POV-Ray : Newsgroups : povray.general : Recommendations on creating a spotlight with a visible cone Server Time
28 Mar 2024 04:40:51 EDT (-0400)
  Recommendations on creating a spotlight with a visible cone (Message 1 to 6 of 6)  
From: Steve Anger
Subject: Recommendations on creating a spotlight with a visible cone
Date: 26 Aug 2019 16:50:06
Message: <web.5d64459be0212fbb8bed1fa0@news.povray.org>
Any suggestions on how to create a spotlight with a visible cone that fades at
the edges without using media? I've tried using a spotlight inside a cone object
with a scattering media applied to the cone. The effect is not bad but the media
is affected by all light sources in the scene, not just the spotlight spoiling
much of the effect. I also get random bright pixels at the edges of the cone.

I'm wondering is there is a simpler way to fake the effect.


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From: Bald Eagle
Subject: Re: Recommendations on creating a spotlight with a visible cone
Date: 27 Aug 2019 07:20:00
Message: <web.5d6510e9fc99bc204eec112d0@news.povray.org>
"Steve Anger" <nomail@nomail> wrote:
> Any suggestions on how to create a spotlight with a visible cone that fades at
> the edges without using media? I've tried using a spotlight inside a cone object
> with a scattering media applied to the cone. The effect is not bad but the media
> is affected by all light sources in the scene, not just the spotlight spoiling
> much of the effect. I also get random bright pixels at the edges of the cone.
>
> I'm wondering is there is a simpler way to fake the effect.

light groups

http://wiki.povray.org/content/Reference:Light_Group


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From: Steve Anger
Subject: Re: Recommendations on creating a spotlight with a visible cone
Date: 27 Aug 2019 22:40:01
Message: <web.5d65e95efc99bc208bed1fa0@news.povray.org>
"Bald Eagle" <cre### [at] netscapenet> wrote:
> "Steve Anger" <nomail@nomail> wrote:
> > Any suggestions on how to create a spotlight with a visible cone that fades at
> > the edges without using media? I've tried using a spotlight inside a cone object
> > with a scattering media applied to the cone. The effect is not bad but the media
> > is affected by all light sources in the scene, not just the spotlight spoiling
> > much of the effect. I also get random bright pixels at the edges of the cone.
> >
> > I'm wondering is there is a simpler way to fake the effect.
>
> light groups
>
> http://wiki.povray.org/content/Reference:Light_Group

That worked great. Thanks! There seems to be a bug in the media code that
produced random bright pixels when reflective objects are used. The reflections
were not that important to the scene so I removed them.

It's been "many" years since I've worked with POV-Ray. I'm enjoying discovering
all the new features.


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From: Bald Eagle
Subject: Re: Recommendations on creating a spotlight with a visible cone
Date: 28 Aug 2019 17:55:00
Message: <web.5d66f7a6fc99bc204eec112d0@news.povray.org>
"Steve Anger" <nomail@nomail> wrote:

> That worked great. Thanks! There seems to be a bug in the media code that
> produced random bright pixels when reflective objects are used. The reflections
> were not that important to the scene so I removed them.

Well, it's media, which can be pretty complex to implement, and harder to debug.
Could be a bug, could be just one of those things....
But glad to hear that was just what you needed.

> It's been "many" years since I've worked with POV-Ray. I'm enjoying discovering
> all the new features.

Yeah - it's taken me a while to work through it all, and honestly, there's SO
much, that you just have to keep cycling through it all, otherwise you just
forget that there's even Feature X or Macro Y or Include file Z....

Friedrich Lohmueller [RIP] and Mike Williams' website are staples in my
reference collections, as are the drop-down Insert menu.

Hope your scenes are working out and giving you good results   :)

- Bill


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From: Thomas de Groot
Subject: Re: Recommendations on creating a spotlight with a visible cone
Date: 29 Aug 2019 02:18:03
Message: <5d676e1b$1@news.povray.org>
Op 28/08/2019 om 23:52 schreef Bald Eagle:
> 
> "Steve Anger" <nomail@nomail> wrote:
> 
>> That worked great. Thanks! There seems to be a bug in the media code that
>> produced random bright pixels when reflective objects are used. The reflections
>> were not that important to the scene so I removed them.
> 
> Well, it's media, which can be pretty complex to implement, and harder to debug.
> Could be a bug, could be just one of those things....
> But glad to hear that was just what you needed.

I have been pondering this issue. Might be too few samples in the media. 
Try increasing them. Also, it might be worthwhile to experiment with 
UberPov in this particular case.

> 
>> It's been "many" years since I've worked with POV-Ray. I'm enjoying discovering
>> all the new features.
> 
> Yeah - it's taken me a while to work through it all, and honestly, there's SO
> much, that you just have to keep cycling through it all, otherwise you just
> forget that there's even Feature X or Macro Y or Include file Z....
> 
> Friedrich Lohmueller [RIP] and Mike Williams' website are staples in my
> reference collections, as are the drop-down Insert menu.
> 
> Hope your scenes are working out and giving you good results   :)
> 
> - Bill
> 

seconded.

-- 
Thomas


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From: Steve Anger
Subject: Re: Recommendations on creating a spotlight with a visible cone
Date: 19 Sep 2019 01:25:00
Message: <web.5d831035fc99bc208bed1fa0@news.povray.org>
Thomas de Groot <tho### [at] degrootorg> wrote:
> > Well, it's media, which can be pretty complex to implement, and harder to debug.
> > Could be a bug, could be just one of those things....
> > But glad to hear that was just what you needed.
>
> I have been pondering this issue. Might be too few samples in the media.
> Try increasing them. Also, it might be worthwhile to experiment with
> UberPov in this particular case.

I downloaded the latest experimental version and all the media artifacts have
disappeared.


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