Lathe v0.9b
by Steve Sprang
<sprang@andrew.cmu.edu>
http://www.andrew.cmu.edu/user/sprang/newtonsoft.html

September 15, 1997


Introduction
============

Lathe is a simple 3D modeler for Newton OS devices. A template, specified in
2D, is "lathed" to create a 3D wireframe model.


Non-MP2K users
==============

Lathe was developed on an MP2K and the performance on that device ranges from
great to acceptable (depending on the model complexity). Unfortunately, I don't
have direct access to an older Newton but a friend who tested it for me
indicated that it was somewhat slow on an MP120. For MP120 and MP130 users, your
best bet is to keep your models as simple as possible.


Usage
=====

3D-View
-------
The 3D-view is the main area of interest in Lathe. This is where the model
is displayed. If you tap your stylus within this view and drag it around you
can rotate the model in real-time. On Newton devices which support grayscale, 
model segments which are further away will be drawn with successively lighter
shades of gray.

Template-View
-------------
This view shows the 2D template that is revolved to generate the 3D wireframe. 
The template is revolved about the top edge of the view.

Tools-View
----------
The currently selected tool determines how your stylus will interact with the
points displayed in the Template-View.

The first tool is the "move" tool. This simply allows you to tap on a point
in the template and drag it to a new location.

The second tool is the "add" tool. This tool allows you to add more points
to the template. A new point is added by tapping on a line segment between
two existing points, or tapping near one of the endpoints.

The third tool is the "remove" tool. This allows you to remove points in
the template by tapping on them.

Note: Each modification to the template forces a regeneration of the model.
If your model is sufficiently complex, or your Newton is rather slow, this
may cause a large delay. In the future, I'll probably provide an option to
turn off auto-updating.

Detail Slider
-------------
The detail slider allows you to specify how many times you want the template
to be repeated within the 3D model. The more times the template is repeated
the better it will look, but the longer it will take to draw and rotate.

Arrange Popup
-------------
The arrange popup-button allows you to automatically organize the points in
the template in specific ways. The currently available options are: Cone,
Cylinder, Sphere, Torus, and Glass.

Selecting one of these options will rearrange the points to generate the 
corresponding 3D object.

Note: All of these options (except Glass) preserve the number of points in
the template.

Undo
----
All actions that change the template points: Move, Add, Remove, and Arrange,
can be undone by tapping the standard Newton "Undo" package.


License and Distribution
========================

Lathe is freeware, although I'd really appreciate hearing from you if you have
good things to say about it. Oh, and if you're feeling really generous, I won't
turn away monetary donations. ;)

Please feel free to distribute Lathe in any way that you can. I only ask that
you don't make money off of it.


Contacting the Author
=====================

Send all your questions/comments/bugs to:

email:	<sprang@andrew.cmu.edu> OR <ssprang@cs.cmu.edu>
		
U.S. Mail:  Steve Sprang
            141 State Route 603
            Shiloh, OH 44878
			
URL: http://www.andrew.cmu.edu/user/sprang
