STLPACK.EXE v0.35
(c) Evgeny Kotsuba 1997-1999

1.0 What it is.

STLPACK.EXE is multiplatform compressor for STL files, de-facto
standard for Rapid Prototyping systems. (Laser Stereolithography
Apparatus is most known Rapid Prototyping technology and STL stands
for STereoLithography)

1.1 Why it may be needed.

STL format is very simple and well suited for RP applications 
but there is one problem: STL files have very big size. 
Even in binary form. Typical size for mechanical models is 0.2-2Mb, 
for medical applications (RP copy of computer tomograph images) -- 
5-50Mb. If you want to transfer such files via Internet with 
modem bps even 2kb/sec, this problem becomes PROBLEM. 
On the other hand, if you maintain archive of STL models 
then you also sometime will face with that problem. 
Usual compression reduces size of STL, but problem remains.

1.2 Licence

This software is Freeware in terms of GNU public licence.

You cannot delete author information; you cannot change exe file, 
do reverse engineering, etc.

1.3 STLPACK made in Russia 
    from natural components... ;-)

1.4 Where it can work.

STLPACK is text mode application for IBM PC. 

OS             Distribution file      Comment
---------------------------------------------------- 
DOS          - STLPACKD.ZIP           Need DOS4GW Dos extender  
OS/2(3/4/5)  - STLPACK2.ZIP           Compiled for Pentium and higher
Win95/98/NT  - STLPACKW.ZIP           Text mode (console) application !
FreeBSD      - STLPACKF.ZIP           may be it will work in Lunix 



2.0 Using STLPACK

STLPACK reduces the size of STLs better than filecompressors, and more,
you can use your favorite compressors for consequent packing  output
of STLPACK. For example, you can use it as:

To compress STL file:

STLPACK YourFile.STL YourFile.STP
ZIP YourFile.ZIP YourFile.STP

To decompress STL file:

UNZIP YourFile.ZIP 
STLPACK YourFile.STP YourFile.STL

I recommend to use RAR 2.0 or any from zip family.

2.0.1 On Windows95/98/NT for better performance I recommend
 to use STLPACK from "rulez" filecommanders, i.e., FC, Far, VC.

2.0.2 Memory requirements. While compressing, STLPACK uses memory
about twice more than binary STL file size. While decompressing 
STLPACK uses more than binary STL filesize.

2.1 STLPACK can read text STL file, but decompress STP only to binary STL.

2.2 STLPACK test STL file for some errors. In case of non-fatal errors
 it prints info on these errors.

2.3 After creating STP file STLPACK always read STP, decompress it in
memory and compare it with source STL. Usual error is the normal's 
difference, normally such errors occur from degenerated facet.
In case of severe error STLPAK print something like:

[1234]Vertex[1][0] Diff = 1.234
source stl1.f[1234].iVertex[0]=567
taget  stl2.f[1234].iVertex[0]=789
  
In this case please E-mail me bugreport with rar'ed or zip'ed source STL.
If total size of bug rar/zip will be more than 1 Mb, please split it in parts;
Don't mail me if total size is more than 10 Mb (this is my mail box size 
at my provider)

2.4  Table of file sizes:

filename        STL	  STL+zip  STL+Rar   STP      STP+ZIP  STP+RAR
-----------------------------------------------------------------------
femur.stl      17828084   7537791  7321134   4367010   2250182  2149771
CTR data 

srt01_v.stl	2523484   1090787  1059437    524492    331962   325661    

SR1.STL         2521584   1196169  1067850    556901    385387   366677      

robotb.stl	2360634    708608   594366    524765    265591   242009

kasko_o.stl	2274784   1020121   996673    454742    337709   332733

BOTTLE	 STL	 685684    267319   250833    134759     65360    62404

CARWHEEL STL	 358284    108589   99417      74085     49263    47203

PUMPE	 STL	 314184     90467   86186      62956     32707    32065   

CONES	 STL	   7384     2820     2740       1483      1272     1223  
--------------------------------------------------------------------------
Sum	       28845222  12022671  11478636     6701193   3719433  3559746
Typical medium 		   41.79%    39.79%     23.23%    12.89%   12.34%
Compression Ratio                              
--------------------------------------------------------------------------
3d_stl.stl     35503684  4187486    3903403   7427921   2376237   1878741   
very non-smooth,         
made from small 
cubes, CTR data.
--------------------------------------------------------------------------
Total Sum      64348906  16210157  15382039   14129114   6095670 5438487
Medium Ratio		   25.19%   23.90%      21.95%   9.47%    8.45% 

                                                
3.0 Feedback.

Please e-mail me the following form:
---------------8<-------------------
3.1 I test STLPACK on
[ ] DOS
[ ] Win95/98
[ ] WinNT
[ ] OS/2
[ ] FreeBSD
[ ] Other, please specify  _______

3.2 My impession

[ ] Fine
[ ] Good
[ ] Medium
[ ] Bad
[ ] Bug
Your comments ___________

3.3  Yes, I want to use STLPAK on

[ ] DOS
[ ] Win95/98
[ ] WinNT
[ ] OS/2
[ ] FreeBSD
[ ] Other, please specify  _______


---------------8<-------------------

4. Author info:

E-mail: laser.nictl@g23.relcom.ru


WWW:    http://www.laser.ru/stlpack - Homepage for STLPACK
WWW:    http://g23.relcom.ru/g23/9749/stlpack 



5.0

What's  new:

v0.35: FreeWare 

v0.34:
- improve error handling for damaged STL files


v0.33:
- compiled for DOS, Win95/98/NT, FreeBSD
- improve compression
- improve error handling for damaged STP files
- change recommended usial file compressor from ZIP to RAR 2.0

v0.31:
- slightly improve compression speed
- slightly improve error handling

v0.2 first public release for OS/2
