Why don't light_groups control the illumination of scattering media? Is
this a bug?

Abe

Post a reply to this message

In article <3BE72201.5E3C684B@taconic.net> , Abe <bul### [at] taconicnet>  
wrote:

> Why don't light_groups control the illumination of scattering media? Is
> this a bug?

Light groups influence light sources.  Read the media documentation to learn
about the difference between light sources and scattering media.

    Thorsten

Post a reply to this message

In article <3be79a97@news.povray.org>, tho### [at] trfde says...

> Light groups influence light sources. 

light_groups affect light_sources and light_sources affect scattering 
media. 

quote from the doc: "Note that some media effects depend upon light 
sources"

So light_groups SHOULD (indirectly) influence scattering media.

But they don't, I reported this a while ago, too.

example:
(both sheres _should_ be lit only by the green light_source)

#version 3.5;
camera
{
	location <0,0,-5>
}

light_source
{
	<1,1,-2>*10
	color rgb <1,0,0>
	media_interaction on
}


light_group
{
	light_source
	{
		<-1,-1,-2>*10
		color rgb <0,1,0>
		media_interaction on
	} 

	sphere
	{
		0,1 
		pigment{color rgb 1}
		translate x*1
	}
	
	sphere
	{
		0,1
		hollow
		pigment{color rgbt 1}
		interior{media{scattering {1,color rgb 10}}}
		translate -x*1
	}
}

Post a reply to this message

In article <MPG.16520f4740fa36bd9896b1@news.povray.org> , Lutz-Peter Hooge
<lpv### [at] gmxde>  wrote:

> example:
> (both sheres _should_ be lit only by the green light_source)

You are right, your example should show two greene spheres.  I misunderstood
the original posters problem ... which would have been clear with a sample
scene...

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org

Post a reply to this message