15:06 <invultri> Hi, a quick question about the docs on polygon. It states: "multiple vectors

15:06 <invultri> Creates primary and secondary shapes. Secondary shapes are subtracted from the primary shape (like difference()). Secondary shapes may be wholly or partially within the primary shape." But it seems that it only removes the overlaps and does show the remainder of the 'hole' polygon. Difference does something quite different. Is the doc 'wrong' here

15:06 <invultri> or am I doing something wrong?

15:07 <invultri> https://gist.github.com/christianvdstap/74945b4a5d9f856a956876fbfa35ef81

15:33 <invultri> I also notice I could probably just use difference straight away with this setup. Which fixed the issue, thanks for helping.

18:09 <ndnihil> is the source for this posted somewhere? I consulted the mighty (G)oracle and looked through the github, but didn't see it: https://en.wikibooks.org/wiki/File:Spring_100x20_in_OpenSCAD.gif

18:37 <InPhase> ndnihil: Not that I know of, but it's easy enough to replicate: https://bpa.st/LHY7K

18:54 <ndnihil> thanks, I'll poke around that

19:01 <J23k27> not ideal to have an example that is clearly not just a linear extrusion (or at least with some additional profile calculation)

19:08 <ndnihil> it was just my up/down animation thing that was broken

19:08 <ndnihil> figured I'd see how other people do it

19:09 <ndnihil> turns out it's much the same, when you dont fuck up the math part

19:49 <InPhase> J23k27: The spring thing is a nice illustration of what OpenSCAD should be good for, it just happens that that exact structure of spring does not line up well with what the built-in tools do well.

19:51 <InPhase> Really what we need is for rotate_extrude to have an optional flag for a height change so it can helically spiral up like that.

19:59 <J23k27> yeah i rooting for "pitch" for years - Ü

19:59 <J23k27> all those wormgears and threads would benefit

20:00 <J23k27> it sure can cause intersections .. but we already have this when something is on - and + x

20:03 <J23k27> and twist would be fun too

20:04 <J23k27> oh and scale