Common Line Polylines

[nickburke]

I work for a countertop company and we are constantly pulling apart tops with seams into individual parts.  Is there a way i can make each part of the countertop its own polyline with the seam as the common line?  This way i can just move the pieces onto our sheet stock material.  Right now I run a LISP command to break the tops at the seam lines but if i polyline that, the seam is only connected to one side or the other when I move the pieces.

[rkmcswain]

So, put simply, you have a closed polygon, and you want to split the polygon into two closed polygons - w/o having to do this as a manual process?

Did I understand that correctly?

Thanks.

[nickburke]

Yes, that sounds correct.  I have been messing around with the boundary command but that just makes the polylines on top of the original lines.

[rkmcswain]

Yeah, it would require some programming, which is obviously why you're in this forum. But, for what it's worth, AutoCAD MAP can do this with the MAPFEATURESPLIT command. See below.

[Kent1Cooper]

BOUNDARY or BPOLY and MOVE the results.  A routine could probably be made to do what you want, if it's really that much better than BOUNDARY.  But if that's desired, the way I would imagine it would probably use BOUNDARY anyway, and then Erase the original pieces.

But questions arise:

Would the number of subdividing Lines vary?

Would they always be Line entities specifically, and would the overall shape always be a Polyline entity?

What would be the process you envision, from the point of view of the User?  Grab a counter outline and its subdividing Line(s) in a window?  If so, might there be any other things in the area that it should filter out?  Might there be any other things of the same types as the things you want, that it couldn't filter out so they would have to be ignored in some other way?

This might sound like an odd question, but I can actually think of a reason it would matter for a certain way of approaching it....  Might a subdividing Line ever end at a Polyline vertex, such as a corner, or the tangency point between a straight edge and a curve?

[john.uhden]

I have to agree with @Kent1Cooper.  Mess more with the Boundary command.

Until I wrote smarter programs to do everything for them, the pool liner company to which I consult used the BPOLY command to create the separate panels from their drafting.

[nickburke]

Thanks for your help.  I'll continue messing with Boundary.