POV-Ray : Newsgroups : povray.binaries.images : Desk lamp progress : Re: Desk lamp progress Server Time
5 Oct 2022 14:00:32 EDT (-0400)
  Re: Desk lamp progress  
From: Cousin Ricky
Date: 26 Aug 2022 21:05:29
Message: <63096dd9$1@news.povray.org>
On 2022-08-26 17:16 (-4), Dave Blandston wrote:
> 
> I'm guessing the extreme brightness is what's causing the lack of anti-aliasing
> around the front edge of the hood. Could the use of light_group be used to fix
> that?

I actually did use a light group in my original lamp 17 years ago, but
aliasing was not the issue.  I used large fade distances, which did not
illuminate the hood interior sufficiently to cause anti-aliasing
difficulties.

The problem I had back then was how to avoid a sharp cutoff of the
light, which is recessed, by the hood without requiring an area light.
The attached image shows this issue.  I solved it in 2005 by using a
non-recessed wide-angle spotlight to illuminate the scene, and a light
group to illuminate the hood interior.

I made the decision last year to abandon that approach.  There would be
a single light_source, centered on the light bulb, for both the hood
interior and the scene, with the spotlight being repurposed for
radiosity replacement.  But a light group would not have solved the
problem anyway; the issue is the light intensity that realistic
attenuation entails, and a light group doesn't change that.  I verified
this by rendering my original 2005-2006 lamp with input arguments that
forced realistic attenuation.

I would rather deal with hyper-white aliasing by post-processing.


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test_desklamp-v38d0r0.jpg


 

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