Circle tools

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Circle tools

Postby J-J » Wed Oct 30, 2013 9:35 am

I was playing a bit with some of the newer tools and I stumbled on a puzzling behavior with the circle tools:

1 - draw two circles
2 - select either "2 Tangents and Radius" or "Point, 2 Tangents" to draw a third circle

Now I want to remove the outside section of the third circle, so I pick the "Break out Segment" tool and click the corresponding section I wish to delete, but the whole circle disappears as if it were not intersecting the first two circles.

If instead I pick the "Divide" tool, and click the two intersections (under auto-snap) then I achieve the goal. So, the intersections do exist, but do not seem to be recognized as such by the "Break out Segment" tool...
I am including the test file in case (Win7 - 64)
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circle tools.dwg
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Re: Circle tools

Postby J-J » Wed Oct 30, 2013 10:03 am

to remove the outside section of the third circle


However, "Auto trim" seems to do this action correctly...

If the 3rd circle has a true intersection (not tangential), then the "Beak out segment" tool works as usual.
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Re: Circle tools

Postby Clive » Wed Oct 30, 2013 11:57 am

Hi J-J

I seem to remember a similar problem elsewhere in the bugtracker.
Unless Andrew changes things so that this 'Break-out' tool recognizes intersections of two touching Circles, I would think that the Autotrim tool is the one to use. Circles are 'tricky' little fellows. In principle you could say a Circle has infinite points and angles - these infinite points are equidistant from one point being the center! So all these points do effectively make up a continuous line or a better description would be a continuous closed curve around a center.
Confused yet :shock:
It is probably better to have an additional tool to 'break-out' an arc within a Circle, this way we can pick the starting and end points and break the arc in between.

what do you think?

Using your actual draft, for now if you pick a point more or less opposite the arc you wish to keep it should break out the rest.

Before...picking an opposite point.

Break out 1.png
Break out 1.png (4.99 KiB) Viewed 1102 times



After.

Break out 2.png
Break out 2.png (1.95 KiB) Viewed 1104 times
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Re: Circle tools

Postby J-J » Wed Oct 30, 2013 12:31 pm

Hi Clive,

In order for the "break segment" to operate, one must materialize the tangent point with an intersecting line. No big deal anyway, it was more out of curiosity why this was working! :roll:
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Re: Circle tools

Postby Clive » Thu Oct 31, 2013 10:28 am

Thanks J-J.

I still think it would be good to have a break out tool dedicated to breaking out arcs, so I have added a feature request for this:
http://www.ribbonsoft.com/bugtracker/in ... ask_id=964
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