POV-Ray : Newsgroups : povray.general : Reflected sunlight falls on a material, over the year Server Time
29 Mar 2024 02:13:31 EDT (-0400)
  Reflected sunlight falls on a material, over the year (Message 11 to 13 of 13)  
<<< Previous 10 Messages Goto Initial 10 Messages
From: Tim Attwood
Subject: Re: Reflected sunlight falls on a material, over the year
Date: 15 Jan 2007 17:51:27
Message: <45ac056f$1@news.povray.org>
If you are interested in just the answer and not the
rendered animation you could place the camera at
your target object location, then point it at the mirror.
Then just place something like a torus in the sky
along the path of the sun with hash marks in the texture
so you can see where the sun will pass at what time.

Place the camera at both sides of your object, you
should only have to render this twice to get the
variation in when the shadow will start passing over
the object.


Post a reply to this message

From: chaps
Subject: Re: Reflected sunlight falls on a material, over the year
Date: 16 Jan 2007 15:55:00
Message: <web.45ad3b4faa573b971ecfa0090@news.povray.org>
Hello,

What i understand is that you want to know if the sun will hilight something
after  a reflection in a miror.

I suggest to use the property of light which say that a beam shoot in the
opposite direction will follow the same path (in reverse).

So you can evalute the direction of the sun with two angles (may sunpos can
help) and then place an orthograhic camera in that direction, which will
look at the mirror. All the objects that will be hit by the sun will be
visible in the mirror.

Pascal


Post a reply to this message

From: Philipp
Subject: Re: Reflected sunlight falls on a material, over the year
Date: 22 Feb 2007 12:00:00
Message: <web.45ddcacdaa573b97d749dd2a0@news.povray.org>
"chaps" <cha### [at] yahoocom> wrote:
> Hello,
>
> What i understand is that you want to know if the sun will hilight something
> after  a reflection in a miror.

Yes.

> I suggest to use the property of light which say that a beam shoot in the
> opposite direction will follow the same path (in reverse).

[...]

Hi Pascal,

that is certainly a good idea!

I am working now together with a friend, we finally decided to go and use
photon mapping, and it seems to work out great. It is the more intuitive
way somehow. The mirror reflects colored light, so we see very clearly
where the mirrored light goes.
Though, we did not simulate days and hours, but rather sun positions, which
we later translate into date/time ranges using a graph - that way we need
not do so many frames that would be very similar anyway.

Thank you all for your very helpful support!

Philipp


Post a reply to this message

<<< Previous 10 Messages Goto Initial 10 Messages

Copyright 2003-2023 Persistence of Vision Raytracer Pty. Ltd.