simple geometry draws twice

[a...@johndeckert.com]

Hello --

I fired up my Eggbot for eggs again this year with a new computer and all new software.

The one exception is that I apparently no longer have access to my Adobe License for Illustrator.

So now I'm drawing in Inkscape.  

My computer is an iMac with Sierra version 10.12.3

I installed XQuartz 2.7.11 (org-server 1.18.4)

I installed Inkscape version 0.91 (created Jan. 31, 2015)

I installed EggBot Control software release 2.7.1 (dated 2016-01-11) 

So here's the problem:

With a simple rectangle the pen draws a partial leg and completes the other three legs.

THEN the pen doubles back to REDRAW all four legs, the exception being that all four are complete.

I used the RECTANGLE TOOL

Then to be extra certain I ain't got nothin' amiss, I UNGROUP the rectangle

Then I Convert OBJECTs to PATHS 

Then, in desperation, I Convert STROKEs to PATHS.

I ALSO have NO FILL and even tried it with NO STROKE color and NO STROKE width.

Anybody know how I can get it to draw just ONE rectangle COMPLETE?

Thanks,

John D

[Windell H. Oskay]

> On Apr 2, 2017, at 11:30 AM, a...@johndeckert.com wrote:
>
> With a simple rectangle the pen draws a partial leg and completes the other three legs.
> THEN the pen doubles back to REDRAW all four legs, the exception being that all four are complete.
>
> I used the RECTANGLE TOOL

> Then, in desperation, I Convert STROKEs to PATHS.

> Anybody know how I can get it to draw just ONE rectangle COMPLETE?
>
> Thanks,
> John D

Hi John,
You are finding two unrelated issues.

For the partial leg: It sounds like you're not allowing enough time for the pen to get all the way down before your plot starts. That's a matter of your EggBot settings and/or mechanical positioning. Check that the pen rides a consistent height above the egg over its full range of travel. Then, you may wish to choose a faster pen lowering speed (suggest 100%) and/or a longer delay after lowering the pen (suggest 400 ms).

The Stroke to Path operation is what is causing the double lines. Stroke to Path takes a single path -- that is, a line drawn with a certain width, and replaces it with two paths that are that width apart. It then draws the new object with no stroke, but a fill between the two new paths.

If you could first imagine a simple circle of diameter 100 px, with no stroke, but a solid fill. We then apply a stroke of width 10 px and turn off the fill. The objects size is now 110 px wide and tall, because stroke widths affect the overall size of the object, and the stroke is applied along the centerline. At this stage, if you plotted the object, you would get a single circle with a line width determined by the width of the pen that you are using.

Now, let us apply the Stroke to Path operation. Visually, there is no change. However, the object is quite different: It is now the filled region between two circles, one of diameter 90 px, and the other of diameter 110 px. In order to see these, you can turn off the fill and apply a stroke to the object. (And, if you would like to separate the two circles, you can use Path > Break Apart.) Now, after the Stroke to Path operation, since there are two circular paths in the drawing, it would plot as two separate circles as well.


In your case, with the rectangle, I'd advise you to stop before the Stroke to Path, unless you do want the double lines.

Cheers,
-Windell



Windell H. Oskay, Ph.D.
Co-Founder and Chief Scientist
Evil Mad Scientist Laboratories
175 San Lazaro Ave, STE 150
Sunnyvale CA 94086
http://www.evilmadscientist.com/

[a...@johndeckert.com]

Thank you, Windell!