POV-Ray : Newsgroups : povray.advanced-users : BoxCubeEnvironment Mapping Server Time
3 Jul 2024 06:23:04 EDT (-0400)
  BoxCubeEnvironment Mapping (Message 1 to 3 of 3)  
From: Woody
Subject: BoxCubeEnvironment Mapping
Date: 30 Apr 2008 13:30:00
Message: <web.4818ac948fad940b94e61a50@news.povray.org>
How does one go about creating a Box\Cube\Environment Mapping. I realize I may
be asking a very general question, but is there a specific method? I notice
there isn't anything similar that can be used in the image_map keyword.

Let's say I wanted the outside world reflected onto a cube made out of a mirror
material? What about the same, except for a sphere?

-Jeff


Post a reply to this message

From: Alain
Subject: Re: BoxCubeEnvironment Mapping
Date: 30 Apr 2008 14:03:45
Message: <4818b481$1@news.povray.org>
Woody nous illumina en ce 2008/04/30 13:29 -->
> How does one go about creating a Box\Cube\Environment Mapping. I realize I may
> be asking a very general question, but is there a specific method? I notice
> there isn't anything similar that can be used in the image_map keyword.
> 
> Let's say I wanted the outside world reflected onto a cube made out of a mirror
> material? What about the same, except for a sphere?
> 
> -Jeff
> 
> 
There is no such thing as "environment mapping" in a ray tracer.
What you can do is to make a large box or sphere placed around your scene. Then 
you apply a texture to that object with an image_map. Usualy an acceptable 
solution for background and far away scene elements.
For closer elements, you construct them like the rest of the scene. No object 
need to be in the camera's field of view.

If you need a sky, you can use the sky_sphere background feature. Good to 
simulate a stary sky of a slightly cloudy sky when the cloud cover is to light 
to actualy cast shadows on the ground.
Any ground plane will get reflected by a reflective surface.
For quick cloude you can use a transparent plane or large sphere with some 
pattern to simulate clouds. If you stack several such surfaces in an union and 
use the same pattern, like bumps, it can give some volume to the clouds. Be sure 
to increase max_trace_level in that case to at lease 2 more than the number of 
surfaces used.

-- 
Alain
-------------------------------------------------
"If you see me running, try to keep up."
       ...Back of bomb technician's shirt


Post a reply to this message

From: Chris B
Subject: Re: BoxCubeEnvironment Mapping
Date: 30 Apr 2008 14:31:59
Message: <4818bb1f@news.povray.org>
"Woody" <nomail@nomail> wrote in message 
news:web.4818ac948fad940b94e61a50@news.povray.org...
> How does one go about creating a Box\Cube\Environment Mapping. I realize I 
> may
> be asking a very general question, but is there a specific method? I 
> notice
> there isn't anything similar that can be used in the image_map keyword.
>
> Let's say I wanted the outside world reflected onto a cube made out of a 
> mirror
> material? What about the same, except for a sphere?
>
> -Jeff
>


Hi Jeff,

You should be able to use uv_mapping to map an image_map to a box.

If you want a reflective object mirroring the environment you can use a 
finish of 'reflection 1'. You can use the sky_sphere with an image_map to 
display an image around the scene to provide something to reflect.

If you don't want to see the original image you can use a big sphere in 
place of a sky_sphere with the no_image object modifier which will give you 
the reflection without the image itself. If using a sphere in this way 
you'll need to scale up the pigment containing the image_map.

Regards,
Chris B.


Post a reply to this message

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