June 17th is World Tessellation Day - chosen because it is the birthday of M. C. Escher.
Some light reading:
Tessellation Patterns - From Mathematics to Art
If anyone wants to present some calculator generated patterns (50G/Prime/DM42) then please do!
Is this one for HP50 correct ? The GROB is 500x500 but I forget how to change GROB -> JPG
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My idea is a kind of "RPL Logo" to get a motif and the to assemble it.
Code:
DIR @ RPL Logo
ClrScr @ Create a virtuel screen 500x500 pixel, (0,0) in the center
« #500d DUP BLANK PICT STO PICT SIZE B->R SWAP B->R
2. / DUP NEG SWAP XRNG 2. / DUP NEG SWAP YRNG »
SetAng @ Set Angle
« 'AngTrt' STO »
SetPos @ Set turtle pos
« 'PosTrt' STO »
RazTrt @ Init Turtle in the center
« (0 0) SetPos 0 SetAng 99 SF »
Raz @ Initialisation
« ClrScr DEG ERASE RazTrt »
Lt @ Tourne gauche : left
« 'AngTrt' STO+ »
Rt @ Tourne droite : Right
« NEG Lt »
Fw @ Avance : Forward
« AngTrt DUP2 COS * UNROT SIN * R->C PosTrt + DUP
PosTrt IF 99 FS? THEN LINE ELSE DROP2 END 'PosTrt' STO »
Rpt @ Repeat n time
« 1 SWAP START DUP EVAL NEXT DROP »
END
And then things like :
Code:
« { 10 Fw 60 Rt } 6 Rpt » 'Hexa' STO
Raz { { Hexa 60 Rt 20 Fw } 6 Rpt 30 Fw } 6 Rpt
or
Code:
Raz
{ { { Hexa 60 Rt 20 Fw } 6 Rpt 60 Rt 40 Fw } 6 Rpt Hexa 60 Fw } 6 Rpt
etc.
Certainly by now you've seen the "headline" news about the
aperiodic "HAT" polykite Einstein? It has some interesting properties. When it was announced, I sat down with pencil and paper to calculate the unit area of each "stone". Somehow that wasn't in any of the papers ( or if it was I missed it? ).
Arxiv:
https://arxiv.org/abs/2303.10798
Hi,
Sorry, I didn't have time to post this last weekend.
So here is, with a little delay, what to do with the tiling of the infinite plane using your HP-41 provided you know how to aim to print ...
The patterns on the calculators are pretty neat!