Yahoo Tuning Groups Ultimate Backup tuning Re: [tuning] Digest Number 904

Hi Paul,

>Robert, I get silence. But my sound is on and working! I must be unlucky

I've just tested the hexany.wrl in CosmoPlayer, (required a reboot), and it gave a whole string of error messages in the VRML
console, and wouldn't play the midi clips.

It turned out to be because there is an optional description field in an AudioClip node, defaults to "", and CosmoPlayer seemed to
want something there. So I set it to "mid" (at a guess!) and it then worked.

I've uploaded the new version of hexany.wrl, so maybe you can give it a go, especially if you are using CosmoPlayer.

I forgot to try the example .wav sound one, - next time I reboot...

Which browser are you using?

Also you could see if you can find an option to show the VRML console to show error messages. Maybe they'll give some useful info
about what's happening.

Anyway, I'm going to do a bit more searching on the web about AudioClip nodes, and see if I turn up anything more...

You are being a bit unlucky what with Java and VRML sound aren't you...
:(

Robert

🔗Robert Walker <robert_walker@rcwalker.freeserve.co.uk>

>I'm using CosmoPlayer, I re-downloaded hexany.wrl, and there's still no
>sound. How do I get it to show error messages?

Click on the tick below the ? and to left of Cosmo.

Then go to the Advanced tab, and tick "Show console on error or warning".

I've just rebooted and tried the test_sound.wrl out in CosmoPlayer, and it worked okay here.

So it will be interesting to see what error message you get for that one too.

The complaint about the description field which I got here, and fixed, is rather
puzzling - I have just found out that what it is meant to be is a description of the
sound which the browser can use to help people with disabilities, and moreover,
my source of this info said it isn't usually implemented in browsers. So why
Cosmo Player should care what it is and issue a warning because it is missing
is rather a mistery at present!

>P.S. My two dekany movies should give you an idea for what to work on next .
>. . :)

Right, where can I see them?

I have got as far as finding your posting
http://www.egroups.com/message/tuning/11031
and mulling over the fascinating version of Pascal's triangle in the
Wilson archives.

I'm particularly intrigued by the rhombic triacontrahedron - the one with 30 faces.

My research on generalisations of penrose tilings was connected with ways of
obtaining them as projections from slices through regular hypercube tilings in 5
dimensions.

The relevant part is that I also looked at three dimensional versions of these tilings
(I think originally due to Levine).

These are 3D projections from six dimensions, which gave a non periodic tiling
of the whole of 3D space into the two types of golden rhombohedra. They are
shown in the Images section of my home page. You'll see the construction of the
triacontrahedron from them there too.

The 3d Penrose tilings had lots of these triacontrahedra in them. So you can get
thee triacontrahedra in projections into 3D of silces through a regular tiling by six
dimensional hyper-cubes.

In fact there is a way of recombining the cells of this golden rhombohedron tiling to
make a tiling of 3D space by triacontrahedra (the Eikosany), rhombic icosahedra,
rhombic dodecahedra, and the prolate golden rhombohedron, with none of the
oblate golden rhombohedra. (discovered by Soccolar). This (non periodic) tiling
has _lots_ of the triacontrahedra.

I have a feeling they also come up in Coxeter's Regular Polytopes in connection
with higher dimensional hyper-cubes, but can't remember the connection now,
could look it up.

Is there a particular well established set of ratios to use for the rhombic
triacontrahedron? I think this is the one you call an Eikosany?

I could easily do that, and could also do some extra lines inside the triacontrahedron
corresponding the the construction from golden rhombohedra. (Lots more hidden
faces where the tiles meet)

This is the page that introduces the golden rhombohedra, and construction of
triacontrahedron from them, with ray traced images:
http://www.rcwalker.freeserve.co.uk/cubeetc/rhombic.htm

and this is the VRML model of it, which I could add ratios to:
http://www.rcwalker.freeserve.co.uk/interactive_models_with_titles/gr_triacontrahedron.wrl

There's also a rotatable anaglyph on the anaglyphs page.

Rather than type everything in individually, probably I'd do a little program to
make the more complex vrml models - the model of the triacontrahedron made
out of golden rhombohedra was made using a little prog I did especially for it
(and the other two golden rhombohedra models), so could prob. adapt that
for the Eikosany,

And prob. could do some update of the VRML Trees prog. to handle CPS sets
in a more general way, looking a bit further into the future.

(Will be nice to do some more on that - it got within a few weeks of release, then
I got so involved and fasinated by all the tuning related things that I never finished
it, but now they seem to be coming together!)

Robert

🔗Paul H. Erlich <PERLICH@ACADIAN-ASSET.COM>

Robert, I get error messages like

>AudioClip:mid:15_8_35_32.mid: startTime sent to an AudioClip which hasn't
been initialized >yet. Maybe you need to wait until it finishes
downloading?

>>P.S. My two dekany movies should give you an idea for what to work on next
.
>>. . :)

>Right, where can I see them?

Go to http://www.egroups.com/files/tuning/perlich/ and download hexany.mpg,
dekany.mpg, and dekany2.mpg.

>I'm particularly intrigued by the rhombic triacontrahedron - the one with
30 faces.

>My research on generalisations of penrose tilings was connected with ways
of
>obtaining them as projections from slices through regular hypercube tilings
in 5
>dimensions.

Can a 5D cube be projected to a triacontrahedron, or only a 6D cube can?

>The 3d Penrose tilings had lots of these triacontrahedra in them.

I've seen that before.

>In fact there is a way of recombining the cells of this golden rhombohedron
tiling to
>make a tiling of 3D space by triacontrahedra (the Eikosany),

The Eikosany??? Sir, the eikosany has 20 vertices, while the
triacontrahedron has 32.

>Is there a particular well established set of ratios to use for the rhombic
>triacontrahedron?

No.

>I think this is the one you call an Eikosany?

nope.

🔗Robert Walker <robert_walker@rcwalker.freeserve.co.uk>

Hi Paul,

>AudioClip:mid:15_8_35_32.mid: startTime sent to an AudioClip which hasn't
been initialized >yet. Maybe you need to wait until it finishes
downloading?

Thanks!

Error message seems to be saying that the .midi clip hasn't been downloaded properly, though I can't imagine why not.

Just on a long shot, I've done a zip of the .wrl files and all the midi clips, which you can download and browse
off-line. See what errors you get, and if you still get the same one - maybe tell us something.

Could be useful to anyone else who wants to browse it off-line too:

http://www.robertwalker.f9.co.uk/hexany.zip [14 KB]

Also did the .wav one
http://www.robertwalker.f9.co.uk/hexany_with_wav.zip [only 898 Kb]

I've been trying GLView on these - It renders scenes well. Does have a couple of drawbacks - doesn't seem to be easy to spin models
round on the spot as you can in the
others, (or maybe I just haven't discovered how yet). Also if you click on a button that leads to another VRML world, that doesn't
seem to work. But it is pretty good, and fast, in fact the one I use myself a lot of the time for complex VRML files.

It plays the .wav files okay.

However, it doesn't seem to be able to play the MIDI clips. It's not a requirement of a VRML browser that it can recognise the MIDI
format, just kind of recommended.

In fact the VRML spec is a bit like that a bit open ended and looking beyond the current set of VRML viewers.

If you are using a Mac and the Cosmo Player beta, then maybe you can find some other VRML program; I remember I searched a while
back, but it was a bit inconclusive.

Anyway, I'm off to get some sleep now, and I'll see if I think of anything else later.

>Can a 5D cube be projected to a triacontrahedron, or only a 6D cube can?

Have to look it up. The triacontrahedra I was studying were projected from 6D cubic lattices.

>>Is there a particular well established set of ratios to use for the rhombic
>>triacontrahedron?

>No.

Ah, I thought it might be related because it has only six sets of edge directions, rather small for such a complex shape, with 30
faces.

However it would give lots of four note chords, but no triads.

I've downloaded your first dekany movie.

Interesting. I think I can see what the shape is now

= octahedron with alternate faces removed, then you add extra triangular faces, each one joining one of the centres of one of the
removed faces with the centre of the adjacent removed face and the vertex that joins the two removed faces.

Yes, I could do a VRML model easily.

How are the ratios assigned? And which are the triads - the filled in faces?

Robert