Search found 71 matches

by Dinogeorge
Wed Mar 19, 2008 11:28 pm
Forum: Stella Forum
Topic: Compounds of 10 regular polychora
Replies: 12
Views: 38683

Another view

Here's a view of the compound of ten grand 600-cells 0.555 3D cross section a bit off center, so that it looks like a surrealistic planetoid with tall peaks and deep valleys that you're passing over in a spaceship. http://members.aol.com/Dinogeorge/Tengrand600cellsoffcenter.gif This one is in ten co...
by Dinogeorge
Fri Mar 14, 2008 7:05 pm
Forum: Stella Forum
Topic: Uniform compounds of icositetrachora
Replies: 3
Views: 15466

“Lesser” compounds of icositetrachora

Coxeter’s list of “regular” icositetrachoric compounds in Regular Polytopes altogether includes seven: the (incompletely) self-dual compound of five, two mutually dual compounds of 25 (“scrunched” and “strewn”), two mutually dual compounds of 100 (“scrunched” and “strewn”), and two mutually dual com...
by Dinogeorge
Mon Mar 10, 2008 4:41 am
Forum: Stella Feature Requests
Topic: Dual colors
Replies: 3
Views: 14574

Dual colors

What do you use to change the colour of a part in the compound? If you just hit "c" (same as "Color->Replace Cell Color Throughout") it will only change colours in the base model, not the dual. But if you use "Color->Set Color of One Part in Compound" (no keyboard shortcut) then it will affect the ...
by Dinogeorge
Sat Mar 08, 2008 8:33 pm
Forum: Stella Feature Requests
Topic: Dual colors
Replies: 3
Views: 14574

Dual colors

I could use a "color dual compound same" option in Stella4D for coloring dual compounds: color the components of the dual compound the same colors as the corresponding components of the original compound. In the current version, the colors of a dual come out oddly--sometimes they're random, and some...
by Dinogeorge
Sat Mar 08, 2008 12:08 am
Forum: Stella Forum
Topic: Uniform compounds of icositetrachora
Replies: 3
Views: 15466

Compound of 450 icositetrachora

This is the compound of the “scrunched” and “strewn” compounds of 225 icositetrachora each, in dual position. As such, it has the 600 corners of the “scrunched” compound, where nine icositetrachoric vertices come together, along with the 2520 corners of the “strewn” compound. Of those latter, 2400 h...
by Dinogeorge
Sun Mar 02, 2008 4:52 pm
Forum: Stella Feature Requests
Topic: Funny pointer
Replies: 3
Views: 15843

Re: Funny pointer

I didn't think to use the Space bar. So I tried it out and it does bring up the crossed-arrow cursor in a way I can control. Next time the cursor is stuck in that mode, I'l try hitting the Space bar a few times and see what happens. Hitting the Space bar works fine. I've opened Stella4D and had an ...
by Dinogeorge
Sun Mar 02, 2008 1:05 am
Forum: Stella Forum
Topic: Uniform compounds of icositetrachora
Replies: 3
Views: 15466

“Strewn” compound of 225 icositetrachora

The dual of the “scrunched” compound of 225 icositetrachora is the “strewn” compound. The 225 “scrunched” icositetrachora dualize into 225 like polychora that are distributed differently to make up the “strewn” compound. Specifically, there are more corners in the “strewn” compound, with fewer icosi...
by Dinogeorge
Fri Feb 29, 2008 6:51 am
Forum: Stella Forum
Topic: Uniform compounds of icositetrachora
Replies: 3
Views: 15466

Uniform compounds of icositetrachora

There are lots of symmetric compounds of icositetrachora (including at least one infinite set, discovered, if I remember correctly, by Jonathan Bowers), many, but by no means all, of which are vertex-regular, cell-regular, or uniform. The simplest is the compound of the icositetrachoron and its dual...
by Dinogeorge
Thu Feb 28, 2008 5:09 pm
Forum: Stella Feature Requests
Topic: Funny pointer
Replies: 3
Views: 15843

Re: Funny pointer

My guess would be that hitting the Space bar will get you out of that mode again though. Let me know next time it happens. I didn't think to use the Space bar. So I tried it out and it does bring up the crossed-arrow cursor in a way I can control. Next time the cursor is stuck in that mode, I'l try...
by Dinogeorge
Thu Feb 28, 2008 8:28 am
Forum: Stella Feature Requests
Topic: Funny pointer
Replies: 3
Views: 15843

Funny pointer

Hey, Rob-- Every so often when I start up Stella4D I find the cursor in this really annoying mode where it looks like a pair of crossed double arrows. I can't get the polyhedron on display to tumble; all it does is move around the screen when I pull the cursor around. And I can't find any place in a...
by Dinogeorge
Thu Feb 28, 2008 3:11 am
Forum: Polyhedra
Topic: Books about Polyhedra
Replies: 10
Views: 36499

Re: Cundy & Rollett

I don't have Mathematical Models , but have photocopies of a few relevant pages. I don't think they describe constructing the 5 cube model in this way. They seem to just describe nets for the external parts. You're right. I checked my copies of all three editions of C&R and none describes putting t...
by Dinogeorge
Tue Feb 26, 2008 12:33 am
Forum: Stella Forum
Topic: Compounds of 10 regular polychora
Replies: 12
Views: 38683

Ten grand hexacosichora

The compound of ten great icosahedral hecatonicosachora in a hecatonicosachoron is one of the first I built with Stella4D once I discovered it was making compounds it had failed to create before. I posted pictures of a section shortly after this forum opened. So here I present it again, this time pa...
by Dinogeorge
Mon Feb 25, 2008 8:07 pm
Forum: Polyhedra
Topic: Books about Polyhedra
Replies: 10
Views: 36499

Cundy & Rollett

There was one book, the title of which I've forgotten, which included nets for the compound of 5 cubes. They suggested a very sturdy construction, first building a single cube, then covering each face with another part turning it into a compound of 2 cubes, and finally adding a third level to compl...
by Dinogeorge
Mon Feb 25, 2008 7:55 pm
Forum: Stella Forum
Topic: Compounds of 10 regular polychora
Replies: 12
Views: 38683

Ten great icosahedral hecatonicosachora

Personally, I like the cross-sections of the great icosahedron . A small animated one can be seen on the page above, but here's a larger single frame, this time taken at 0.310 for aesthetic appeal: http://i225.photobucket.com/albums/dd237/RobertCWebb/GreatIcosa-Slice0310.gif Rob. Very nice :!: Spea...
by Dinogeorge
Mon Feb 25, 2008 7:58 am
Forum: Stella Forum
Topic: Compounds of 10 regular polychora
Replies: 12
Views: 38683

Ten grand stellated hecatonicosachora

This, as far as I know, is “humanity’s first look” at the compound of ten grand stellated hecatonicosachora in a hecatonicosachoron . As with the preceding compound, I painted it with just two colors (orange and maroon), one for each chiral subset of five. Where the external facelets are coplanar, t...