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1 Aug 2024 16:29:16 EDT (-0400)
  forced perception. (Message 1 to 5 of 5)  
From: Barehunter
Subject: forced perception.
Date: 19 Sep 2005 00:20:01
Message: <web.432e3b9f5b656ae519a709290@news.povray.org>
Hi. I am doing a pic in which a photo of a mountain range is used as a
background. Trouble is with shadows. A large object throws a shadow on the
ground which is ok. However it is also throwing a shadow onto the
background mountain range. Is there some way to prevent the shadow from
hitting it while still remaining on the ground?


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From: Slime
Subject: Re: forced perception.
Date: 19 Sep 2005 00:45:50
Message: <432e427e$1@news.povray.org>
> Hi. I am doing a pic in which a photo of a mountain range is used as a
> background. Trouble is with shadows. A large object throws a shadow on the
> ground which is ok. However it is also throwing a shadow onto the
> background mountain range. Is there some way to prevent the shadow from
> hitting it while still remaining on the ground?

You can force an object to ignore light sources completely with

finish {diffuse 0 ambient 1}

If you want to alter the color of the image (to make it match the rest of
the scene's lighting, for instance), you can change "ambient 1" to "ambient
<r,g,b>", or just change the 1 to a lower value.

 - Slime
 [ http://www.slimeland.com/ ]


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From: Raf256
Subject: Re: forced perception.
Date: 19 Sep 2005 01:17:24
Message: <28u103-crb.ln1@raf256.com>
Barehunter <web.432e3b9f5b656ae519a709290@news.povray.org> Monday 19 of
September 2005 06:16

> Is there some way to prevent the shadow from
> hitting it while still remaining on the ground?

Perhaps using light groups

-- 


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From: Slime
Subject: Re: forced perception.
Date: 19 Sep 2005 03:11:47
Message: <432e64b3$1@news.povray.org>
> > Is there some way to prevent the shadow from
> > hitting it while still remaining on the ground?
>
> Perhaps using light groups


Sadly, there's no way to use light groups to prevent a shadow from falling
on an object. =(

A no_external_shadow keyword for light groups (affecting only light from the
light sources within the group) would be very convenient.

 - Slime
 [ http://www.slimeland.com/ ]


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From: gonzo
Subject: Re: forced perception.
Date: 24 Sep 2005 14:24:44
Message: <433599ec@news.povray.org>
Barehunter wrote:
> Hi. I am doing a pic in which a photo of a mountain range is used as a
> background. Trouble is with shadows. A large object throws a shadow on the
> ground which is ok. However it is also throwing a shadow onto the
> background mountain range. Is there some way to prevent the shadow from
> hitting it while still remaining on the ground?

As someone suggested, use ambient for the photo.  Other than that, 
re-scaling the photo larger and moving it further away...

RG


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