 |
|
|
|
|
|
| |
| |
|
|
From: Alain
Subject: Re: I Need Help With Media (small sample image)
Date: 16 May 2004 09:25:54
Message: <40a76be2@news.povray.org>
|
|
|
| |
| |
|
|
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type">
<title></title>
</head>
<body vlink="#551a8b" alink="#ee0000" link="#0000ee" text="#330000"
bgcolor="#cccccc">
Danny nous apporta ses lumieres ainsi en ce 2004/05/15 17:26... : <br>
<blockquote cite="midweb.40a68af75c9adbfeffb015460@news.povray.org"
type="cite">
<pre wrap="">I'm trying to create a cylindrical laser that's white in the center,
fades
to red, and then fades to nothing at the edges so that it has a fuzzy
boundary. I know I need to use media, but I don't know what any of the
media terms do, so could anybody tell me which of them could help me?
</pre>
</blockquote>
Use a cylindrical pattern for your media enclosed in a long containing
cylinder. Then, assign it a color_map, 1 for the center, 0 for the
edge. It could look like this:<br>
///////////////////////////////////////////////<br>
cylinder{0,1,<0,1000,0>,1 texture{pigment{rgbt 1}}//invisible
enclosing shape<br>
interior{<br>
media {emission rgb 1 //make it an emissive,
luminous media<br>
density{ cylindrical<br>
color_map{[0 rgb 0][0.5 rgb<1,0,0>][0.98
rgb 1][1 rgb 2]}<br>
// Nothing outside, fade to pure red at mid point then to white then
double bright white at the very center<br>
}<br>
}<br>
}<br>
hollow // VERY IMPORTENT, if not present, the media
will disapears<br>
rotate<anglex,angley,anglez>// to orient your "beam" any way
you like<br>
translate<x,y,z> // to place it exactly where you want it to
go.<br>
}<br>
///////////////////////////////////////////////<br>
By having one end of the shape at 0 make it easier to correctly orient
and place it, it rotate around that point.<br>
It should looks best using ratiosity, as it will effectively emit light.<br>
<img height="90" width="144" alt=""
src="cid:par### [at] qwerty gov"><br>
Alain<br>
</body>
</html>
Post a reply to this message
Attachments:
Download 'test.jpg' (2 KB)
Preview of image 'test.jpg'
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Alain <aze### [at] qwertygov> wrote:
> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
> <html>
> <head>
> <meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type">
> <title></title>
> </head>
> <body vlink="#551a8b" alink="#ee0000" link="#0000ee" text="#330000"
> bgcolor="#cccccc">
> Danny nous apporta ses lumieres ainsi en ce 2004/05/15 17:26... : <br>
> <blockquote cite="midweb.40a68af75c9adbfeffb015460@news.povray.org"
> type="cite">
> <pre wrap="">I'm trying to create a cylindrical laser that's white in the center,
fades
> to red, and then fades to nothing at the edges so that it has a fuzzy
> boundary. I know I need to use media, but I don't know what any of the
> media terms do, so could anybody tell me which of them could help me?
>
> </pre>
> </blockquote>
> Use a cylindrical pattern for your media enclosed in a long containing
> cylinder. Then, assign it a color_map, 1 for the center, 0 for the
> edge. It could look like this:<br>
> ///////////////////////////////////////////////<br>
> cylinder{0,1,<0,1000,0>,1 texture{pigment{rgbt 1}}//invisible
> enclosing shape<br>
> interior{<br>
> media {emission rgb 1 //make it an emissive,
luminous media<br>
>
density{ cylindrical<br>
>
color_map{[0 rgb 0][0.5 rgb<1,0,0>][0.98
> rgb 1][1 rgb 2]}<br>
> // Nothing outside, fade to pure red at mid point then to white then
> double bright white at the very center<br>
> }<br>
> }<br>
> }<br>
> hollow // VERY IMPORTENT, if not present, the media
will disapears<br>
> rotate<anglex,angley,anglez>// to orient your "beam" any
way
> you like<br>
> translate<x,y,z> // to place it exactly where you want it
to
> go.<br>
> }<br>
> ///////////////////////////////////////////////<br>
> By having one end of the shape at 0 make it easier to correctly orient
> and place it, it rotate around that point.<br>
> It should looks best using ratiosity, as it will effectively emit light.<br>
> <img height="90" width="144" alt=""
> src="cid:par### [at] qwertygov"><br>
> Alain<br>
> </body>
> </html>
I used exactly what you told me, and I got a cylinder with white edges that
fades to nothing in the middle (without any red at all), and even those
white edges disappear as the cylinder continues on. I'm using POV-Ray 3.5,
and here is the code I used:
cylinder{<100,0,0>,<0,0,0>, .20
texture {
pigment { color rgbt 1}
finish{reflection 0}}
interior{media{emission rgb 1
density{ cylindrical
color_map{[0 rgb 0][0.5 rgb<1,0,0>][0.98 rgb 1][1 rgb 2]}
}}}
hollow
translate<0,0,2>
}
Can you tell me what I'm doing wrong, and how to fix it?
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Danny nous apporta ses lumieres ainsi en ce 2004/05/17 05:23... :
>Alain <aze### [at] qwertygov> wrote:
>
>
>
>I used exactly what you told me, and I got a cylinder with white edges that
>fades to nothing in the middle (without any red at all), and even those
>white edges disappear as the cylinder continues on. I'm using POV-Ray 3.5,
>and here is the code I used:
>
>cylinder{<100,0,0>,<0,0,0>, .20
> texture {
> pigment { color rgbt 1}
> finish{reflection 0}}
> interior{media{emission rgb 1
> density{ cylindrical
> color_map{[0 rgb 0][0.5 rgb<1,0,0>][0.98 rgb 1][1 rgb 2]}
> }}}
> hollow
> translate<0,0,2>
> }
>
>Can you tell me what I'm doing wrong, and how to fix it?
>
>
>
Set the radius of the cylinder to 1, then rescale it by scale<.2,1,.2>
just before you rotate it.
You don't need to set finish{reflection 0}}, it's the default value.
Set your cylinder verticaly, as it's the orientation of the cylindrical
pattern, then rotate the whole thing.
...
scale<0.2, 1, 0.2>
rotate -90*z
translate<0, 0, 2>
}
Alain
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Alain <aze### [at] qwertygov> wrote:
> Danny nous apporta ses lumieres ainsi en ce 2004/05/17 05:23... :
>
> >Alain <aze### [at] qwertygov> wrote:
> >
> >
> >
> >I used exactly what you told me, and I got a cylinder with white edges that
> >fades to nothing in the middle (without any red at all), and even those
> >white edges disappear as the cylinder continues on. I'm using POV-Ray 3.5,
> >and here is the code I used:
> >
> >cylinder{<100,0,0>,<0,0,0>, .20
> > texture {
> > pigment { color rgbt 1}
> > finish{reflection 0}}
> > interior{media{emission rgb 1
> > density{ cylindrical
> > color_map{[0 rgb 0][0.5 rgb<1,0,0>][0.98 rgb 1][1 rgb 2]}
> > }}}
> > hollow
> > translate<0,0,2>
> > }
> >
> >Can you tell me what I'm doing wrong, and how to fix it?
> >
> >
> >
> Set the radius of the cylinder to 1, then rescale it by scale<.2,1,.2>
> just before you rotate it.
> You don't need to set finish{reflection 0}}, it's the default value.
> Set your cylinder verticaly, as it's the orientation of the cylindrical
> pattern, then rotate the whole thing.
> ...
> scale<0.2, 1, 0.2>
> rotate -90*z
> translate<0, 0, 2>
> }
>
> Alain
OK, now it looks good when I don't scale it, but scaling it seems to mess it
up.
When I scale it up it still seems to look OK, except the inner white part
has become enlarged disproportionately. But when I scale it down, I lose
the white part completely, and all I have is a very dimly red cylinder.
Can you explain why it's doing this and how I can make it scale down right?
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Danny nous apporta ses lumieres ainsi en ce 2004/05/17 16:39... :
>Alain <aze### [at] qwertygov> wrote:
>
>
>>Danny nous apporta ses lumieres ainsi en ce 2004/05/17 05:23... :
>>
>>
>>
>>>Alain <aze### [at] qwertygov> wrote:
>>>
>>>
>>>
>>>I used exactly what you told me, and I got a cylinder with white edges that
>>>fades to nothing in the middle (without any red at all), and even those
>>>white edges disappear as the cylinder continues on. I'm using POV-Ray 3.5,
>>>and here is the code I used:
>>>
>>>cylinder{<100,0,0>,<0,0,0>, .20
>>> texture {
>>> pigment { color rgbt 1}
>>> finish{reflection 0}}
>>> interior{media{emission rgb 1
>>> density{ cylindrical
>>> color_map{[0 rgb 0][0.5 rgb<1,0,0>][0.98 rgb 1][1 rgb 2]}
>>> }}}
>>> hollow
>>> translate<0,0,2>
>>> }
>>>
>>>Can you tell me what I'm doing wrong, and how to fix it?
>>>
>>>
>>>
>>>
>>>
>>Set the radius of the cylinder to 1, then rescale it by scale<.2,1,.2>
>>just before you rotate it.
>>You don't need to set finish{reflection 0}}, it's the default value.
>>Set your cylinder verticaly, as it's the orientation of the cylindrical
>>pattern, then rotate the whole thing.
>>...
>>scale<0.2, 1, 0.2>
>>rotate -90*z
>>translate<0, 0, 2>
>>}// that's the last brace
>>
>>Alain
>>
>>
>
>OK, now it looks good when I don't scale it, but scaling it seems to mess it
>up.
>When I scale it up it still seems to look OK, except the inner white part
>has become enlarged disproportionately. But when I scale it down, I lose
>the white part completely, and all I have is a very dimly red cylinder.
>Can you explain why it's doing this and how I can make it scale down right?
>
>
>
Try lowering the 0.98 to a smaler value, thus enlarging the central
part. As it is now, the white center part only have a radius of 0.02
units and may disappears when scaled down or if the image is generated
at a low resolution.
Don't scale only the media but the whole cylinder containing the media.
Alain
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Alain <aze### [at] qwertygov> wrote:
> Danny nous apporta ses lumieres ainsi en ce 2004/05/17 16:39... :
>
> >Alain <aze### [at] qwertygov> wrote:
> >
> >
> >>Danny nous apporta ses lumieres ainsi en ce 2004/05/17 05:23... :
> >>
> >>
> >>
> >>>Alain <aze### [at] qwertygov> wrote:
> >>>
> >>>
> >>>
> >>>I used exactly what you told me, and I got a cylinder with white edges that
> >>>fades to nothing in the middle (without any red at all), and even those
> >>>white edges disappear as the cylinder continues on. I'm using POV-Ray 3.5,
> >>>and here is the code I used:
> >>>
> >>>cylinder{<100,0,0>,<0,0,0>, .20
> >>> texture {
> >>> pigment { color rgbt 1}
> >>> finish{reflection 0}}
> >>> interior{media{emission rgb 1
> >>> density{ cylindrical
> >>> color_map{[0 rgb 0][0.5 rgb<1,0,0>][0.98 rgb 1][1 rgb 2]}
> >>> }}}
> >>> hollow
> >>> translate<0,0,2>
> >>> }
> >>>
> >>>Can you tell me what I'm doing wrong, and how to fix it?
> >>>
> >>>
> >>>
> >>>
> >>>
> >>Set the radius of the cylinder to 1, then rescale it by scale<.2,1,.2>
> >>just before you rotate it.
> >>You don't need to set finish{reflection 0}}, it's the default value.
> >>Set your cylinder verticaly, as it's the orientation of the cylindrical
> >>pattern, then rotate the whole thing.
> >>...
> >>scale<0.2, 1, 0.2>
> >>rotate -90*z
> >>translate<0, 0, 2>
> >>}// that's the last brace
> >>
> >>Alain
> >>
> >>
> >
> >OK, now it looks good when I don't scale it, but scaling it seems to mess it
> >up.
> >When I scale it up it still seems to look OK, except the inner white part
> >has become enlarged disproportionately. But when I scale it down, I lose
> >the white part completely, and all I have is a very dimly red cylinder.
> >Can you explain why it's doing this and how I can make it scale down right?
> >
> >
> >
> Try lowering the 0.98 to a smaler value, thus enlarging the central
> part. As it is now, the white center part only have a radius of 0.02
> units and may disappears when scaled down or if the image is generated
> at a low resolution.
> Don't scale only the media but the whole cylinder containing the media.
>
> Alain
Thanks a lot for all your help! I managed to fix the scaling problem by
multiplying the brightness of all the color map values by 5. I guess this
is because there is less matter in the media to show up if I scale it down
to a fifth of its size.
Thanks,
Danny
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
"Danny" <danzaetz> wrote:
> Alain <aze### [at] qwertygov> wrote:
> > Danny nous apporta ses lumieres ainsi en ce 2004/05/17 16:39... :
> >
> > >Alain <aze### [at] qwertygov> wrote:
> > >
> > >
> > >>Danny nous apporta ses lumieres ainsi en ce 2004/05/17 05:23... :
> > >>
> > >>
> > >>
> > >>>Alain <aze### [at] qwertygov> wrote:
> > >>>
> > >>>
> > >>>
> > >>>I used exactly what you told me, and I got a cylinder with white edges that
> > >>>fades to nothing in the middle (without any red at all), and even those
> > >>>white edges disappear as the cylinder continues on. I'm using POV-Ray 3.5,
> > >>>and here is the code I used:
> > >>>
> > >>>cylinder{<100,0,0>,<0,0,0>, .20
> > >>> texture {
> > >>> pigment { color rgbt 1}
> > >>> finish{reflection 0}}
> > >>> interior{media{emission rgb 1
> > >>> density{ cylindrical
> > >>> color_map{[0 rgb 0][0.5 rgb<1,0,0>][0.98 rgb 1][1 rgb 2]}
> > >>> }}}
> > >>> hollow
> > >>> translate<0,0,2>
> > >>> }
> > >>>
> > >>>Can you tell me what I'm doing wrong, and how to fix it?
> > >>>
> > >>>
> > >>>
> > >>>
> > >>>
> > >>Set the radius of the cylinder to 1, then rescale it by scale<.2,1,.2>
> > >>just before you rotate it.
> > >>You don't need to set finish{reflection 0}}, it's the default value.
> > >>Set your cylinder verticaly, as it's the orientation of the cylindrical
> > >>pattern, then rotate the whole thing.
> > >>...
> > >>scale<0.2, 1, 0.2>
> > >>rotate -90*z
> > >>translate<0, 0, 2>
> > >>}// that's the last brace
> > >>
> > >>Alain
> > >>
> > >>
> > >
> > >OK, now it looks good when I don't scale it, but scaling it seems to mess it
> > >up.
> > >When I scale it up it still seems to look OK, except the inner white part
> > >has become enlarged disproportionately. But when I scale it down, I lose
> > >the white part completely, and all I have is a very dimly red cylinder.
> > >Can you explain why it's doing this and how I can make it scale down right?
> > >
> > >
> > >
> > Try lowering the 0.98 to a smaler value, thus enlarging the central
> > part. As it is now, the white center part only have a radius of 0.02
> > units and may disappears when scaled down or if the image is generated
> > at a low resolution.
> > Don't scale only the media but the whole cylinder containing the media.
> >
> > Alain
>
> Thanks a lot for all your help! I managed to fix the scaling problem by
> multiplying the brightness of all the color map values by 5. I guess this
> is because there is less matter in the media to show up if I scale it down
> to a fifth of its size.
> Thanks,
> Danny
I've got another problem. For some strange reason, my media cylinder is
acting like a convex lens. It's showing an narrowed image on the right side
of the cylinder of an object behind and to the left of it. It's refracting
(not reflecting) light, I think. When I zoom out, it looks like ugly white
lines on the side of my laser. How do I get rid of them?
Danny
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Danny nous apporta ses lumieres ainsi en ce 2004/05/18 15:08... :
>"Danny" <danzaetz> wrote:
>
>
>>Alain <aze### [at] qwertygov> wrote:
>>
>>
>>>Danny nous apporta ses lumieres ainsi en ce 2004/05/17 16:39... :
>>>
>>>
>>>
>>>>Alain <aze### [at] qwertygov> wrote:
>>>>
>>>>
>>>>
>>>>
>>>>>Danny nous apporta ses lumieres ainsi en ce 2004/05/17 05:23... :
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>Alain <aze### [at] qwertygov> wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>>I used exactly what you told me, and I got a cylinder with white edges that
>>>>>>fades to nothing in the middle (without any red at all), and even those
>>>>>>white edges disappear as the cylinder continues on. I'm using POV-Ray 3.5,
>>>>>>and here is the code I used:
>>>>>>
>>>>>>cylinder{<100,0,0>,<0,0,0>, .20
>>>>>> texture {
>>>>>> pigment { color rgbt 1}
>>>>>> finish{reflection 0}}
>>>>>> interior{media{emission rgb 1
>>>>>> density{ cylindrical
>>>>>> color_map{[0 rgb 0][0.5 rgb<1,0,0>][0.98 rgb 1][1 rgb 2]}
>>>>>> }}}
>>>>>> hollow
>>>>>> translate<0,0,2>
>>>>>> }
>>>>>>
>>>>>>Can you tell me what I'm doing wrong, and how to fix it?
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>Set the radius of the cylinder to 1, then rescale it by scale<.2,1,.2>
>>>>>just before you rotate it.
>>>>>You don't need to set finish{reflection 0}}, it's the default value.
>>>>>Set your cylinder verticaly, as it's the orientation of the cylindrical
>>>>>pattern, then rotate the whole thing.
>>>>>...
>>>>>scale<0.2, 1, 0.2>
>>>>>rotate -90*z
>>>>>translate<0, 0, 2>
>>>>>}// that's the last brace
>>>>>
>>>>>Alain
>>>>>
>>>>>
>>>>>
>>>>>
>>>>OK, now it looks good when I don't scale it, but scaling it seems to mess it
>>>>up.
>>>>When I scale it up it still seems to look OK, except the inner white part
>>>>has become enlarged disproportionately. But when I scale it down, I lose
>>>>the white part completely, and all I have is a very dimly red cylinder.
>>>>Can you explain why it's doing this and how I can make it scale down right?
>>>>
>>>>
>>>>
>>>>
>>>>
>>>Try lowering the 0.98 to a smaler value, thus enlarging the central
>>>part. As it is now, the white center part only have a radius of 0.02
>>>units and may disappears when scaled down or if the image is generated
>>>at a low resolution.
>>>Don't scale only the media but the whole cylinder containing the media.
>>>
>>>Alain
>>>
>>>
>>Thanks a lot for all your help! I managed to fix the scaling problem by
>>multiplying the brightness of all the color map values by 5. I guess this
>>is because there is less matter in the media to show up if I scale it down
>>to a fifth of its size.
>>
>>
Good guess
>>Thanks,
>>Danny
>>
>>
>
>I've got another problem. For some strange reason, my media cylinder is
>acting like a convex lens. It's showing an narrowed image on the right side
>of the cylinder of an object behind and to the left of it. It's refracting
>(not reflecting) light, I think. When I zoom out, it looks like ugly white
>lines on the side of my laser. How do I get rid of them?
>
>Danny
>
>
>
With emissive only media, the beam is effectively transparent, that is,
you see anything that may be behind. That was (barely) visible in the
small sample as a slight discontuity near the middle of the image. You
may want to add some absorbtion and/or scattering, it's not realistic as
the beam is only light, but may be more aestetic.
Alain
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Alain <aze### [at] qwertygov> wrote:
> Danny nous apporta ses lumieres ainsi en ce 2004/05/18 15:08... :
>
> >"Danny" <danzaetz> wrote:
> >
> >
> >>Alain <aze### [at] qwertygov> wrote:
> >>
> >>
> >>>Danny nous apporta ses lumieres ainsi en ce 2004/05/17 16:39... :
> >>>
> >>>
> >>>
> >>>>Alain <aze### [at] qwertygov> wrote:
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>>Danny nous apporta ses lumieres ainsi en ce 2004/05/17 05:23... :
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>>Alain <aze### [at] qwertygov> wrote:
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>I used exactly what you told me, and I got a cylinder with white edges that
> >>>>>>fades to nothing in the middle (without any red at all), and even those
> >>>>>>white edges disappear as the cylinder continues on. I'm using POV-Ray 3.5,
> >>>>>>and here is the code I used:
> >>>>>>
> >>>>>>cylinder{<100,0,0>,<0,0,0>, .20
> >>>>>> texture {
> >>>>>> pigment { color rgbt 1}
> >>>>>> finish{reflection 0}}
> >>>>>> interior{media{emission rgb 1
> >>>>>> density{ cylindrical
> >>>>>> color_map{[0 rgb 0][0.5 rgb<1,0,0>][0.98 rgb 1][1 rgb 2]}
> >>>>>> }}}
> >>>>>> hollow
> >>>>>> translate<0,0,2>
> >>>>>> }
> >>>>>>
> >>>>>>Can you tell me what I'm doing wrong, and how to fix it?
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>Set the radius of the cylinder to 1, then rescale it by scale<.2,1,.2>
> >>>>>just before you rotate it.
> >>>>>You don't need to set finish{reflection 0}}, it's the default value.
> >>>>>Set your cylinder verticaly, as it's the orientation of the cylindrical
> >>>>>pattern, then rotate the whole thing.
> >>>>>...
> >>>>>scale<0.2, 1, 0.2>
> >>>>>rotate -90*z
> >>>>>translate<0, 0, 2>
> >>>>>}// that's the last brace
> >>>>>
> >>>>>Alain
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>OK, now it looks good when I don't scale it, but scaling it seems to mess it
> >>>>up.
> >>>>When I scale it up it still seems to look OK, except the inner white part
> >>>>has become enlarged disproportionately. But when I scale it down, I lose
> >>>>the white part completely, and all I have is a very dimly red cylinder.
> >>>>Can you explain why it's doing this and how I can make it scale down right?
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>Try lowering the 0.98 to a smaler value, thus enlarging the central
> >>>part. As it is now, the white center part only have a radius of 0.02
> >>>units and may disappears when scaled down or if the image is generated
> >>>at a low resolution.
> >>>Don't scale only the media but the whole cylinder containing the media.
> >>>
> >>>Alain
> >>>
> >>>
> >>Thanks a lot for all your help! I managed to fix the scaling problem by
> >>multiplying the brightness of all the color map values by 5. I guess this
> >>is because there is less matter in the media to show up if I scale it down
> >>to a fifth of its size.
> >>
> >>
> Good guess
>
> >>Thanks,
> >>Danny
> >>
> >>
> >
> >I've got another problem. For some strange reason, my media cylinder is
> >acting like a convex lens. It's showing an narrowed image on the right side
> >of the cylinder of an object behind and to the left of it. It's refracting
> >(not reflecting) light, I think. When I zoom out, it looks like ugly white
> >lines on the side of my laser. How do I get rid of them?
> >
> >Danny
> >
> >
> >
> With emissive only media, the beam is effectively transparent, that is,
> you see anything that may be behind. That was (barely) visible in the
> small sample as a slight discontuity near the middle of the image. You
> may want to add some absorbtion and/or scattering, it's not realistic as
> the beam is only light, but may be more aestetic.
>
> Alain
Neither the absorption nor any of the scatterings are able to get rid of the
image. It's odd. It's not like the stars I have in the distance, which
are right behind the the laser and are completely visible through the
laser. The object is not directly behind the laser, it's back and to the
left, and not obstructed by the laser at all, but it's projecting a thinned
and flipped image of itself on the right side of the laser. Have you seen
anything like this?
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
"Danny" <danzaetz> wrote:
> Alain <aze### [at] qwertygov> wrote:
> > Danny nous apporta ses lumieres ainsi en ce 2004/05/18 15:08... :
> >
> > >"Danny" <danzaetz> wrote:
> > >
> > >
> > >>Alain <aze### [at] qwertygov> wrote:
> > >>
> > >>
> > >>>Danny nous apporta ses lumieres ainsi en ce 2004/05/17 16:39... :
> > >>>
> > >>>
> > >>>
> > >>>>Alain <aze### [at] qwertygov> wrote:
> > >>>>
> > >>>>
> > >>>>
> > >>>>
> > >>>>>Danny nous apporta ses lumieres ainsi en ce 2004/05/17 05:23... :
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>>>Alain <aze### [at] qwertygov> wrote:
> > >>>>>>
> > >>>>>>
> > >>>>>>
> > >>>>>>I used exactly what you told me, and I got a cylinder with white edges that
> > >>>>>>fades to nothing in the middle (without any red at all), and even those
> > >>>>>>white edges disappear as the cylinder continues on. I'm using POV-Ray 3.5,
> > >>>>>>and here is the code I used:
> > >>>>>>
> > >>>>>>cylinder{<100,0,0>,<0,0,0>, .20
> > >>>>>> texture {
> > >>>>>> pigment { color rgbt 1}
> > >>>>>> finish{reflection 0}}
> > >>>>>> interior{media{emission rgb 1
> > >>>>>> density{ cylindrical
> > >>>>>> color_map{[0 rgb 0][0.5 rgb<1,0,0>][0.98 rgb 1][1 rgb 2]}
> > >>>>>> }}}
> > >>>>>> hollow
> > >>>>>> translate<0,0,2>
> > >>>>>> }
> > >>>>>>
> > >>>>>>Can you tell me what I'm doing wrong, and how to fix it?
> > >>>>>>
> > >>>>>>
> > >>>>>>
> > >>>>>>
> > >>>>>>
> > >>>>>>
> > >>>>>>
> > >>>>>Set the radius of the cylinder to 1, then rescale it by scale<.2,1,.2>
> > >>>>>just before you rotate it.
> > >>>>>You don't need to set finish{reflection 0}}, it's the default value.
> > >>>>>Set your cylinder verticaly, as it's the orientation of the cylindrical
> > >>>>>pattern, then rotate the whole thing.
> > >>>>>...
> > >>>>>scale<0.2, 1, 0.2>
> > >>>>>rotate -90*z
> > >>>>>translate<0, 0, 2>
> > >>>>>}// that's the last brace
> > >>>>>
> > >>>>>Alain
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>OK, now it looks good when I don't scale it, but scaling it seems to mess it
> > >>>>up.
> > >>>>When I scale it up it still seems to look OK, except the inner white part
> > >>>>has become enlarged disproportionately. But when I scale it down, I lose
> > >>>>the white part completely, and all I have is a very dimly red cylinder.
> > >>>>Can you explain why it's doing this and how I can make it scale down right?
> > >>>>
> > >>>>
> > >>>>
> > >>>>
> > >>>>
> > >>>Try lowering the 0.98 to a smaler value, thus enlarging the central
> > >>>part. As it is now, the white center part only have a radius of 0.02
> > >>>units and may disappears when scaled down or if the image is generated
> > >>>at a low resolution.
> > >>>Don't scale only the media but the whole cylinder containing the media.
> > >>>
> > >>>Alain
> > >>>
> > >>>
> > >>Thanks a lot for all your help! I managed to fix the scaling problem by
> > >>multiplying the brightness of all the color map values by 5. I guess this
> > >>is because there is less matter in the media to show up if I scale it down
> > >>to a fifth of its size.
> > >>
> > >>
> > Good guess
> >
> > >>Thanks,
> > >>Danny
> > >>
> > >>
> > >
> > >I've got another problem. For some strange reason, my media cylinder is
> > >acting like a convex lens. It's showing an narrowed image on the right side
> > >of the cylinder of an object behind and to the left of it. It's refracting
> > >(not reflecting) light, I think. When I zoom out, it looks like ugly white
> > >lines on the side of my laser. How do I get rid of them?
> > >
> > >Danny
> > >
> > >
> > >
> > With emissive only media, the beam is effectively transparent, that is,
> > you see anything that may be behind. That was (barely) visible in the
> > small sample as a slight discontuity near the middle of the image. You
> > may want to add some absorbtion and/or scattering, it's not realistic as
> > the beam is only light, but may be more aestetic.
> >
> > Alain
>
> Neither the absorption nor any of the scatterings are able to get rid of the
> image. It's odd. It's not like the stars I have in the distance, which
> are right behind the the laser and are completely visible through the
> laser. The object is not directly behind the laser, it's back and to the
> left, and not obstructed by the laser at all, but it's projecting a thinned
> and flipped image of itself on the right side of the laser. Have you seen
> anything like this?
I still can't figure out how to get rid of the images on the surface of the
laser. Please help.
Danny
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
|
|
