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From: Thomas Willhalm
Subject: Re: Scientific use of povray
Date: 9 Sep 1998 04:25:29
Message: <qqmg1e1wxw6.fsf@goldach.fmi.uni-konstanz.de>
Tim Glover <tgl### [at] nettallycom> writes:
>
> I've recently used POVRay to visualize a groundwater flow problem --
> even created an animation of a fly-around.  Very impressive tools.  And
> .FLC seems so much superior to .avi or .mpg for color fidelity. 
> 
> Results are not not on the net right now. Sorry....  Anyone else doing
> this kind of thing?

We participated in the contest A at the "Sixth Symposium on Graph Drawing"
in Montreal this year (http://gd98.cs.mcgill.ca/). We submitted an animation 
that was rendered with POV-Ray -- and now share the first place with the 
group from Tuebingen (also in Germany). We converted the single files to FLI, 
AVI, and MPG. In my opinion the FLI is the nicest one. However, the file 
size of the MPG is much smaller (and still 60 MB).

Thomas

-- 
http://www.fmi.uni-konstanz.de/~willhalm


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From: Mathias Bachmann
Subject: Re: Scientific use of povray
Date: 9 Sep 1998 10:20:28
Message: <35f6809c.0@news.povray.org>
Jim Kress schrieb in Nachricht <35f57bcd.0@news.povray.org>...
>I'm sorry for the difficulty with the URL. Using outlook express is a real
>pain to send URLs.  I've tried typing them into the text, sending them as
>attachments, etc.  It seems no matter what I try, somebody can't get it to
>work.
>
>Anybody got a reliable solution to this?  I'd love to know one.
>
>You could start at http://www.kressworks.com/Research/Quantum
>Chemistry/Unimolecular Decomposition Reactions/  and then click on the N,N
>diethyl link.
>
>Please let me know if THIS works!
>
>Thanks.
>
>Jim

It's completely uncommon to have whitespaces in WWW-adresses, so try to
avoid that!
If you do, please mention that when you type an adress in e-mails, so people
can copy a string as
"http://www.kressworks.com/Research/Quantum Chemistry/Unimolecular
Decomposition Reactions/"
right into the Browser-window.
But at last, you _should_ replace your web-adresses with names that don't
contain whitespaces. use - (minus) or _ (underscore) instead!

And then, no, Outlook doesn't (normaly) have any problems with URLS in the
text. I think, when it does have problems, any other e-mail program will
have, too. Just be conform to internet-standards (which means here: DONT USE
WHITESPACES).

greetings,
Mathias


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From: Tim Glover
Subject: Re: Scientific use of povray
Date: 9 Sep 1998 16:09:30
Message: <35F6D22C.626@nettally.com>
Congrats on your first place!  I agree .mpg files are smaller (in my
case about 1.5 mbytes vs. 4.5 mbytes) but the colors were dithered
(poorly so, if I may add) and the overall effect was disappointing. 
FLI/FLC (with the free Autodesk viewer, no less!) preserves the color
scheme adequately w/o dithering - and looks good even in full screen
640X480 format.

I guess, like .jpg, you get only the quality out that you're willing to
pay for with file size.  
 
Tim G.

tgl### [at] nettallycom


Thomas Willhalm wrote:
> 
> Tim Glover <tgl### [at] nettallycom> writes:
> >
> > I've recently used POVRay to visualize a groundwater flow problem --
> > even created an animation of a fly-around.  Very impressive tools.  And
> > .FLC seems so much superior to .avi or .mpg for color fidelity.
> >
> > Results are not not on the net right now. Sorry....  Anyone else doing
> > this kind of thing?
> 
> We participated in the contest A at the "Sixth Symposium on Graph Drawing"
> in Montreal this year (http://gd98.cs.mcgill.ca/). We submitted an animation
> that was rendered with POV-Ray -- and now share the first place with the
> group from Tuebingen (also in Germany). We converted the single files to FLI,
> AVI, and MPG. In my opinion the FLI is the nicest one. However, the file
> size of the MPG is much smaller (and still 60 MB).
> 
> Thomas
> 
> --
> http://www.fmi.uni-konstanz.de/~willhalm


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From: Jim Kress
Subject: Re: Scientific use of povray
Date: 9 Sep 1998 21:05:08
Message: <35f717b4.0@news.povray.org>
Thanks for the info!

The white spaces come from the long file name capability in Win NT and Win
95/98.  Since, for local access on my Intranet I have had no problems with
these URLs, I didn't realize that over the Internet URL standards were not
kept up to date with evolving operating systems.

I'll have to decide if the (large!) amount of re-work on my site will have
to be done in light of this URL limitation.


Jim


<large SNIP! - just for you, Johannes :) >

>
>It's completely uncommon to have whitespaces in WWW-adresses, so try to
>avoid that!
>If you do, please mention that when you type an adress in e-mails, so
people
>can copy a string as
>"http://www.kressworks.com/Research/Quantum Chemistry/Unimolecular
>Decomposition Reactions/"
>right into the Browser-window.
>But at last, you _should_ replace your web-adresses with names that don't
>contain whitespaces. use - (minus) or _ (underscore) instead!
>
>And then, no, Outlook doesn't (normaly) have any problems with URLS in the
>text. I think, when it does have problems, any other e-mail program will
>have, too. Just be conform to internet-standards (which means here: DONT
USE
>WHITESPACES).
>
>greetings,
>Mathias
>
>


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From: Thomas Willhalm
Subject: Re: Scientific use of povray
Date: 10 Sep 1998 03:05:02
Message: <qqmbtoocxki.fsf@goldach.fmi.uni-konstanz.de>
Tim Glover <tgl### [at] nettallycom> writes:

> Congrats on your first place!  

Thanks a lot.

> I agree .mpg files are smaller (in my
> case about 1.5 mbytes vs. 4.5 mbytes) but the colors were dithered
> (poorly so, if I may add) and the overall effect was disappointing. 
> FLI/FLC (with the free Autodesk viewer, no less!) preserves the color
> scheme adequately w/o dithering - and looks good even in full screen
> 640X480 format.

Since we're using a Unix system, xanim and mpeg_play are our choice.
As far as I know mpegs are true color animations. The distortion that
you are referring to is due to the compression algorithm.

> I guess, like .jpg, you get only the quality out that you're willing to
> pay for with file size.  

Unfortunately, we will have to pay the prize, because 200 MB is really to
much for a web page in these days.

Thomas

-- 
http://www.fmi.uni-konstanz.de/~willhalm


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From: Nieminen Mika
Subject: Re: Scientific use of povray
Date: 10 Sep 1998 13:02:26
Message: <35f7f812.0@news.povray.org>
Jim Kress <jim### [at] dccmailcom> wrote:
: I didn't realize that over the Internet URL standards were not
: kept up to date with evolving operating systems.

  UNIX has had long filenames (with spaces, lower/uppercase letters, etc)
decades before NT was born.
  NT maybe evolving, but it's decades late in almost everything.

-- 
                                                           - Warp. -


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From: Abdulaziz Ghuloum
Subject: Re: Scientific use of povray
Date: 10 Sep 1998 14:53:07
Message: <35f81203.0@news.povray.org>
Nieminen Mika <war### [at] assaricctutfi> wrote in message
35f7f812.0@news.povray.org...
>Jim Kress <jim### [at] dccmailcom> wrote:
>: I didn't realize that over the Internet URL standards were not
>: kept up to date with evolving operating systems.
>
>  UNIX has had long filenames (with spaces, lower/uppercase letters, etc)
>decades before NT was born.
>  NT maybe evolving, but it's decades late in almost everything.

If I may add:  These standards were made to avoid compatibility problems
(such as the one we're talking about) and to promote platform-independence.
    Not all operating systems support white-spaces in their filesystems.
Plus, white-space is usually used as a delimiter.  For example: say you have
a program that accepts multiple URLs from the command prompt:
        getpages http://www.yahoo.com/ http://www.povray.org/
http://www.irtc.org/
How would one be able to use such a program if one of these URLs contained a
white-space?
    Anyways, HTTP Servers should conform to the standards, not the other way
around.  I, personally, would neven bother installing a web server that is
not HTTP compliant.

    Aziz,,,


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From: Johannes Hubert
Subject: Re: Scientific use of povray
Date: 11 Sep 1998 03:56:28
Message: <35f8c99c.0@news.povray.org>
Abdulaziz Ghuloum wrote in message <35f81203.0@news.povray.org>...
>How would one be able to use such a program if one of these URLs contained
a
>white-space?
>    Anyways, HTTP Servers should conform to the standards, not the other
way
>around.  I, personally, would neven bother installing a web server that is
>not HTTP compliant.


Actually, URL *can* contain whitespace: The official MIME format called
"x-www-form-urlencoded" allows for *all* characters, which are encoded like
this:
The alphanumerics stay as they are, space is converted to "+" and everything
else is converted to "%xx", where "xx" is the ascii-value of the character
in two-digit hex-code.
So an URL with a space would simply look like this for example:
http://www.example.com/url+with+whitespace.html
Even the http://www.example.com/url%20with%20whitespace.html version should
work, since I would not expect an URL decoder to not allow "%20" simply
because it *should* be coded with "+" instead.

So the problem could actually not be the server, but the browser, who
doesn't convert the URL to the MIME format...

Bye,
Johannes.


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From: Mathias Bachmann
Subject: Re: Scientific use of povray
Date: 14 Sep 1998 13:07:50
Message: <35fd3f56.0@news.povray.org>
>Congrats on your first place!  I agree .mpg files are smaller (in my
>case about 1.5 mbytes vs. 4.5 mbytes) but the colors were dithered
>(poorly so, if I may add) and the overall effect was disappointing.
>FLI/FLC (with the free Autodesk viewer, no less!) preserves the color
>scheme adequately w/o dithering - and looks good even in full screen
>640X480 format.


hm...
Sounds as if you are viewing the mpegs on an old 256 color display?
The dithering is due to your mpeg-display-software/hardware, not due to the
mpeg-file itself.
Mpegs are ALWAYS true-color. if your display/software doesnt find true-color
capabilities, it will dither down the video to 256 color in real-time. This
will result in poor quality. FLICS are ALWAYS only 256 colors. Colors are
dithered down at creation time (compile time?). When there is enough time,
you can get very pretty results with 256 color images. So on poor hardware
(or poor mpeg-software) a FLIC may look better, but on not too old hardware
you get really good video-quality with mpeg, even with small file-sizes (I
have a two-years old pentium 133, which gives me really good mpeg-videos
with the ms-active-movie player, running full screen, nice and smooth
interpolated realtime to 1024-screen size, no extra-hardware, 16-bit
video-resolution, its near to video-recorder-quality).
When i use a software as Graphics-Workshop, then this software will dither
down to 256 colors- thats really worse than 256-color flics with the same
software.

greetings,
Mathias


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From: Tim Glover
Subject: Re: Scientific use of povray
Date: 14 Sep 1998 16:34:58
Message: <35FD6FAE.68F8@nettally.com>
Mathias Bachmann wrote:
> 

<snip>

> When i use a software as Graphics-Workshop, then this software will dither
> down to 256 colors- thats really worse than 256-color flics with the same
> software.

I think this was the actual problem.  My apologies to MPEG. 


Tim G.


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