Can media only be put in large containers?  Large with respect to one
POV unit.  Most examples I've seen have large spheres with media in
them.  Is there a way to scale down the media or containers?  Or do I
have to enlarge everything in my scene?

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In article <36F2D5BE.F86968D1@pilot.msu.edu>, portelli
<por### [at] pilotmsuedu> wrote:

>        Can media only be put in large containers?  Large with respect to one
>POV unit.  Most examples I've seen have large spheres with media in
>them.  Is there a way to scale down the media or containers?  Or do I
>have to enlarge everything in my scene?

You might end up having to increase the density above 1. Media effects are
not unit independent. So if you change the size of your media container,
you'll most likely need to change the density. If you make the object
bigger, reduce the density; if you make the object smaller, increase the
density.

I haven't worked with densities above 1, however, and have no idea what
that will do.

Jerry

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portelli wrote:
> 
>         Can media only be put in large containers?  Large with respect to one
> POV unit.  Most examples I've seen have large spheres with media in
> them.  Is there a way to scale down the media or containers?  Or do I
> have to enlarge everything in my scene?

Media have to be tuned to the size of the container in order to look
right.
Just as in real life, you might be able to see right through a glass of
murky water 
but couldn't see the bottom of a swimming pool full of the same water. 
So the 
density of the media must be adjusted for the effect you want.
You also have to scale any patterns to the overall scale of your scene.

Most important, Practice ;)

Cheers, PoD.

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How do you do this.  I looked in th edocs but it does not tell you
much.  Is there a float to put somewhere?  I tried before  the pattern
type but I get an error.

Jerry wrote:
> 
> In article <36F2D5BE.F86968D1@pilot.msu.edu>, portelli
> <por### [at] pilotmsuedu> wrote:
> 
> >        Can media only be put in large containers?  Large with respect to one
> >POV unit.  Most examples I've seen have large spheres with media in
> >them.  Is there a way to scale down the media or containers?  Or do I
> >have to enlarge everything in my scene?
> 
> You might end up having to increase the density above 1. Media effects are
> not unit independent. So if you change the size of your media container,
> you'll most likely need to change the density. If you make the object
> bigger, reduce the density; if you make the object smaller, increase the
> density.
> 
> I haven't worked with densities above 1, however, and have no idea what
> that will do.
> 
> Jerry

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It's basically a case of coupling scale in the media object with  the
density floats/vectors (and/or scattering {}).

 Container {
 //etc., etc.
   media {
 //blah, blah
     density { rgb <.1,.2,.3> } //increase if scale decreases
   }
  scale <.5,.5,.5> //decreased scale, reverse if scaling up
 }


portelli wrote:
> 
> How do you do this.  I looked in th edocs but it does not tell you
> much.  Is there a float to put somewhere?  I tried before  the pattern
> type but I get an error.
> 
> Jerry wrote:
> >
> > In article <36F2D5BE.F86968D1@pilot.msu.edu>, portelli
> > <por### [at] pilotmsuedu> wrote:
> >
> > >        Can media only be put in large containers?  Large with respect to one
> > >POV unit.  Most examples I've seen have large spheres with media in
> > >them.  Is there a way to scale down the media or containers?  Or do I
> > >have to enlarge everything in my scene?
> >
> > You might end up having to increase the density above 1. Media effects are
> > not unit independent. So if you change the size of your media container,
> > you'll most likely need to change the density. If you make the object
> > bigger, reduce the density; if you make the object smaller, increase the
> > density.
> >
> > I haven't worked with densities above 1, however, and have no idea what
> > that will do.
> >
> > Jerry

-- 
 omniVERSE: beyond the universe
  http://members.aol.com/inversez/homepage.htm
 mailto:inv### [at] aolcom?Subject=PoV-News

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I'm afraid I still don't understand.  Do you increase the color values? 
How would you make the pov example,( the fire in the sphere,
hollow3.pov) to a one unit sized sphere? 

Bob Hughes wrote:
> 
> It's basically a case of coupling scale in the media object with  the
> density floats/vectors (and/or scattering {}).
> 
>  Container {
>  //etc., etc.
>    media {
>  //blah, blah
>      density { rgb <.1,.2,.3> } //increase if scale decreases
>    }
>   scale <.5,.5,.5> //decreased scale, reverse if scaling up
>  }
> 
> portelli wrote:
> >
> > How do you do this.  I looked in th edocs but it does not tell you
> > much.  Is there a float to put somewhere?  I tried before  the pattern
> > type but I get an error.
> >
> > Jerry wrote:
> > >
> > > In article <36F2D5BE.F86968D1@pilot.msu.edu>, portelli
> > > <por### [at] pilotmsuedu> wrote:
> > >
> > > >        Can media only be put in large containers?  Large with respect to one
> > > >POV unit.  Most examples I've seen have large spheres with media in
> > > >them.  Is there a way to scale down the media or containers?  Or do I
> > > >have to enlarge everything in my scene?
> > >
> > > You might end up having to increase the density above 1. Media effects are
> > > not unit independent. So if you change the size of your media container,
> > > you'll most likely need to change the density. If you make the object
> > > bigger, reduce the density; if you make the object smaller, increase the
> > > density.
> > >
> > > I haven't worked with densities above 1, however, and have no idea what
> > > that will do.
> > >
> > > Jerry
> 
> --
>  omniVERSE: beyond the universe
>   http://members.aol.com/inversez/homepage.htm
>  mailto:inv### [at] aolcom?Subject=PoV-News

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You can do it two different ways.
Either increase 'emission' OR increase the density values by a factor
based upon the change in size.
I tried a 10 times reduction (scale 2.5 rather than 25) on the media
container object and raised the emission 10 times (0.5 rather than
0.05). This makes the same thing as the original.
Oh, and the camera location and look_at numbers were all brought down to
one tenth too (not angle 35, same for it) and also the translate 25*y
changed to 2.5*y to keep the view the same.
'density' can instead be raised 10 times and emission left alone. Skip
scattering altogether if at all possible.

So, it's rather simple. Just go higher or lower as much as you go up or
down in size scale.


portelli wrote:
> 
> I'm afraid I still don't understand.  Do you increase the color values?
> How would you make the pov example,( the fire in the sphere,
> hollow3.pov) to a one unit sized sphere?
> 
> Bob Hughes wrote:
> >
> > It's basically a case of coupling scale in the media object with  the
> > density floats/vectors (and/or scattering {}).
> >
> >  Container {
> >  //etc., etc.
> >    media {
> >  //blah, blah
> >      density { rgb <.1,.2,.3> } //increase if scale decreases
> >    }
> >   scale <.5,.5,.5> //decreased scale, reverse if scaling up
> >  }
> >
> > portelli wrote:
> > >
> > > How do you do this.  I looked in th edocs but it does not tell you
> > > much.  Is there a float to put somewhere?  I tried before  the pattern
> > > type but I get an error.
> > >
> > > Jerry wrote:
> > > >
> > > > In article <36F2D5BE.F86968D1@pilot.msu.edu>, portelli
> > > > <por### [at] pilotmsuedu> wrote:
> > > >
> > > > >        Can media only be put in large containers?  Large with respect to one
> > > > >POV unit.  Most examples I've seen have large spheres with media in
> > > > >them.  Is there a way to scale down the media or containers?  Or do I
> > > > >have to enlarge everything in my scene?
> > > >
> > > > You might end up having to increase the density above 1. Media effects are
> > > > not unit independent. So if you change the size of your media container,
> > > > you'll most likely need to change the density. If you make the object
> > > > bigger, reduce the density; if you make the object smaller, increase the
> > > > density.
> > > >
> > > > I haven't worked with densities above 1, however, and have no idea what
> > > > that will do.
> > > >
> > > > Jerry
> >
> > --
> >  omniVERSE: beyond the universe
> >   http://members.aol.com/inversez/homepage.htm
> >  mailto:inv### [at] aolcom?Subject=PoV-News

-- 
 omniVERSE: beyond the universe
  http://members.aol.com/inversez/homepage.htm
 mailto:inv### [at] aolcom?Subject=PoV-News

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Ya I got it thanks.  But now how do you get it so the media does not hit
the container.  I think I read this in the docs somewhere.  I'll have to
look again.

Bob Hughes wrote:
> 
> You can do it two different ways.
> Either increase 'emission' OR increase the density values by a factor
> based upon the change in size.
> I tried a 10 times reduction (scale 2.5 rather than 25) on the media
> container object and raised the emission 10 times (0.5 rather than
> 0.05). This makes the same thing as the original.
> Oh, and the camera location and look_at numbers were all brought down to
> one tenth too (not angle 35, same for it) and also the translate 25*y
> changed to 2.5*y to keep the view the same.
> 'density' can instead be raised 10 times and emission left alone. Skip
> scattering altogether if at all possible.
> 
> So, it's rather simple. Just go higher or lower as much as you go up or
> down in size scale.
> 
> portelli wrote:
> >
> > I'm afraid I still don't understand.  Do you increase the color values?
> > How would you make the pov example,( the fire in the sphere,
> > hollow3.pov) to a one unit sized sphere?
> >
> > Bob Hughes wrote:
> > >
> > > It's basically a case of coupling scale in the media object with  the
> > > density floats/vectors (and/or scattering {}).
> > >
> > >  Container {
> > >  //etc., etc.
> > >    media {
> > >  //blah, blah
> > >      density { rgb <.1,.2,.3> } //increase if scale decreases
> > >    }
> > >   scale <.5,.5,.5> //decreased scale, reverse if scaling up
> > >  }
> > >
> > > portelli wrote:
> > > >
> > > > How do you do this.  I looked in th edocs but it does not tell you
> > > > much.  Is there a float to put somewhere?  I tried before  the pattern
> > > > type but I get an error.
> > > >
> > > > Jerry wrote:
> > > > >
> > > > > In article <36F2D5BE.F86968D1@pilot.msu.edu>, portelli
> > > > > <por### [at] pilotmsuedu> wrote:
> > > > >
> > > > > >        Can media only be put in large containers?  Large with respect to
one
> > > > > >POV unit.  Most examples I've seen have large spheres with media in
> > > > > >them.  Is there a way to scale down the media or containers?  Or do I
> > > > > >have to enlarge everything in my scene?
> > > > >
> > > > > You might end up having to increase the density above 1. Media effects are
> > > > > not unit independent. So if you change the size of your media container,
> > > > > you'll most likely need to change the density. If you make the object
> > > > > bigger, reduce the density; if you make the object smaller, increase the
> > > > > density.
> > > > >
> > > > > I haven't worked with densities above 1, however, and have no idea what
> > > > > that will do.
> > > > >
> > > > > Jerry
> > >
> > > --
> > >  omniVERSE: beyond the universe
> > >   http://members.aol.com/inversez/homepage.htm
> > >  mailto:inv### [at] aolcom?Subject=PoV-News
> 
> --
>  omniVERSE: beyond the universe
>   http://members.aol.com/inversez/homepage.htm
>  mailto:inv### [at] aolcom?Subject=PoV-News

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Again, scaling it, adjusting...
If you use turbulence you may get a clipped media, especially noticeable
with spherical mapped media in a typical 1 POV unit sphere container and
the density ranging from none at 0 (outer edge) and full at 1 (center)
with turbulence 1 since the media then jumps around inside. As a general
rule you can either scale the media itself (or
density{density_map{}scale}) a bit smaller or perhaps add a secondary
media 'absorption' with frequency -1 based loosely upon the first;
however not as easy to get right.


portelli wrote:
> 
> Ya I got it thanks.  But now how do you get it so the media does not hit
> the container.  I think I read this in the docs somewhere.  I'll have to
> look again.

-- 
 omniVERSE: beyond the universe
  http://members.aol.com/inversez/homepage.htm
 mailto:inv### [at] aolcom?Subject=PoV-News

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