 |
|
|
|
|
|
| |
| |
|
|
|
|
| |
| |
|
|
I'm messing with media, trying to create a rocket exhaust plume. I'm
more or less a beginner when it comes to media stuff. I've been
moderately successful, however I'm having a problem:
#declare exhaust_half=
intersection {
sphere {
<0,0,0>,2
hollow
no_shadow
texture { pigment { rgbt 1 } }
interior {
media {
emission 0.9 method 3 intervals 10
density {
denT3
}
}
media {
absorption .2 method 3 intervals 10
density {
denT3
}
}
}
}
// Cut away negative y; doesn't do what I want:
cylinder {<0,0,0>,<0,1.01,0>,1000}
}
What I'm trying to get here is a media cloud that is not a complete
sphere but one half of a sphere. The problem is that if I look at this
from below (camera's y<0) the 'bottom' of the media cloud looks black,
as if it's opaque. It doesn't matter if I use intersection, difference
or clipped_by. How can I get a media cloud that is not a complete sphere
but only for example the part of the sphere with y>0 ?
--
Bjorn Jonsson / bjj### [at] ZZZmmedia is
Address changed to avoid spam. Remove YYY and
ZZZ to reply.
Post a reply to this message
|
|
| |
| |
|
|
From: "Jérôme M. Berger"
Subject: Re: Media and clipped_by, intersection and difference
Date: 21 Feb 2004 19:37:10
Message: <4037f9b6$1@news.povray.org>
|
|
|
| |
| |
|
|
Two things:
+ I believe your cylinder should read:
"cylinder {<0,0,0>,<0,2.01,0>,1000}"
+ Youshould first do the intersection, then apply the texture { pigment
rgbt 1 } } and the interior with the media to the whole object instead
of just the sphere.
Jerome
Bjorn Jonsson wrote:
> I'm messing with media, trying to create a rocket exhaust plume. I'm
> more or less a beginner when it comes to media stuff. I've been
> moderately successful, however I'm having a problem:
>
> #declare exhaust_half=
> intersection {
> sphere {
> <0,0,0>,2
> hollow
> no_shadow
> texture { pigment { rgbt 1 } }
> interior {
> media {
> emission 0.9 method 3 intervals 10
> density {
> denT3
> }
> }
> media {
> absorption .2 method 3 intervals 10
> density {
> denT3
> }
> }
> }
> }
> // Cut away negative y; doesn't do what I want:
> cylinder {<0,0,0>,<0,1.01,0>,1000}
> }
>
> What I'm trying to get here is a media cloud that is not a complete
> sphere but one half of a sphere. The problem is that if I look at this
> from below (camera's y<0) the 'bottom' of the media cloud looks black,
> as if it's opaque. It doesn't matter if I use intersection, difference
> or clipped_by. How can I get a media cloud that is not a complete sphere
> but only for example the part of the sphere with y>0 ?
>
Post a reply to this message
|
|
| |
| |
|
|
From: Hughes, B
Subject: Re: Media and clipped_by, intersection and difference
Date: 21 Feb 2004 19:59:21
Message: <4037fee9$1@news.povray.org>
|
|
|
| |
| |
|
|
news:4037f9b6$1@news.povray.org...
> Two things:
> + I believe your cylinder should read:
> "cylinder {<0,0,0>,<0,2.01,0>,1000}"
Or possibly cylinder {0,2*y,2} ?
> + You should first do the intersection, then apply the texture { pigment
> rgbt 1 } } and the interior with the media to the whole object instead
> of just the sphere.
Common mistake, that, leaving textures out of parts of a CSG and thinking
they'll automatically inherit a parent one.
Bob H.
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
In article <MPG.1aa206d25403ff9989691@news.povray.org>,
Bjorn Jonsson <bjj### [at] mmediais> wrote:
> What I'm trying to get here is a media cloud that is not a complete
> sphere but one half of a sphere. The problem is that if I look at this
> from below (camera's y<0) the 'bottom' of the media cloud looks black,
> as if it's opaque.
That's because it *is* black and opaque. You have:
intersection {
sphere {<0,0,0>, 2
texture { pigment { rgbt 1 } }
interior {...}
}
cylinder {<0,0,0>,<0,1.01,0>,1000}
}
That's an intersection of a sphere with a clear texture and a cylinder
with the default texture, which happens to be black and opaque. You want
to apply the texture and interior to the intersection, not to just one
of its parts:
intersection {
sphere {<0,0,0>, 2}
cylinder {<0,0,0>,<0,1.01,0>,1000}
texture { pigment { rgbt 1 } }
interior {...}
}
> It doesn't matter if I use intersection, difference
> or clipped_by. How can I get a media cloud that is not a complete sphere
> but only for example the part of the sphere with y>0 ?
Well, you shouldn't use clipped_by, because the media starts and stops
at the surface of the shape, and clipped_by leaves gaps in the surface.
CSG difference and intersection will work fine, once you get them
textured right.
--
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
In article <4037fee9$1@news.povray.org>,
"Hughes, B." <omn### [at] charternet> wrote:
> Common mistake, that, leaving textures out of parts of a CSG and thinking
> they'll automatically inherit a parent one.
Children *will* inherit a parent's texture. The problem here is that
only one child is textured.
--
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/
Post a reply to this message
|
|
| |
| |
|
|
From: Hughes, B
Subject: Re: Media and clipped_by, intersection and difference
Date: 22 Feb 2004 00:38:53
Message: <4038406d$1@news.povray.org>
|
|
|
| |
| |
|
|
"Christopher James Huff" <cja### [at] earthlinknet> wrote in message
news:cjameshuff-7D545B.20224121022004@news.povray.org...
> In article <4037fee9$1@news.povray.org>,
> "Hughes, B." <omn### [at] charternet> wrote:
>
> > Common mistake, that, leaving textures out of parts of a CSG and
thinking
> > they'll automatically inherit a parent one.
>
> Children *will* inherit a parent's texture. The problem here is that
> only one child is textured.
Sorry, I worded that wrong. By parent I meant the object within the CSG
statement, and first thing I think of is difference {} using the first items
texture, thus making a sort of dominant one among the rest. My bad thinking
processes just confusing matters there. Esp. since this was about a
intersection instead.
Bob H.
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
In article <4038406d$1@news.povray.org>,
"Hughes, B." <omn### [at] charternet> wrote:
> Sorry, I worded that wrong. By parent I meant the object within the CSG
> statement,
But that's a child of the CSG. Look in the source. ;-)
> and first thing I think of is difference {} using the first items
> texture, thus making a sort of dominant one among the rest. My bad thinking
> processes just confusing matters there. Esp. since this was about a
> intersection instead.
A difference doesn't work any differently...the texture of th first
object is the texture of those parts of the difference that come from
that object.
--
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Thanks for the replies. Doing the intersection before applying the media
stuff solved all of my problems (also I'm now intersecting with a plane
instead of cylinder). However, I'm only moderately happy with the result
(I'm doing a semi-transparent rocket exhaust plume) since this is my
first 'serious' use of media. Does anyone know of a nice media tutorial
? Needless to say I have looked at the POV documentation but I'm looking
for something more detailed with examples.
--
Bjorn Jonsson / bjj### [at] ZZZmmediais
Address changed to avoid spam. Remove YYY and
ZZZ to reply.
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
|
|
