POV-Ray : Newsgroups : povray.binaries.images : Glass for v3.8 finish features : Re: Glass for v3.8 finish features Server Time
2 Dec 2022 12:11:57 EST (-0500)
  Re: Glass for v3.8 finish features  
From: Thomas de Groot
Date: 10 Aug 2022 02:04:55
Message: <62f34a87$1@news.povray.org>
Op 09/08/2022 om 19:09 schreef MichaelJF:
> Am 09.08.2022 um 17:16 schrieb William F Pokorny:
>> On 8/9/22 10:50, Thomas de Groot wrote:
>>> Op 9-8-2022 om 14:53 schreef Thomas de Groot:
>>>> initially, I wanted to concentrate on the hdr light sources though...
>>>>
>>> ...and when I do, no photons are generated!
>>>
>>> I use
>>>    photons {
>>>      refraction on
>>>      reflection on
>>>    }
>>>
>>> for the sphere with the hdr map, identical to the code for the light 
>>> source. Decreasing spacing down to a ridiculously small value doesn't 
>>> change anything. I must be missing something here...
>>>
>>
>> I'm perhaps not following, but...
>>
>> Taking your hdr sphere to be an actual hollow sphere, you are making 
>> it a photon target for any photon light sources by adding the photon 
>> block above. In other words - as far as I know - there is no way to 
>> shoot photons from other than a traditional light sources.
>>
>> Aside: I've never tried to shoot photons from a light source inside a 
>> hollow object at the inside surface of that object. I'm not sure it 
>> would work given the how the radial 'shooting pattern' is aimed at 
>> target objects. Perhaps this the reason why you get no photons? Hmm, 
>> maybe a spot light would work... Too long since I've played with photons.
>>
>> Bill P.
> Unfortunatelly, Bill seems to be right. I tried a bit, but it seems to 
> be impossible to persuade a HDRI light to cast photons, so we need POV 
> 4.0 ;)
> 

That was also the conclusion I reached.

POV 4.0, where are you? :-)

-- 
Thomas


Post a reply to this message

Copyright 2003-2021 Persistence of Vision Raytracer Pty. Ltd.