Issues using "SOLID DIFFERENCE" to trim surface in grasshopper

Hi all,

I cannot get this surface to trim with the “solid difference”. Trying to make perforation pattern.

Any help would be GREATLY appreciated.

error_feb112021.gh (14.2 KB)

error feb 11 2021.3dm (2.8 MB)

Thanks!

Your GH file did not upload correctly. Be sure that any referenced geometry is internalized.

Your geometry is not internalized. Strike two…

1 Like

Thanks, edited.

Solid Difference is not appropriate for splitting a surface with curves. You want to use SrfSplit (Surface Split) for that, which as you can see, is extremely slow when you have that many holes (5,606).


error_2021Feb11a.gh (21.0 KB)

Flatten, Group and DeBrep are not necessary.

There are other issues here that are more difficult to explain…

Thanks so much for the help, appreciate it!

One thing about your model that had me confused for awhile is that you used the origin as your reference for Orient ‘A’ (Source) input when in fact, the curve was located VERY FAR AWAY (why?) from there at {-117666.054514, -78127.568524, 0}. It works but makes for very confusing intermediate results.

In this version ‘b’ I used the Area ‘C’ (Centroid) of the curve instead, which makes much more sense. And instead of Group I used the right-click ‘Union Box’ option on BBox to get a box that surrounds all the curves.


error_2021Feb11b.gh (17.6 KB)

I still have no idea what Graph Mapper and Random are doing? But I didn’t try very hard… can you explain that? Is it a form of Random Reduce? Why bother? Maybe you want to keep the curves from overlapping? But that doesn’t work.