Loosing edgepoints

Hey there,

everytime I create planar surfaces of joined curves, the created surface looses its edgepoints.
Same happens, if you trim with joined curves, especially when curves are tangency or curvature.
If you extrude joined curves (tangency or curvature), it happens that you get one single surface instead of one surface per curve.
Are there any solutions for this?

Alex

Yes. In Extrude (also in other surface generation commands), you have the command line option SplitAtTangents, setting it to No will keep G1/G2 surfaces separate.

HTH, --Mitch

any solutions to my other problems?

Nevertheless, switching “splitattangents” to “yes” doesn’t work with g2 or higher surface continuity.
Moreover, if you blend curves with g1 continuity, and extrude with"splitattangents" yes, it does not work every time.

Anyone?

Yeah, sorry, this doesn’t work on G2. The only way I know in this case is to Explode before extruding and then Join afterward.

This should be a bug - do you have an example?

–Mitch

That is expected…

Right- we’ve had some arm-wrestling here about that - the splitter-upper does not, and it is by design, if I remember right, split at all tangents - it does some checking, I believe, to set how much curvature difference there is as well. @dalelear, does this sound right, or am I making things up?

-Pascal

All of this is a direct result of trying to split things up again AFTER the surface creation operation instead of doing the more sensible thing and allowing the user to have the option to not have stuff merged in the first place - i.e. the automatic equivalent of manually exploding polycurves before the operation, operating each separately and then joining the result. This way even if the curves were G100, the surfaces would stay separate…

This would possibly be problematic for something like Loft with multiple profiles that have different structures, but simple for any surface command that uses a single profile as input - Extrude, Sweep1/2 with a single profile, Revolve, RailRevolve, etc.

–Mitch

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Right, that was one side of the arm-wrestle… The other was that this would, or might, make needlessly complex polysurfaces in too many cases and would cause more problems.

-Pascal