OG on circle

[Krischu]

I found that creating a POLYLINE (OG) from a CIRCLE does not work. But DiViding the CIRCLE into two adjacent ARCs works out.
Just as a note for comment.

[CVH]

Activate OG
Look below.

Untitled17.png (4.81 KiB) Viewed 4821 times

[Husky]

I found that creating a POLYLINE (OG) from a CIRCLE does not work. But DiViding the CIRCLE into two adjacent ARCs works out.
Just as a note for comment.

I don't understand this statement. Explode a circle and you get a polyline in a circle shape. What isn't working?

[Krischu]

Activate OG
Look below.
Untitled17.png

Yes, as soon as you have made ARCs of the CIRCLE or have exploded the CIRCLE. But you cannot vonvert a CIRCLE directly to a POLYLINE.
Once you know you have to explode it, fine. But I stubled across it when I tried to convert that LOgo I posted and found that the (R)-trademark circle did not convert to POLYs in the first try.

[Husky]

But you cannot vonvert a CIRCLE directly to a POLYLINE.

Again! Yes you can!

circle - > explode = polyline

[CVH]

Guys, we are repeating things again.
All this already passed the revue not that long ago.
But the info is scattered in different topics.

A Circle explodes to a Geo closed Logically open Poly with 3 vertices.
Both bulges are 1 or the Arcs are 180 degrees.
Start and End-point are situated at the 0 degree position of the circle.

With OC a selected Circle is tranformed to a Logically closed Poly with 2 vertices.
Both bulges are 1 or the Arcs are 180 degrees.
Startpoint is situated at the 180 degree position of the circle.
The endpoint is logically the same as the startpoint.

Why the difference?
Don't care, very happy with the two different outcomes.

The method OC takes the selection as source regardless of what is selected.
Those that don't comply are skipped.

In se, Polys consist of strings of Line segments with a bulgefactor.
0 = straight, 0.414214... = 90 degrees, 1 = 180 degrees.
(With a limit at infinity that would resolve to a full arc).
Or in other words Line segments and Arc segments (except a full arc).
But you can't fit anything else in there.

The OG method takes a Line, an Arc or a Poly as entry...and a Spline.
The purpose is to connect loose segments by endpoints that meet the tolerance.
Circles (and full Ellipses) don't have endpoints.
OG will end when the tolerance isn't met.
It is looking for one string only.
The OC method will continue untill all selected are processed.

Both OC and OG have a tendency to look for long strings and/or to close the string.
OG can handle closed Polys dynamically whith connections at vertices.
OG creates Geo closed forms.
OC will prefer to keep those as Logically closed.
Both can handle open and closed Splines.
Only approximated with Arc and Line segments these Splines can be translated to Poly strings.

OC returns all closed and/or open strings it can generate from the selection.
That includes a Circle appoximated with not less then two Arcs.

Altough possible, a 'round' Poly never gets included in an other string.


Regards,
CVH

[CVH]

I don't understand this statement.

Husky, me neither.

First I thought Krischu was starting to summerize what functions can't do.
A hell of a job. Don't stop him.
Then it became obvious he simply wasn't reading the instructions.
That simple rule of text in the screenshot say's it all.
Then the topic changed to Ci2Poly.
And, yes you can.
And that info is provided here not so long ago.
Nothing new there, he tend to read our replies half.
And it doesn't serve to post a fixed file.
Lets try something else.


Krischu, please read:
https://qcad.org/doc/qcad/latest/refere ... ts_en.html
https://qcad.org/doc/qcad/latest/refere ... on_en.html
As pro you may include Splines when appropriate in those texts.

Regards,
CVH