Hi PaQ, thanks for the very clear repro steps!

After a couple of tries (seems sensitive to the position of the box) I could repeat it over here with the Sep-21 beta, and got it saved off to a file where I can reproduce it.

But it does not happen with v1 or with my current working build, I think that probably it is the same bug as that "broken fillet corner" problem that you posted previously, but I'm going to do some testing to verify that.

- Michael

Hi PaQ, I followed the procedure exactly and I could not replicate your problem, do you delete the left over pieces before the Boolean operation or just hide them ?

Just out of curiosity PaQ, what's the reason that you use Boolean merge in that situation, I tend to use Boolean Diff when splitting solids with a line.

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Happy that Michael was able to reproduce it, it's indeed a strange one, probably scaling and the box position like Michael said, is important too.

@Danny : the left part is deleted

>> Just out of curiosity PaQ, what's the reason that you use Boolean merge in that situation, I tend to use Boolean Diff when splitting solids with a line.

Because I didn't know that the boolean difference will work too :)

> Because I didn't know that the boolean difference will work too :)

They will both give the same result for this kind of case.

- Michael

Hi PaQ, turns out this was actually a separate bug from that fillet one, but it was also one that I happened to fix already for the next beta.

It was a regression in that geometry library that happened back a couple of betas ago, involving trimming sphere surfaces.

The way the bug happened, it actually did not cause a problem in the boolean calculation itself though, but in the tessellator. So that problem there is actually a messed up display mesh, not actually messed up geometry.

At any rate, it is all fixed up for the next beta.

I'm not surprised that it took until about now to work some of the kinks out of the geometry library update, that actually went a lot smoother than I had worried it might.

Thanks very much for gathering up the bug report!

- Michael

Thanks for the update !