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23 Dec 2024 22:37:49 EST (-0500)
  Lamps in a dark environment (Message 1 to 3 of 3)  
From: Justus von Sonntag
Subject: Lamps in a dark environment
Date: 9 Mar 2003 08:51:38
Message: <3e6b46ea$1@news.povray.org>
Hello, out there...

I am rather new to ray-tracing (spent only a few hundred hours on it, most
of it actually reading documentation) and still essentially on my first
topic - a ship in the ocean.

The light sources are the sky_sphere (blue -> black) and the position lights
of the vessel. They are modelled by a white light source within a cylinder
which sectors are painted red/green/white according to the rules of
sailorship.

While I am already quite satisfied with the effect of this light source on
the ship and the water (after introducing fade), the position lamp itself is
pretty dark - i.e. it does not shine.

Setting finish ambient to red/green/white did not help. Neither did so far
my experiments with looks_like

So here is my question: How do I make the lamp appear bright ? Any answers
are highly welcomed

--
Justus von Sonntag, Leipzig, Germany


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From: hughes, b 
Subject: Re: Lamps in a dark environment
Date: 9 Mar 2003 15:05:32
Message: <3e6b9e8c@news.povray.org>
"Justus von Sonntag" <Jus### [at] vonSonntagde> wrote in message
news:3e6b46ea$1@news.povray.org...
>
> The light sources are the sky_sphere (blue -> black) and the position
lights
> of the vessel. They are modelled by a white light source within a cylinder
> which sectors are painted red/green/white according to the rules of
> sailorship.
>
> While I am already quite satisfied with the effect of this light source on
> the ship and the water (after introducing fade), the position lamp itself
is
> pretty dark - i.e. it does not shine.
>
> Setting finish ambient to red/green/white did not help. Neither did so far
> my experiments with looks_like
>
> So here is my question: How do I make the lamp appear bright ? Any answers
> are highly welcomed

What you probably hadn't tried is to use less filtering on the colors of the
light object, still using the high ambient too. It's necessary to make the
object visible to get the ambience to show or else it just gets darker when
more invisible. The light will still shine through but you might need to
increase it's brightness to counteract the less transparent surface. If you
use it as a looks_like in the light_source it will be not cast a shadow, so
that might be unwanted; unless you are using only a pigmented object within
an opaque housing.

You can also add a finish {phong 1 phong_size 0 metallic} so that there is
colored hightlighting on its surface, in which case the filter value could
remain higher (more transparent, filter 1.0 is okay then) and not have to
increase the lights color value. This is actually probably the best
solution.

Bob


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From: Justus von Sonntag
Subject: Re: Lamps in a dark environment
Date: 11 Mar 2003 16:22:21
Message: <3e6e538d@news.povray.org>
Thanks, Bob,

that was just I was looking for. At least by combining both (low filter (say
0.1) and finish {phong etc.} I get a nice bright lamp.

Someday I might even understand what phong actually means - but now I have
to leave - some money got to be earned (how else does one get faster FPUs?)

cheers, Justus

"hughes, b." <omn### [at] charternet> wrote in
news:3e6b9e8c@news.povray.org...
> > So here is my question: How do I make the lamp appear bright ? Any
answers
> > are highly welcomed
>
> What you probably hadn't tried is to use less filtering on the colors of
the
> light object, still using the high ambient too. It's necessary to make the
> object visible to get the ambience to show or else it just gets darker
when
> more invisible. The light will still shine through but you might need to
> increase it's brightness to counteract the less transparent surface. If
you
> use it as a looks_like in the light_source it will be not cast a shadow,
so
> that might be unwanted; unless you are using only a pigmented object
within
> an opaque housing.
>
> You can also add a finish {phong 1 phong_size 0 metallic} so that there is
> colored hightlighting on its surface, in which case the filter value could
> remain higher (more transparent, filter 1.0 is okay then) and not have to
> increase the lights color value. This is actually probably the best
> solution.


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