Sunday, April 12, 2015

Do you even cube, bro?

So after I had a chance to acclimate myself to a 7x7x7 V-Cube, I quickly realized that my large Rubik's cube skills needed some work, and so I decided to work on picking out a new 4x4x4. I immediately ruled out a V-cube, since the one thing that drives me a little bit nuts about it is how the blue and the green stickers are too close to the same value (see picture below), so I can't always tell them apart in some lighting conditions.

My first choice based on my familiarity with the mechanism would be a DaYan, but for whatever reason I couldn't find one on Amazon at the time. Since I like stickerless cubes, I got a Cyclone Boys 4x4 FeiYue.

On the off chance I didn't like the mechanism, I got the well-recommended and inexpensive Shengshou.

Both of them turn nice, although considering the only thing I have to compare it to is my original Ideal 4x4x4 from 1982 it's possible that anything might seem better.

I also picked up a Shengshou Megaminx.

As it turns out, I didn't enjoy the physical sensation of turning the Megaminx as much as I thought that I would. Since the part that you turn is just one of the pentagonal sides that represents only a small portion of the puzzle, you don't have the same feeling of manipulating the object that you do with a cube. I was able to solve the Megaminx on my own, just by re-purposing a few standard cube operators like LU'R'UL'U'RU that moves three corners around without moving edges, and variations on RUR'URU2R'.

I was already able to solve the 4x4x4, but I was using a corners-first solution similar to my usual 3x3x3 solution. You solve all of the U and D center pieces, solve the eight corners, solve all of the U and D edges, solve the eight edges in the middle layer, and then solve the remaining center pieces in the middle layer. Now that I have better turning cubes, I have learned most of the edge matching method, where you solve all of the centers, match up all of the edge pairs, and then solve the cube as if it was a 3x3x3. However, there is one problem with the edge matching method - it is prone to parity errors. You can get to the end of solving the cube and have an edge pair flipped around the wrong way, or you can have two sets of edge pairs swapped with each other, or even both of those things at once. Since these are things that can't happen on a 3x3x3 Rubik's Cube, they seem a little disconcerting at first. These can happen because with all of the additional center pieces , there are less constraints on how pieces can appear to be swapped.

Fixing the two sets of edge pairs is easier - swapping the uf pair of edges with the ub pair can be done with the move r2 U2 r2 (Uu)2 r2 u2. If you are unfamiliar with cube notation, check here since it's what I'm using. There are some variations on the notation for larger cubes.

The other case where an edge pair is in the wrong way, that looks like a single edge flip on a 3x3x3 cube, is a little more difficult and harder to memorize. It is r2 B2 U2 l U2 r' U2 r U2 F2 r F2 l' B2 r2.

So another more oddball bit of cubing news comes from yesterday's outing to the beach. I had a couple of the new Hasbro Rubik's cubes in the car, the ones with plastic tiles and the hard-to-disassemble mechanism that I documented here. The logos on these cubes are painted on to the plastic, and up to now I had not worn any of it off in any way. After I applied sunscreen, however, the logo came off the cube I was handling in a minute or two.

Normally people wouldn't have cubes with them at the beach (yes, I'm the only one), but here in Florida there are lots of reasons to apply sunscreen that have nothing to do with the beach.

In other news, in my replay of the God of War games, I am only on God of War 2 so far. I seem to only remember specific puzzles and boss battles in this game, while I was able to remember most of God of War 1 in its entirety. There is less emphasis on narrative, which may be what the difference is, or it may be that there just seems like there's less consistent narrative because I only play for a little bit at a time. The next game I will play is a conversion of one of the handheld games, so that will be quite a new experience for me.

I found out from my older son about a new LEGO game in the works, and I want to be excited about the new Mortal Kombat release, but I think I will talk more about those next time.