[Sketcher] External geometry intersect

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saso
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Re: [Sketcher] External geometry intersect

Post by saso »

mpetrasinovic wrote: Wed Apr 15, 2020 10:14 am I would just add that I think type 2 needs to be combined with type 1 because in essence that is also projection, so at the end, we have projection and intersection tools.
Yes, the difference however is that in type 1 you pick existing edges and vertices from the model, in type 2 the edge that represents the silhuete (or the reflect line) does not really exist so it can then depend on the implementation and how to also keep this parametric and stable. I would not mind if they are separate as long as it would work :)

And similar to my previous comment about picking different elements of the cube for the intersection type, in this case IMO picking individual faces is the preferred solution, I don't think projecting the full silhuete of an object really makes sense.
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saso
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Re: [Sketcher] External geometry intersect

Post by saso »

mpetrasinovic wrote: Tue Apr 14, 2020 3:55 pm We first make 2D Sketches using Sketcher for guide lines and then for cross-sections, cross-sections and guide lines must intersect as you can see from the following image, it would be best to have this kind of tool that makes it easy to make a parametric connection.
It is a different technique, but this example might also be interesting to you https://forum.freecadweb.org/viewtopic. ... 10#p387863
rlrhett
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Re: [Sketcher] External geometry intersect

Post by rlrhett »

To get back to what I think was the original question, is there a way to get a reference to the point where a line passes through a sketch plane? We seem to be discussing projections and reflections, but like the OP I have long splines that I want to intersect so I can fully define the 3D shape by jointing them with perpendicular contour lines. I'm not doing an airplane fuselage, but my application is similar.

Is that a feature in the Link branch? I'm sorry if it was already explained and I misunderstood.

Thanks.
chrisb
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Re: [Sketcher] External geometry intersect

Post by chrisb »

rlrhett wrote: Wed Jan 19, 2022 7:59 pm To get back to what I think was the original question, is there a way to get a reference to the point where a line passes through a sketch plane? We seem to be discussing projections and reflections, but like the OP I have long splines that I want to intersect so I can fully define the 3D shape by jointing them with perpendicular contour lines. I'm not doing an airplane fuselage, but my application is similar.

Is that a feature in the Link branch? I'm sorry if it was already explained and I misunderstood.
You don't want the point where a line intersects a plane but rather a B-spline. I don't know about the branch but in master it can be done with an appropriate attachment. The file uses a DatumPoint at the intersection. This can be used for an external reference in a sketch.
SnipScreenshot-e82f40.png
SnipScreenshot-e82f40.png (9.81 KiB) Viewed 826 times
Attachments
splineCutsPlane.FCStd
(6.56 KiB) Downloaded 49 times
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