Here are two of my photon mapping experimens one using refractive caustics
and the other using reflective caustics.  The glass image uses reflective
caustics as well, but the contribution to the scene is minimal.

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Attachments:
Download 'Caustics.jpg' (111 KB) Download 'Reflect.jpg' (49 KB)

Preview of image 'Caustics.jpg'

Preview of image 'Reflect.jpg'

My first thought was to dive into that glass picture and roll around,
but considering how painful that would be I didn't. Beautiful to my
eyes, the both of them.
Have you tried out radiosity with this yet?


Shinzaho wrote:
> 
> Here are two of my photon mapping experimens one using refractive caustics
> and the other using reflective caustics.  The glass image uses reflective
> caustics as well, but the contribution to the scene is minimal.

-- 
 omniVERSE: beyond the universe
  http://members.aol.com/inversez/POVring.htm
 mailto:inv### [at] aolcom?PoV

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Great looking images!

It is really cool to see all of the creative ways that people are testing
this patch!!!!

For the reflections one, you probably will want a higher density of photons.
How many photons were used for that one, by the way.  It does look good the
way it is though... looks like an area light is being used.

Which reminds me, I never documented this:
The photon mapping patch currently treats all kinds of lights like point
lights.  This, of course, will eventually be changed.

But this brings up an interesting point... to simulate an area light, just
use a lower density of photons (doesn't always work).

The reflections pic also shows off one 'bug' with the patch.  You can see
some weird effects between the reflections of the F and L (see my ascii
art... the plus marks show where to look in the image for the artifacts,
which appear brighter than they should).

 ******  **
 ******  **
 **      **
 **      **
 ******  **
 ******  **
 **      **
 ** +++  **
 ** +++  ******
 ** +++  ******

In my final documentation, I'll explain why this happens.  But for now,
to fix this problem, you can either a) increase the density of the photons,
or b) use only one search radius:

if it was
  radius 0.1, 2, 0.1
change it to
  radius 0.2, 1

-Nathan

Shinzaho wrote:
> 
> Here are two of my photon mapping experimens one using refractive caustics
> and the other using reflective caustics.  The glass image uses reflective
> caustics as well, but the contribution to the scene is minimal.
> 
>  [Image]
> 
>  [Image]

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Bob Hughes <inv### [at] aolcom> wrote in article
<36ED2462.67A857D5@aol.com>...

> Have you tried out radiosity with this yet?

I didn't try it with the glass pic since I didn't think radiosity would
really contribute anything more to the scene.  However, I'll probably do a
re-rendering of the reflections pic with radiosity on.  It'd probably help
with the walls.

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Nathan Kopp <Nat### [at] Koppcom> wrote in article
<36ED338D.41DC804E@Kopp.com>...
> For the reflections one, you probably will want a higher density of
photons.
> How many photons were used for that one, by the way.  It does look good
the
> way it is though... looks like an area light is being used.

129,569 photons were used.  I tried rendering it with a higher density and
the little reflections being cast onto the far wall by the lettering
against the far wall disappeared, so I lowered the density again.

Michael

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Shinzaho wrote:
> 
> Bob Hughes <inv### [at] aolcom> wrote in article
> <36ED2462.67A857D5@aol.com>...
> 
> > Have you tried out radiosity with this yet?
> 
> I didn't try it with the glass pic since I didn't think radiosity would
> really contribute anything more to the scene.  However, I'll probably do a
> re-rendering of the reflections pic with radiosity on.  It'd probably help
> with the walls.
> 

  In the past few days I have tried using radiosty with glass and reflective
objects with very poor results. The radiosity settings I have used so far
made the use of the function wash out the scene with too much color
intereaction. Every object in the scene took on the characteristics of the
objects around them. If you come up with some useful settings that work I
would appreciate it if you would post them so I can see where I am going
wrong. I have a scene I am working on that has maybe half the number of
glass objects your scene has but they are much larger and brighter in
appearence.

Thanks,

-- 
Ken Tyler

mailto://tylereng@pacbell.net

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When I said 'higher density', I meant 'more photons' (meaning a lower
number for following the 'density' keyword).

If you go to higher density, also use a proportionately smaller gather
radius (maybe multiply both density and gather radius by 0.5).

130k photons is not that many when they contribute so much to the scene.

-Nathan

Shinzaho wrote:
> 
> Nathan Kopp <Nat### [at] Koppcom> wrote in article
> <36ED338D.41DC804E@Kopp.com>...
> > For the reflections one, you probably will want a higher density of
> photons.
> > How many photons were used for that one, by the way.  It does look good
> the
> > way it is though... looks like an area light is being used.
> 
> 129,569 photons were used.  I tried rendering it with a higher density and
> the little reflections being cast onto the far wall by the lettering
> against the far wall disappeared, so I lowered the density again.
> 
> Michael

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