QuasiG is a GUI (Windows 95)
Eric Weeks' grey-scale post-script writing Unix quasi-crystal
generator program (quasi.c). It is best viewed with screen resolution
set to 1024 by 768 pixels or higher, but you can get by at 800 by 600
pixels. It was tested on a 24 bit true-colour display setting, but may
work at lower colour resolutions.
QuasiG V1.4 is freeware.
to use QuasiG for non-profit purposes is granted to any person completing
the following steps:
The latest version of QuasiG
is V1.4. You will receive an email shortly with further details for
downloading QuasiG. The download is in a zip file - you will need
Winzip, Ultimate Zip
(freeware) or something similar to extract the program
file. The program file can be extracted to any directory of your choice,
for example, c:\program files\quasig.
5. Enjoy !
Experiment with different parameter
Can you figure out what
range of parameters gives tilings satisfying the Penrose matching rules
site provides an explanation for the methods
used in the algorithm.
Be very patient if you want to apply the Penrose
markings with more than 12 generating lines (24 lines took around 1
minute on a 366 MHz Pentium II laptop). Conjecture: you can tell enough
about whether it's a penrose tiling using just the default 9 lines (or
Feel free to email me (
Click Here )
with any comments on the program or quasi-tiling in
general. E-mail any interesting patterns you generate to me !
QuasiG Techo Details
You don't need to understand a word of the
next two sections in order to use QuasiG. These words are for the techo
types out there...
QuasiG is written in Visual
C++ V6.0, as a 32 bit MDI application using MFC classes. It was my first
attempt at writing such an application, and does some unusual things
- like popping up its configuration dialogs before you've seen a main
window frame, and maximising the document window (you can use the Window/Cascade
or Tile options to change the latter after the windows open).
If you understood
this techno-talk, you might find the SourceFilter
programming utility useful. It's not free, but is pretty cheap. If you
think Quasig is a pretty good bit of freeware, you might consider buying
to help me keep the wolves from the door...
QuasiG Memory Stress
QuasiG generates the tiles
to memory (rather than directly to display). It uses the MFC CArray
class which dynamically allocates space for tiles; the memory is released
when the display window is closed - and varies in proportion to s/2*(s-1)*l^2
where s=symmetries, and l=lines. It can be interesting to plot the Windows
95 System Monitor's memory manager items while running QuasiG. It also
gives your graphics adaptor a pretty serious workout (when running in
colour fill mode).
A Parting Thought
Ever had a fight like this:
It seems that unless you put the hingdorf in the marzidoodle
slot and use default password "crumpet" the framazoogle
bangdoodler won't display correctly. I didn't know that,
so my install failed. If this information had been in a manual
or pamphlet I wouldn't have spent 40 minutes on hold waiting
for your support tech, Kishore, to answer the phone in Mumbai,
and I wouldn't be angry now
Here's hoping QuasiG brings you hours of joy and no such frustration !
27th March 2001, Last Revised
Last Revision: vdeck modification
You are visitor
since 21st Feb 2004.
This material may be used for educational non-profit purposes with
proper acknowledgement of the source. If any images created with QuasiG
are posted on the net, send me the link url. All other uses, please Click Here To