On Thu, 13 May 1999 22:52:04 -0400, Chris Maryan <cma### [at] geocitiescom>
wrote:
>
>What advantages does your approach offer over other methods?
>

It removes the ambient term totally.  This is the major advantage first and
foremost.  POVs radiosity still relies on that  ambient term even in its
radiosity calcs.  Try turning your ambient levels to 0.0 on all your surfaces.
Set two renders side by side, one with radiosity and the other without.   They
will look exactly the same.  There is a reason for this.  To get good
"radiosity effects" you have to have your ambient up around 0.2 and higher.
See why this is bad?      In order to get diffuse illumination in POV you must
add fake diffuse illumination first (the ambient term).   This is redundant.
Radiosity should figure this out on its own.  (I have this "funny" idea that's
what radiosity was for in the first place!   But no.... POV seems to be
fishing towards some sort of simulation of color bleeding, and not much else.
I can assure you that diffuse illumination, or global illumination is
potentially much more complicated than a simulation of color bleeding.)

1.  It's potentially slower than the current POV radiosity.   Also potentially
much, much faster.
2.  Unlike POV, it is essentially noiseless.  POVs radiosity suffers from
terrible artifacts, that only dissappear by smoothing out the results.   But
then you have smoothed out and fuzzy-looking results.   Mine is noiseless and
in sort of super-focus.
3.  POV can't really pull off a recursion level past level 1.  This one can do
as many as you like if you have the patience.
4.  Without a really obvious example scene, I can tell you that anything
clearly visible in a reflection in a POV scene des not have radiosity
calculated on it.   I'm sure this is a simple fix (maybe).  But nonetheless.
5.  This is not "regular radiosity" meaning this is NOT that form-factor
method where you subdivide all the surfaces into triangles.  For this reason,
any surface tracable with rays can be used in a scene with this new method
without a hitch.  i.e. this method is a _sampling method_ and not a quantizing
or deterministic method.  Just like POV.
6.  This method is not confused by a dozen or so tweaking parameters that are
obscure in meaning.
7.   I question whether or not this method uses more memory or not.  I have
had POV crash and run out of memory on mosaic passes when I told it to do a
radiosity sample on every single point.  My roomate noted that my HD was going
nuts all night long.    It may be the case that this method is more elegant
memory wise.  I hope to have all of its databases in quiet physical RAM the
whole time.    This is possible, the databases will run approx 8 megs  and
never more than 20.

Any other questions?

---------------------
Steve H.

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