without
display lists or vertex arrays, but this will not always be the case,  
its just a present limitation.

Quote:>  - The amount of supersampling used for antialiasing will directly make
>    the rendering time equally longer (that is, if I use 1 extra sample
>    for antialiasing, the rendering will take twice the time, if I use 2
>    extra samples, the rendering will take 3 times more, and so on)?

Yup, this is currently the case, it uses a trivial algorithm for
supersampling.

However, it is very fast.  It doesn't compete with programs like
POV-Ray or Renderman, it will probably never have the sophisticated
shading/rendering capabilities that these programs have, but that's
ok, because Tachyon is tiny, and is fast, which makes it useful for
a lot of things that these and other programs are not able to do.  

POV-Ray for example, cannot render the 7381 sphere sphereflake scene
at a rate of 15-30 frames per second on a Cray T3E, Tachyon can.
Tachyon is way faster than most of the other programs for rendering
highly geometric scenes such as those found in molecular visualization,
it is much more aptly suited to this task than most renderers are.  It
provides most of the benefits of more complex, featureful,
(and slower) ray tracers, but is faster, simpler to use
(due to its lack of features) and  is fairly easy to modify if you're
interested in hacking it to do something it doesn't already do.

If you're looking for a program to beat POV-Ray and Renderman at their
own games, Tachyon isn't it, and probably never will be.  But, Tachyon
does do a lot of things that these programs cannot do.  

  John Stone
  johns at megapixel.com

 
 
 

Announce: Tachyon 0.92 (parallel/multithreaded ray tracing)

Post by Paul Bour » Sun, 26 Nov 2000 13:57:47


Quote:> If you're looking for a program to beat POV-Ray and Renderman at their
> own games, Tachyon isn't it, and probably never will be.  But, Tachyon
> does do a lot of things that these programs cannot do.  

Just picking up on this thread.....I agree totally, an area of interest
for me is a rendering package that is suited to visualisation applications
in scienec, mathematics, engineering, etc.

The desirable features would include

1. Ability to handle HUGE models, most likely polygonal. This is one of
   main drawbacks of things like Radiance and PovRay, although they do
   a lot better than any commercial application I've used. I have yet
   to throw a large model at Tachyon.

2. Ability to operate in a distributed environment, either SMP or on
   clusters. I have yet to compile Tachyon with MPI on our cluster.

P a u l   B o u r k e
Visualisation Research Fellow

http://www.swin.edu.au/astronomy/pbourke/

 
 
 

Announce: Tachyon 0.92 (parallel/multithreaded ray tracing)

Post by Chris Huf » Sun, 26 Nov 2000 04:00:00




> Tachyon is written in C, uses POSIX threads and/or MPI for utilization
> of multiple processors, and can also run on uniprocessor machines.
> Tachyon is easy to port to new machines, and is fast, using ray tracing
> acceleration schemes to achieve good performance on very complex scenes.
> (It will handle scenes containing more than 100,000 objects on a fairly
>  average computer)

> Tachyon 0.92 adds new ports to Linux on Alpha processors, and
> MacOS-X,

Whee!
Sounds too fast, though...need to add blurred reflection, radiosity,
photon mapping, differential ray-tracing, some more nicely processor
intensive volumetric media features... ;-)
Seriously, it looks like a good "lean-n-mean, multi-platform rendering
machine"...though the scene language is, well, undeveloped at this
stage. I'm interested where you intend to go with the language...just an
extremely basic description format, or a more advanced scripting
language?

Unfortunately, the Mac OS X binary didn't seem to survive...it shows up
as a text file that neither OpenUp nor Stuffit Expander know what to do
with. I was able to compile it on my own without too much trouble, but I
haven't figured out how to use it yet.

--
Christopher James Huff


<><

 
 
 

Announce: Tachyon 0.92 (parallel/multithreaded ray tracing)

Post by Warp » Tue, 28 Nov 2000 16:39:33


: 1. Ability to handle HUGE models, most likely polygonal. This is one of
:    main drawbacks of things like Radiance and PovRay

  What do you mean by "HUGE"?
  Is a scene with 100 million triangles "HUGE"?

--
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):_;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

 
 
 

1. ANNOUNCE(POV-Ray): Ray tracing of trimmed rational surfaces

 Hello,

  I would like to announce new unofficial version of POV-Ray 3.02. This version
extends latest POV-Ray by ability of ray tracing trimmed rational (bezier)
surface patches. In addition it renders current "bicubic_patch" nearly at same
speed as method from official POV-Ray 3.02 but it does not require big ammount
of precomputed data. You can download source code of this patch from:

     ftp://atrey.karlin.mff.cuni.cz/pub/local/0rfelyus/povray-3.02/

  There are also binaries for Linux and MS DOS(compiled with DJGPP v2). Please
send me your comments, advices or reminders. Also I would like to see beautiful
pictures which you render with this version.

Dan

ps: if you are interested in algorithm I use than look at: Tomoyuki Nishita,
Thomas W. Sederberg and Masanori Kakimoro: Ray Tracing Trimmed Ratinnal Surface
Patches [proceedengs of SIGGRAPH '90; Computer Graphics, vol 24, Num 4, August
1990]

2. Art Wanted for Digital Catalogue

3. Is there a BBS for Gateway 2000 Comp?

4. parallel ray tracing code

5. How to recover lost sculptures and textures in PSP6

6. Leveller 0.92 available, plus its web site

7. NEW, CHEAP AND GOOD SOFTWARES!

8. GUM 0.92

9. Announce: C++ ray tracing library homepage

10. ANNOUNCE: Ray Tracing News site upgrades

11. ANNOUNCE: Ray tracing mailing list