EDIT: yep , this definition is a total mess.
This part here doesn’t make sense:
You extract the centroid point, but the you use it as UV coordinate “Point” to extract a location/frame/normal in the surface, which is that green arrow on the base.
Then you use that direction to extrude your whole shape to create a
Linear extrusion.
The resulting shape is a literal impossible shape, with a thickness that constantly change from positive thickness, zero, and
negative thickness.
This is why you holes sometime end up result as if you are adding material instead of subtracting.
Replaced this part with a one-liner in c# to create an actual Brep offset.
Tip: step by step, bake your geometries on Rhino and manually check if the shape make some sense to you.
Here you subdivide your surface into actual quadrilateral chunks and then use
every corner to create a cylinder… thus resulting in most of cylinders have
quadruplicates and so making everything slow, specifically the boolean difference…
Just use subdivide surface instead
Here you have many circles, and use the “Area” component to get their centers (which you actually already have! Look few centimeters on the left!) … and then to find the direction of extrusion you “Evaluate Surface” on your circles (so grasshopper will have to cast each and every of your circles to a surface, which will be evaluated to an UV point from the “centroid” aka, a totally random point…)
Centroid point from Area component is a “real” world-space point in absolute XYZ coordinates.
“Point” from Evaluate Surface component is a “UV” point, a “2D” coordinate in the parameter space of the surface. (On a “Reparametrized” surface that space go from 0 to 1 in both direction.)
The only correct way to use this is like this:
But this have to make sense! Is the centroid realling always meaningful for the “center” of your surface? No, not always.
Sometime it’s easier to do something like this:
(notice the reparametrize symbol)
0.5 is “half way” between 0 and 1, but this doesn’t mean exactly half-distance… learn about parametric space in nurbs.
You can speed up things here a bit. I rebuild this whole part of code.
Finally, I’ve added a c# script to do solid difference with custom tolerance, to speed it up.
A3_autosave.gh (89.4 KB)
Good luck!
