Delete surface lines outside a boundary

[wilsonm2000]

To avoid huge MMS files, I want to delete lines outside a chosen boundary instead of just choosing a surface boundary in surface definition.  Anyone know a good LISP routine for this, or add-on?  Using "delete line" definition just isn't practical.

[caddie99]

I think this is what you want

https://forums.autodesk.com/t5/civil-3d-forum/answer-day-build-a-surface-that-stops-exactly-at-the-p...

[v-silvestre]

Hi, you could also try using a Cropped Surface.  https://help.autodesk.com/view/CIV3D/2023/ENU/?guid=GUID-D1B688D3-2714-45AF-B367-581476922E8B

Jerry Bartel's has great video going over how to create one:  https://www.youtube.com/watch?v=QSPEYhtlO6Y

[jroot]

This sounds a lot like the wish I had a few years ago:

https://forums.autodesk.com/t5/civil-3d-ideas/breakline-to-triangulate-on-one-side-only/idi-p/950987...

[trumankiko]

it would be nice to have this solved. i had problems with ill-formed boundaries that led me to deleting SO MANY lines in my surface 😞

[Jeew-m]

Hi,

How about using a data clip boundary for surface.

[chriscowgill7373]

I like the Data Clip idea, it is the first boundary in the list, then everything else follows, which is opposite of using a boundary that is destructive.

would something like MAPTRIM work in your case?  I am thinking it might not, as it probably wouldnt be able to break apart the surface definition, but it would be able to remove the source data.