Hi all,
As some of you may know that Gelatinbrain(GB)'s applet contains hundreds of=
3D puzzles. Now two 4D puzzles have been added. To see them, please go to
http://users.skynet.be/gelatinbrain/Applets/Magic%20Polyhedra/dodeca_f0.htm
then wait for it to load (it may take two or three minutes). Then switch pu=
zzles by clicking the "File" button on the top left corner, then following =
New > tessaract to find 8.1.1 or 8.1.2.
8.1.1 is 2x2x2x2. 8.1.2 is the deep-cut (half-cut) RT hypercube, which can =
also be found in MPUlt 1.09 as 4D_half_RT.=20
There have been discussions between the GB solvers and GB here:
http://twistypuzzles.com/forum/viewtopic.php?p=3D271270#p271270
Neither of them has been solved in that applet yet, according to the rankin=
g page. I'm not comfortable solving the 2^4 without using macros -_-;
There are some unique features in GB that's not there in MC4D or MPUlt.=20
(1) It has two views. So the hidden cell is directly visible.
(2) The global orientation of the puzzle is automatically snapped to some f=
ixed angles. The rigid viewpoint has pros and cons. For example, if the mac=
ro function becomes available (GB is working on it), one can apply macros w=
ithout specifying the reference point. This is less flexible but pretty con=
venient.
(3) When a puzzle is solved, the move counts and time are automatically sub=
mitted to a scoreboard.=20
There are also differences between GB's puzzles and the corresponding exist=
ing puzzles here. As Brandon pointed out, the moves in GB are limited to 90=
-degree turns only.=20
(1) In MC4D one may click on edges or corners to do 120 deg or 180 deg turn=
s. But in GB 8.1.1 these moves not allowed.=20
(2) In MPUlt > 4D_half_RT, when turning around the face between cells A and=
B, one can use a single move to swap the whole cells A and B, affecting so=
me other cells. This kind of moves are not allowed in GB 8.1.2. The 90 deg =
turns only rotate cells A and B without swapping them.
In spite of the limitation, GB 8.1.1 reaches all the states of the "fully f=
unctional" 2^4; and GB 8.1.2 reaches all the states of 4D_half_RT in MPUlt.=
The latter statement is not straightforward but is true, because using onl=
y 90 deg turns one can do arbitrary 3-cycles.
In conclusion, we have a new software implementing 4D puzzles. The author, =
Gelatinbrain, is also a talented and diligent programmer. I would expect mo=
re 4D puzzles coming in GB's applet.=20
Nan