Thread: "POLL: Positive rotation convention"

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In the immortal words of Jayne Cobb: "We're gonna explode? I don't wanna ex=
plode!"

I'm therefore of the same mind as Luna.

Regarding MC4D, I think the reason the current way feels right is because p=
ressing a mouse button feels like pushing /down /on the left or right edge =
of a circle or sphere centered on the mouse. In other words, it's because o=
f how mice physically work and nothing to do with handedness or coordinate =
systems.

-Melinda

On 1/10/2018 12:51 PM, Luna Pe=C3=B1a scarecrowfish@gmail.com [4D_Cubing] w=
rote:
>
>
> I would be in the speedcuber's camp on this one, being one myself, althou=
gh I must say that I could probably adjust to the other way. Honestly, most=
of the notation I use for 4D puzzles is different to yours anyway, and so =
I was planning to just translate.
>
> In terms of swapping left and right click, the current way round make sen=
se to me not as positive and negative, but that right 'feels' clockwise to =
me, and left 'feels' anticlockwise. I'm not sure why, but it's not just sin=
ce using MC4D. I honestly associate right click with positive as it's the c=
lockwise twist, and so your third anticlockwise arguments seems pointless t=
o me.
>
> Just my thoughts.
>
> ~Luna
>
> On 10 Jan 2018 20:45, "Joel Karlsson joelkarlsson97@gmail.com lkarlsson97@gmail.com> [4D_Cubing]" <4D_Cubing@yahoogroups.com ubing@yahoogroups.com>> wrote:
>
> Hello,
>
> While discussing notation (primarily) applicable to 4D-puzzles (inclu=
ding the physical 2^4) with Marc, we encountered a decision of convention w=
hich we could not decide ourselves. Therefore, I want to start a poll to ga=
ther the community's opinion.
>
> The question is: should the positive direction of rotation of a cube =
or a cell of a cube be clockwise or counterclockwise? The rotation is assum=
ed to be performed in 3D-space. With the "positive direction of rotation" I=
mean the assumed direction of rotation around an axis if nothing else is s=
pecified. Ox is a positive rotation and Ox' is the opposite negative rotati=
on; which do you think should be a clockwise rotation and which should be a=
counterclockwise rotation around the positive x-axis?
>
> I'll leave the arguments below. If you have an opinion or preference =
please respond to this post with something like "I think that [insert your =
preference here] should be the positive direction of rotation... [insert ar=
guments here if you wish]".
>
> Best regards,
> Joel
>
> PS. I don't know how long the poll should be open, we'll see when the=
reply-rate drops.
> PPS. If everyone is fine with that, I'll leave my vote as a casting v=
ote in the event of a tie.
>
> *Clockwise (arguments)
> *
> The speedsolvers' convention: Regarding x versus x' turns being clock=
wise, we speedsolvers have read so many dozens (hundreds) of pages using ou=
r notation that it is wired right into our brains.=C2=A0=C2=A0 So, instead =
of our criterion for the best notation being "what seems objectively reason=
able, in principle", our criterion is "what will not make our heads explode=
by being the exact opposite of what we use daily in a very similar context=
..."
>
> As an example, here are a couple of typical pages from speedsolving.c=
om -- a page for a random beginner method, and on=
e of the most commonly used reference pages for the last stage of many peop=
le's solves.
>
> https://www.speedsolving.com/wiki/index.php/8355_Method speedsolving.com/wiki/index.php/8355_Method>
> https://www.speedsolving.com/wiki/index.php/PLL ving.com/wiki/index.php/PLL>
>
> These pages use the notation as defined here,
>
> https://www.speedsolving.com/wiki/index.php/3x3x3_notation ww.speedsolving.com/wiki/index.php/3x3x3_notation>
>
> and use x, y, and z to refer to clockwise turns of the entire cube ar=
ound the relevant axis.
>
>
> My argument is not that the speedsolving community is our largest or =
most important subcommunity, but that it is the group to which this decisio=
n makes the biggest daily difference.=C2=A0 If there's a subcommunity of MC=
4D who read lots of recipes in which "z" means a counterclockwise turn arou=
nd the z axis, then my argument will be invalid on its face...=C2=A0=C2=A0 =
If not, then we'll have to decide whether there is a reasonableness argumen=
t that can override the practical difficulties for speedsolvers in dealing =
with two opposite conventions used so similarly.
>
> *Counterclockwise (arguments)
> *
> 1) For a mathematician or a physicist, the positive direction of rota=
tion is, conventionally, counterclockwise. Always, when talking about rotat=
ions in topics ranging from linear algebra to mechanics the axis of rotatio=
n is defined in such a way that a rotation (of a positive number of degrees=
) around that axis is a counterclockwise rotation.
>
> 2) It follows the right-hand rule. This is a simple rule which helps =
the forgetful to remember in which direction to rotate; if your right thumb=
is the axis of rotation the fingers curl in the direction of rotation.
>
> 3) It's consistent with MC4D. A left click on a sticker in MC4D rotat=
es the cell counterclockwise around the axis pointing from the centre of th=
e cell through the specified sticker. This implies that Ux is performed by =
left-clicking on the right sticker on the U-cell and the same goes for all =
other twists. The axes (in the notation) can be thought of as specifying a =
sticker on the cell (Fx'yz specifying the sticker (on the F cell) in the ne=
gative x-direction (left), the positive y-direction (up) and the positive z=
-direction (front)) and the twist is performed by simply left-clicking on t=
his sticker.
>
> *A third option?
> *
> No, I don't have a third option but there is something which could po=
tentially be a game-changer. If an option to swap the behaviour of left- an=
d right-click would be available in MC4D the third argument for countercloc=
kwise would fail. This argument could then instead be used by the clockwise=
camp since G already breaks the MC4D convention (the axis in the G moves s=
pecify the direction in which the stickers should move and ctrl+left-clicki=
ng on a cell in MC4D rotates the cube in the opposite direction) and theref=
ore, all moves (including G) would follow the MC4D convention if clockwise =
is the positive direction of rotation and the controls are swapped (or you =
prefer right-clicking to left-clicking).
>


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">


In the immortal words of Jayne Cobb: "We're gonna explode? I don't
wanna explode!"



I'm therefore of the same mind as Luna.



Regarding MC4D, I think the reason the current way feels right is
because pressing a mouse button feels like pushing down on
the left or right edge of a circle or sphere centered on the mouse.
In other words, it's because of how mice physically work and nothing
to do with handedness or coordinate systems.



-Melinda

cite=3D"mid:CAK-NJMAs=3DPePPJzd64u2R55+rM7+Gqjw4V+ytD_Xz6Df62sszQ@mail.gmai=
l.com">

I would be in the speedcuber's camp on this one,
being one myself, although I must say that I could probably
adjust to the other way. Honestly, most of the notation I use
for 4D puzzles is different to yours anyway, and so I was
planning to just translate.

In terms of swapping left and right click, the
current way round make sense to me not as positive and
negative, but that right 'feels' clockwise to me, and left
'feels' anticlockwise. I'm not sure why, but it's not just
since using MC4D. I honestly associate right click with
positive as it's the clockwise twist, and so your third
anticlockwise arguments seems pointless to me.=C2=A0

Just my thoughts.=C2=A0

~Luna

On 10 Jan 2018 20:45, "Joel Karlsson href=3D"mailto:joelkarlsson97@gmail.com"
moz-do-not-send=3D"true">joelkarlsson97@gmail.com
[4D_Cubing]" < moz-do-not-send=3D"true">4D_Cubing@yahoogroups.com>
wrote:

.8ex;border-left:1px #ccc solid;padding-left:1ex">

=C2=A0

Hello,



While discussing notation
(primarily) applicable to
4D-puzzles (including the physical
2^4) with Marc, we encountered a
decision of convention which we
could not decide ourselves.
Therefore, I want to start a poll
to gather the community's opinion.>


The question is: should the
positive direction of rotation of
a cube or a cell of a cube be
clockwise or counterclockwise? The
rotation is assumed to be
performed in 3D-space. With the
"positive direction of rotation" I
mean the assumed direction of
rotation around an axis if nothing
else is specified. Ox is a
positive rotation and Ox' is the
opposite negative rotation; which
do you think should be a clockwise
rotation and which should be a
counterclockwise rotation around
the positive x-axis?

I'll leave the arguments below.
If you have an opinion or
preference please respond to this
post with something like "I think
that [insert your preference here]
should be the positive direction
of rotation... [insert arguments
here if you wish]".

Best regards,

Joel

PS. I don't know how long the
poll should be open, we'll see
when the reply-rate drops.

PPS. If everyone is fine with
that, I'll leave my vote as a
casting vote in the event of a
tie.

Clockwise (arguments)

The speedsolvers' convention:
Regarding x versus x' turns being
clockwise, we speedsolvers have read
so many dozens (hundreds) of pages
using our notation that it is wired
right into our brains.=C2=A0=C2=A0 So, in=
stead
of our criterion for the best notation
being "what seems objectively
reasonable, in principle", our
criterion is "what will not make our
heads explode by being the exact
opposite of what we use daily in a
very similar context..."



As an example, here are a couple of
typical pages from href=3D"http://speedsolving.com"
target=3D"_blank"
moz-do-not-send=3D"true">speedsolving.c=
om
-- a page for a random beginner
method, and one of the most commonly
used reference pages for the last
stage of many people's solves.



=C2=A0=C2=A0=C2=A0 class=3D"m_7211080325541458062gmail-m_-5742697122614852616moz-txt-link-free=
text"
href=3D"https://www.speedsolving.com/wiki/index.php/8355_Method"
target=3D"_blank"
moz-do-not-send=3D"true">https://www.sp=
eedsolving.com/wiki/index.php/8355_Method

=C2=A0=C2=A0=C2=A0 class=3D"m_7211080325541458062gmail-m_-5742697122614852616moz-txt-link-free=
text"
href=3D"https://www.speedsolving.com/wiki/index.php/PLL" target=3D"_blank"
moz-do-not-send=3D"true">https://www.sp=
eedsolving.com/wiki/index.php/PLL



These pages use the notation as
defined here,



=C2=A0=C2=A0 class=3D"m_7211080325541458062gmail-m_-5742697122614852616moz-txt-link-free=
text"
href=3D"https://www.speedsolving.com/wiki/index.php/3x3x3_notation"
target=3D"_blank"
moz-do-not-send=3D"true">https://www.sp=
eedsolving.com/wiki/index.php/3x3x3_notation



and use x, y, and z to refer to
clockwise turns of the entire cube
around the relevant axis.





My argument is not that the
speedsolving community is our largest
or most important subcommunity, but
that it is the group to which this
decision makes the biggest daily
difference.=C2=A0 If there's a subcommuni=
ty
of MC4D who read lots of recipes in
which "z" means a counterclockwise
turn around the z axis, then my
argument will be invalid on its
face...=C2=A0=C2=A0 If not, then we'll ha=
ve to
decide whether there is a
reasonableness argument that can
override the practical difficulties
for speedsolvers in dealing with two
opposite conventions used so
similarly.

Counterclockwise (arguments)

1) For a mathematician or a physicist, the
positive direction of rotation is,
conventionally, counterclockwise. Always,
when talking about rotations in topics
ranging from linear algebra to mechanics
the axis of rotation is defined in such a
way that a rotation (of a positive number
of degrees) around that axis is a
counterclockwise rotation.

2) It follows the right-hand rule. This is a
simple rule which helps the forgetful to
remember in which direction to rotate; if
your right thumb is the axis of rotation the
fingers curl in the direction of rotation.

3) It's consistent with MC4D. A left click on
a sticker in MC4D rotates the cell
counterclockwise around the axis pointing from
the centre of the cell through the specified
sticker. This implies that Ux is performed by
left-clicking on the right sticker on the
U-cell and the same goes for all other twists.
The axes (in the notation) can be thought of
as specifying a sticker on the cell (Fx'yz
specifying the sticker (on the F cell) in the
negative x-direction (left), the positive
y-direction (up) and the positive z-direction
(front)) and the twist is performed by simply
left-clicking on this sticker.

A third option?

No, I don't have a third option but there is
something which could potentially be a
game-changer. If an option to swap the behaviour
of left- and right-click would be available in
MC4D the third argument for counterclockwise would
fail. This argument could then instead be used by
the clockwise camp since G already breaks the MC4D
convention (the axis in the G moves specify the
direction in which the stickers should move and
ctrl+left-clicking on a cell in MC4D rotates the
cube in the opposite direction) and therefore, all
moves (including G) would follow the MC4D
convention if clockwise is the positive direction
of rotation and the controls are swapped (or you
prefer right-clicking to left-clicking).