Message #318

From: Melinda Green <>
Subject: Re: [MC4D] Hi everyone!
Date: Tue, 15 Aug 2006 11:14:16 -0700

Hello Ilia!

Glad to hear from a quiet member. I enjoyed hearing your story.

ilia.smilga wrote:
> […] I don’t understand how you guys manage to solve
> it in less than half an hour: it usually takes me a week or more to
> solve! Once I have tried to solve it as fast as possible in one sitting.
> I’ll never try it again: I spent almost three hours, staring into my
> monitor and trying to imagine how it all worked in 4D; I do not know
> whether my eyes or my brain were more screwed up at the end!

That’s very funny! You may be impressed by a half hour solution but I
have not yet solved the 4D cube with or without Roice’s solution, so I’m
very impressed by your 3 hour solution!

> […]
> I have got a proposal concerning MC4D. There is a problem: it is
> difficult to grasp any single tessie in a single look, especially those
> that have a lot of stickers (edges and corners), because the tessies
> have their stickers spread far apart in the puzzle. The option to
> highlight all the stickers belonging to any tessie is quite handy, but
> not quite sufficient. What if on each hypersticker, each 2D face facing
> another hypersticker had on it a mark (for example, a little square)
> showing the color of the hypersticker it is facing? In this way, each
> hypersticker would bear enough information to identify the whole tessie;
> of course, it would be redundant, but still very useful. In this way,
> you could solve the whole puzzle without making a single 4D rotation!

Your suggestion of the little squares on each cubie face sounds
reasonable. This could be especially useful for showing some of the
state of the invisible face

There is another option which should interest you though in the end it
is probably not practical for solving. Specifically, it is possible to
choose projection parameters such that the stickers of each cubie (or
"tessie" as you call them) exactly touch each other. This is what the
Edit->Edit Prefs->Contiguous Cubies check box is for which works by
locking the face-shrink and sticker-shrink values together so that
adjusting one will change the other to keep the stickers just touching.
There are several problems with this feature but you may enjoy playing
with it. The first problem is that the view does not refresh when you
select the check box. After selecting it, just make a tiny adjustment to
either Face Shrink or Sticker Shrink to see the results. You will then
probably also need to adjust the Eye W Scale and View Scale parameters
to get a reasonable view. The next problem you will notice is that at
some angles, some of the sticker faces will seem to disappear. This is a
problem with our painting algorithm. These views are arguably more
"faithful" to the puzzle than the default one but it does not look
possible to find a parameterization with which you could solve the cube
with reasonable ease.

> Yes, and I have another technical question: I don’t understand at all
> how the macros work. I have tried to use them, but the reference
> stickers system is rather obscure for me, and it seems to me that
> something really weird is going on: I sometimes get the impression that
> macros are executed with one move more or less than they sould have, or
> that some more different cells get twisted that should. Can someone help
> me?

Macros are new to the Java version and are not yet complete or
documented. The use of reference stickers allows you to define a set of
moves that can later be applied to any part of the puzzle similar to the
part where the macro was defined. To do that, you first click three
stickers in whatever pattern is most appropriate for your macro. For
example, if your macro will affect three faces, you might want to click
on one particular sticker on each face. Perhaps the 3 such stickers that
are closest to each other. It doesn’t really matter which 3 you choose.
You just need to be able to remember how to repeat the same pattern when
you go to apply the macro.

Regarding extra or missing moves, it is also possible that you found a
bug in my implementation. Try defining your macro on a pristine puzzle.
Then take a screen shot of the result. Next, reset the puzzle and apply
your new macro in exactly the same place as you had defined it. The
picture that results should be the same. If not, please save your macro
and send me the macro file and the screen shot.

Let me know how it goes, and good luck with the larger puzzles, Ilia!!