             -------------------------------------
             Copyright by Miguel A. Guerrero, 1998
                   All Rights reserved
             -------------------------------------

Please report bugs and suggestions to e-mail: ma_gm@yahoo.com

Table of Contents

1. Disclaimer
2. Revision History
3. Introduction
4. Mode of Operation
4. How to register



1. Disclaimer :
===============

  This software is distributed on "as is" basis. The author disclaims any 
and all  warranties. In no event shall the copyright holder be liable for 
any incidental, punitive, or  consequential damages of  any kind  arising 
from the use of this program. Use  of this software  indicates  you agree 
to this.

This tool is written in Perl. Perl interpreters are freely available on
the internet. You will need to install one to run this tool. The tool
has been tested under MS Windows 95 platform using Perl interpreter for
Win32 build provided by ActiveWare. You can download this interpreter on

                     http://www.ActiveState.com

(look under http://www.activestate.com/pw32/ )

Perl version 5.003_07 is the one that has been used to test this software

Perl may be copied only under the terms of either the Artistic License 
or the GNU General Public License, which may be found in the Perl 5.0 
source kit.

The Perl interpreter should be installed and made available in the path
before executing this tool.

2. Revision History :
=====================

- Rev 0.91 (6/17/98)

First beta release

3. Introduction :
=================

The package contains a couple of programs to create surfaces on AutoCAD.
The two programs are almost the same, but one of them is customized for polar
and the other for rectangular coordinates.

The input to the utilities is a file which contains the function to repre-
sent plus the intervals for the independent variables. These files have ex-
tension .ini. Modify this file using any text editor and the run the program.

The output is an AutoCAD script that you can call-up from inside AutoCAD
The script will draw the surface in front of your eyes.

The software has been tested under AutoCAD 13 for Windows on Windows 95
platform, but it should execute propperly in any other AutoCAD version.

4.  Operation :
===============

Let's see how to create surface on rectangular coordinates, for instance

z(x,y) = x*x + 5*y

with x in [-2,2] and y in [-3,3]

with 10 points in th x axis and 20 on the y for the mesh

4.1) Modify the file "surf_rec.ini"  to look as the following one:

------ << Start of surf_rec.ini >> --------

# Function definition. Use t1 and t2 as independent variables
# NOTE: x,y are defined also as function of t1,t2 to ease change
# of coordinate systems

def_func_x= t1
def_func_y= t2
def_func_z= t1*t1+5*t2

# Limits for 1st independent variable (t1) -----------

# init value
t1_ini=-2

# End value
t1_end=2

# Number of points
t1_pts=10

# Limits for 2nd independent variable (t2) -----------

# init value
t2_ini=-3

# End value
t2_end=3

# Number of points
t2_pts=20

------ << End of surf_rec.ini >> --------

Observe how x and y are expressed also as a function of parameters t1 and
t2 to ease coordinate system transformations. The syntax for the mathematic
expression is Perl syntax. If you need to find out more obout it, check a 
Perl manual (i.e. http://www.activestate.com/reference/Perl/Perl/Perl.html)

4.2) Now, execute on the command prompt :

> surf_rec

a file called fxy.scr will be created with the script that will create
the surface on AutoCAD. This file will be overwritten each time you exe-
cute the program, so if you want to keep a previous result, just rename
it to the desired filename.

4.3) To see the result, open AutoCAD and exeute:

Command: script

Select the file fxy.scr using the dialog box and press OK

4.4) After the surface is built, you can save the file in AutoCAD format
which will be faster than executing the script again

To create a surface using polar coordinates, proceed in the same way but
using the file "surf_pol.ini" to set the input data and surf_pol as the
command to execute on the prompt to create the script file. Remember that
the angle variables (s1 and s2 in this case) are in radians.

5. How to Register :
====================

This utility is Shareware. If you find yourself using it for more than
two weeks, you must register. Send a $15 check (or the equivalent in
your currency) to:

Miguel Guerrero
2175 Decoto Rd. Apt 156 
Union City CA 94587 USA

Being registered you will receive updates to this software at 20%
of its price and information on other low price CAD related sofware
that can improve your design process.

Check "http://members.tripod.com/~ma_gm" for new releases

To complete the registration, e-mail the following information
to: ma_gm@yahoo.com

First Name:

Last Name:

Job Title:

Company:

e-mail:

Please, report any bugs or suggestions you may have to the e-mail above
