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Re:Show HN: 3D Meshes of Signed Distance Functions in Python by bvrmn on Wednesday February 17, 2021 @06:00AM (#26165042)
OpenSCAD is pretty rigorous regarding defining relative geometry. Like shifting origin and sketch on plane rotated 30° around X. It leads to unnecessary math to place objects.
Re:Show HN: 3D Meshes of Signed Distance Functions in Python by alpaca128 on Wednesday February 17, 2021 @06:13AM (#26165134)
It can be a bit cumbersome sometimes, but the only thing that really slows me down is the rendering performance. As soon as the detail level exceeds a certain range it basically becomes a bottleneck the size of a singularity.

Just the last few days I spent hours creating an external preprocessor for a project so I can feed as little data as necessary into OpenSCAD. Luckily it kind of worked and got me from "process gets killed after 70 minutes" down to "finished rendering in 5 minutes".

Still it's my favorite CAD software because the coding paradigm just feels so much more intuitive and simple than what FreeCAD and others do.

I'm definitely going to try out this project, though; it looks very promising as well.

Re:Show HN: 3D Meshes of Signed Distance Functions in Python by sitkack on Wednesday February 17, 2021 @10:09AM (#26167119)
(to the channel), I am sure you know about it, but this [1] technique for making a big design a tree of smaller designs works ok.

I feel like OpenSCAD is like 2 standard deviations away from perfection. Functions vs Modules and how clunky composition and application of operators over the object tree. It almost needs to be Datalog. Right now, it is a notch under SQL.

[1] https://old.reddit.com/r/openscad/comments/lbq58y/my_approac...

Re:Show HN: 3D Meshes of Signed Distance Functions in Python by alpaca128 on Wednesday February 17, 2021 @01:50PM (#26169972)
The problem in my case was that I wanted to combine a pattern with my objects that I precomputed using an external program because it contained a lot of curved surfaces. As I already knew OpenSCAD basically becomes unusable if you try to use a png image as heightmap I decided to instead generate a .scad file containing an array with precomputed coordinates, and then used that to build and extrude 2d polygons.

This kind of works for the 3d preview, but the stl renderer was not happy regardless. It was basically the worst case for OpenSCAD. But still, the fact I could just auto-generate a text file and use it directly for building models is fantastic. With tools like FreeCAD I wouldn't even know where to start, here it was basically a case of "it just works" and with a few more minutes it can be combined with a bash script for batch rendering.

Re:Show HN: 3D Meshes of Signed Distance Functions in Python by blt on Wednesday February 17, 2021 @01:59PM (#26170081)
Isn't this par for the course for constructive methods though? I agree that some things that are easy in a classic constraint-based CAD package are a huge burden in OpenSCAD. However, I don't see how signed distance fields would change that.