Date: 9 Jan 1981 1648-PST
From: Dave Dyer
Subject: nomenclature
To: cube-lovers at MIT-MC
The real problem with RLUDFB is that it is nearly impossible for
the casual observer to determine if two "transformations" are the
same or not. Transformations should be described such that there
is ONE description of each transformation. We can't really get all
the way to the ideal, because there are discinct sequences that lead
to the same termination. But we can eliminate a lot of the confusion.
I Propose that all transformations be described in terms of twists
done by both hands without changing the overall cube orientation.
my proposed primitives are
1 "forward" twist of left or right face
2 1/2 twist of left or right face
3 "backward" of left or right face
URF orient the cube to work on named face,
with your right hand. Names are lambda-bound from the
start of the transformation. To instantiating a transformation
one can simply substitute the color for the orientation label
notation is <(optional) left hand>
For example, a sprat wrench:
UDLRFB calls it: RL' U RL' B RL' D RL' F.
I call it: R11 U1 R11 F03 R11 U03 R11 F1
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