Re: Traveling Salesman Syndrome

--- In CAD_CAM_EDM_DRO@y..., "Carol & Jerry Jankura"
<jerry.jankura@s...> wrote:

> Fred:
>
> Am I correct in my thinking that the "reorganize" command of

VectorCAD takes

> care of "drawing" the object in a manner that attempts to minimize

the

> number of extraneous moves?

It does not change the drawing in any way. It simply changes the
order of selection. Draw 9 points in a 3 x 3 grid. Click select
them in any order(randomly is good). Special simulate to see the
order of selection. Is it random & inefficient? OK

After you are certain of the order, Change-reorganize. Now Special
simulate again and you will see that the points are now selected in a
precise zig-zag manner that is about as good as you will get, without
some serious simulation and optimization algorithms. The bottom line
is that this technique gets you to 97%, and the last 3% is too
expensive to bother with, especially for hobby/small shop lot sizes.

Interesting with 9 points, if you select the center one, and then the
outer ones at random, or even intentionally opposite & inefficiently,
the reorganize will always pick the first one first (that is the
definition) and then proceed around the outer points in order either
clockwise or counterclockwise. It seems to prefer CW, but I'm not
sure why that is. Some kind of right hand left hand bias on the part
of the programmer?

By the way if you have a closed contour or even an open chain and you
select it at random, jumping around to different lines or arcs on the
periphery, including reversed direction, Re-organize will also do the
same thing with the contour, in that it will be re selected from the
first entity selected, forward in its selection direction.

Best Regards,

Fred Smith
IMService