Re: How to draw OUTLINES on 3D shapes?
- To: mathgroup at christensen.cybernetics.net
- Subject: [mg1627] Re: How to draw OUTLINES on 3D shapes?
- From: Zorro <berriz at husc.harvard.edu>
- Date: Fri, 7 Jul 1995 00:33:04 -0400
- Organization: Harvard University, Cambridge, Massachusetts
gfairley at wilder.com (Gerard Fairley) writes:
>In comp.soft-sys.math.mathematica Zorro <berriz at husc.harvard.edu> said:
>>Hi. I would like to draw 3D shapes (specifically, spheres and
>>cylinders) as "filled in outlines". For example, a sphere would
>>look like a thin black circle (the outline) around a gray disk (the
>>filled-in interior).
>I don't know what you mean; I thought the outline of a sphere was a
>spherical shell.
No, I mean the 2D outline of the 2D representation (as shown on the
computer screen) of a sphere.
>>Similarly, the outline for a cylinder would be (generally) two
>>parallel lines connected by two half-ellipses, one at each end of
>>the cylinder.
For example, a 2D representation of a cylinder would look something
like
__________
()_________)
while its *outline* would look like
__________
(__________)
Similarly, for a cube, a 2D representation would be
______
/ /|
/_____/ |
| | |
| | /
|_____|/
and the outline of this representation would be
______
/ |
/ |
| |
| /
|______/
It's important to note that I'm not referring to the silhouette (which
would be the 2D figure obtained by filling in the figure above, for
example)
////////
/////////
/////////
/////////
////////
but to the actual 1-dimensional countour we use to represent
the *boundary* of the silhoutte.
Z.