Solid Difference node with multiple closed breps

Hello. The aim is to cut out all geometry inside green oval cilinder on screen. I can just bake it and than delete remained geometry, but is there a way to make it right in grasshoper? Thanks.

Replies to This Discussion

Permalink Reply by peter fotiadis on December 6, 2016 at 4:48am

Like this?

Attachments:

Soild_ops_entryLevel_v1.gh, 13 KB

Permalink Reply by Gudkov Kirill on December 6, 2016 at 9:20am

Thank you a lot! Great lesson. This is right what i needed. maybe you could answer on one more question please. I getting troubles with making solid from lofted surface and patch. It works sometimes, and sometimes not. I notised that it works better with 1.0 unit tolerance, The problem remains even while trying to join baked geometry, so its probably the rhino issue. All breps must be closed.

Permalink Reply by peter fotiadis on December 6, 2016 at 9:36am

Post an impossible (kinda) case.

In general Loft requires "proper" profiles (ideally with the same span points and more or less "similar" [for smooth results]) AND looking to the same direction (classic way to check this is via the dot product [a reference vector VS some vector at, say, profile start - if the topology is "suitable", or via a closed curve orientation vector or ... via a myriad or other ways] - but GH has some native components to offer on that matter).

The patch is another animal (occasionally very freaky)... and ...well... it's a very long story to cover the tricky aspects of that thing briefly here.

All the above are subject to the document tolerance IF you need to "combine" (join) things into some solid (closed polysurface).

Rule of thumb: with a few exceptions ... if you get bananas ... blame you, he he.

Permalink Reply by Gudkov Kirill on December 6, 2016 at 9:42am

thanks for an explaation, i will try to deal with patch or to mind better solution without it.

Permalink Reply by Igor on December 6, 2016 at 12:48pm

Внесу свои 5 копеек.... Чем более плавная кривая, на которой делается патч, и чем больше контрольных точек у самого патча, тем больше поверхность, образующая патч, прилегает к этой кривой, не образуя зазоров. Тогда нормально образуется солид. Кстати, инструмент патча есть также в эддоне LunchBox.

Permalink Reply by Gudkov Kirill on December 6, 2016 at 9:45pm

Спасибо за ответ. Пробовал разные варианты сэмплирования, и много и мало, и fragmented patch, всеравно геометрия получается не очень корректная. Примечательно, что полигон который патчится это почти планарная полилиния - шестиугольник. Решил просто сделать 2 лофта - все работает хорошо, солид делается, из Ланчбокса еще не пробовал.

Set of lofted surfaces instead of patch works fine.