The etiquette around here is to post in MPG-1.
I dl'ed your file but Quicktime only showed me white space.

Nikodemus Siivola wrote:

>                       Name: paperplane2.avi
>    paperplane2.avi    Type: AVI (video/avi)
>                   Encoding: x-uuencode

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"Greg M. Johnson" <gre### [at] my-dejanewscom>:

>The etiquette around here is to post in MPG-1.

Ooops... here comes mpeg1 - actually a different, IMO better version.
(Cancelling the AVI.)

 -- Nikodemus

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Attachments:
Download 'folding.mpg' (233 KB)

In article <3a9ab231.15612347@news.povray.org>, tsi### [at] cchutfi 
(Nikodemus Siivola) wrote:

> Ooops... here comes mpeg1 - actually a different, IMO better version.
> (Cancelling the AVI.)

Ah, thanks!
I was also unable to view the previous version, but people didn't seem 
to like it much when I said something about it before, so I didn't say 
anything.
How did you do the folding? Nested unions of triangle objects, or a mesh?
The only practical way of managing mesh triangles that I can think of 
would be to use declared transformations and the vtransform() function 
in MegaPOV...is this what was done?

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><

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On Mon, 26 Feb 2001 16:42:50 -0500, Chris Huff <chr### [at] maccom>
wrote:

>How did you do the folding? Nested unions of triangle objects, or a mesh?
>The only practical way of managing mesh triangles that I can think of 
>would be to use declared transformations and the vtransform() function 
>in MegaPOV...is this what was done?

Basically,

1. Declare control points in plane
2. Manipulate control points (folding macros based on vaxis_rotate()
   and stuff.
3. Declare mesh with triangles composed of control points

The .inc file is in povray.text.scene-files, but I cannot wouch for
it's readability - did a little cleaning up before posting, though.
The folding macros do all the real work. Additionally, there is a
little cheat that applies to two control-points: if they have negative
x-coordinates, their x-coordinates are set to 0 - just to keep the
paper from "tearing".

However, for the past hour I have been thinking of another mehtod:

1. Declare folds (just degrees for each known fold).
2. Declare control points using folds as parameters.
3. Declare mesh with triangles composed of control points.

Kind of neater, I think. Maybe for the next paperfolding thing I
make... I'll have to look into it.

Yours,

 -- Nikodemus

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I did a similar thing some time ago.
I've attached some small examples.

(
Apologies for the awful quality but 
the first AVIs were a bit too large
for my taste and when I converted
those to MPEGs they were half the
size but had similar quality to
these AVIs which are in turn less 
then half the size of the MPEGs.

If the codec is a problem I could
post the larger (file) versions .
)

Since I needed to have images on both 
sides I couldn't use a mesh (or at 
least I didn't know how), so I used a 
thin box with imagemaps, cutting and 
folding. This is a recursive process 
(isn't it?) and it took ages to render.

Come to think of it, I believe I 
posted a message about this before...

Remco
http://www.onwijs.com/

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Attachments:
Download 'pplane1.avi.dat' (17 KB) Download 'pplane2.avi.dat' (26 KB) Download 'pplane3.avi.dat' (22 KB)

Nice ...

A bit of a strange thing happened to my player though:

When I clicked the first AVI, my machine connected to microsoft, and after a
couple of minutes said:

"Cannot play back the video stream: no suitable decompressor could be
found."

I tried again, it did the same. I tried a third time, same response.

So I clicked on your second AVI. It connected to microsoft and installed me
a new Codec. The AVI played fine. I clicked on the third AVI ... Fine.

I clicked on the first again, it plays now.

?  Microsoft site busy ? or damaged codec name in PPLANE1.AVI ?

N.B. I didn't have to download a Codec for you previos post.

Clever animation though, and whatever the problem was, I appear to be able
to play them all now.
--
Duncan Gray
(warning: may contain traces of nut)

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In article <3A9AFF6D.BC7DD671@xs4all.nl>, Remco de Korte 
<rem### [at] xs4allnl> wrote:

> Apologies for the awful quality but 
> the first AVIs were a bit too large
> for my taste and when I converted
> those to MPEGs they were half the
> size but had similar quality to
> these AVIs which are in turn less 
> then half the size of the MPEGs.
> 
> If the codec is a problem I could
> post the larger (file) versions .

These are unviewable on my system, how big are the MPEGs? Are they 
really 4 times as big? Maybe it's the software or settings you are using.
I haven't found any good software for creating MPEGs on a Mac, I'm stuck 
with QuickTime MooV format (which is a good format, but only available 
for Mac and Windows). I don't know anything about the Windows software 
available...

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><

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> 
> These are unviewable on my system, how big are the MPEGs? Are they
> really 4 times as big? Maybe it's the software or settings you are using.
> I haven't found any good software for creating MPEGs on a Mac, I'm stuck
> with QuickTime MooV format (which is a good format, but only available
> for Mac and Windows). I don't know anything about the Windows software
> available...
> 
> --
> Christopher James Huff
> 
Of course I exaggerated, the MPEGs aren't 
really 4 times as big (more like 3 times).
There was also the point of the strange
formats. MPEG did some weird thing to the
edges which makes the result look even 
worse. 
I didn't want to post 3 200K AVIs which 
looked very acceptable and DivX didn't
help much but this Intel Coded (263 I
believe) shrank the sizes so incredibly
I thought I'd give it a try.
Anyway, I've attached one MPEG.

Remco
http://www.onwijs.com/

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Attachments:
Download 'pplane1.mpg' (46 KB)

Remco de Korte <rem### [at] xs4allnl> wrote in <3A9AFF6D.BC7DD671@xs4all.nl>:

>I did a similar thing some time ago.
>I've attached some small examples.

>If the codec is a problem I could
>post the larger (file) versions .

Dunno if it is the codec or my computer, but unfortunately I was unable to 
view these...

>Since I needed to have images on both 
>sides I couldn't use a mesh (or at 

I think that with MegaPOV you could, since all the triangles should have a 
normal vector - and therefore you could use the inside texture thingie. I 
think. Haven't tried.

Actually, it could possibly be done with meshes even in normal POV-Ray, but 
it would have been a bit messy: You can apply textures to individual 
triangles, just make a "hollow" paper, where the top and bottom surfaces 
meet only at folding points, and are something like 0.000001 apart at 
maximum. 

>thin box with imagemaps, cutting and 
>folding. This is a recursive process 
>(isn't it?) and it took ages to render.

Darn I hope I could see this. Before I decided to go the mesh-route I was 
considering something similar, along with a plenty of other options. How 
did you handle the points where the paper is folded several times over the 
same spot?

Yours,

  -- Nikodemus

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