when i did openscad, i just did a minowski hull with a 4sided bipyramid (aka rotated cube) to get chamfers for my cubes.
bonus: minowski hull with a round pyramid adds chamfers in the vertical and fillets in the horizontal, which is what i want for 3d printing most of the time. additionally it closes small overhangs, and it makes fonts smoother (i.e. fonts don't extrude in a 90degree angle, and get 45degree instead, and print better on vertical faces)
disclaimer: I havent used openscad for about a year and my memory may be fuzzy
edit: i am not saying minowsky hull would directly solve your problem, but maybe the algorithm gives you inspiration to solve your numerical issues
OpenSCAD is mesh based so it's not even in the same universe as a proper brep geometric kernel. Everything is easier when you give up on the math entirely, but that’s not good enough for real world manufacturing and simulation.
All of the major commercial geometric kernels have been working on these problems for thirty years and I’m sorry, but your five minutes experience with a glorified tessellator isn’t going to make progress on long standing computational geometry problems.
>that’s not good enough for real world manufacturing and simulation
Dumb question: why not?? It's working for that guy and his 3D printer apparently, which is "real world" (though one could certainly argue it's not proper "manufacturing").
In theory pi has infinite places, sure . In real-world practice (vs math-lympics) you never need more than 100 digits, and indeed you rarely ever actually need more than 5.
Why doesn't it work to "just" throw more bit-width and more polygons at it? Who out there actually needs more than that (vs who just thinks they do)?
The answer boils down to “floating point math” and “discontinuities”.
> indeed you rarely ever actually need more than 5.
That’s not how math works. With every operation the precision falls, and with floats the errors accumulate. What was five digits quickly becomes 3 digits and now you’ve got three surfaces that are supposed to, but don’t technically intersect because their compounding errors don’t overlap even though the equations that describe them are analytically exact. Modern geometric kernels have 3 to 7 tolerance expansion steps that basically brute force this issue when push comes to shove.
Once you have these discontinuities, a lot of critical math like finite element modeling completely breaks down. The math fundamentally depends on continuous functions. Like I mentioned above, three corner filets create a singularity in parametric space by default, so even the core algorithms that kernels depend on to evaluate surfaces break on a regular basis on basic every-day operations (like a box with smoothed edges - aka almost every enclosure in existence)
> Who out there actually needs more than that (vs who just thinks they do)?
I can’t stress this enough: almost everyone. CAD isn’t one of those fields where you can half ass it. Even the simplest operations are bound to create pathological and degenerate cases that have to be handled, otherwise you have a pile of useless garbage instead of a 3d model.
Slicers deal with meshes, like video game renderers, not boundary representations like CAD kernels. There is effectively zero overlap. Even just tessellation, the step that converts brep to mesh, is significantly harder than anything 3d printing software has to do.
> I don't think open source can get a big market share but it can give you a nice niche market of tech enthusiasts
companies and governments in Europe start embracing digital sovereignty. Governments start to realize, that US corporations lie, when they say they won't spy on governments officials.
I am not saying, that Europe WILL increase opensource and sovereignty, but odds are good, that a cultural shift away from US-dependence will happen soon, which would include embracing of Opensource
did you have issues with banking apps, authenticator apps or outlook on workprofile?
I ask, because when I was using cyanogenmod a hundred years ago, banking apps were a major pain. And now I am using outlook on a flagship with stockrom, and outlook on workprofile is still a major pain, and I can easily imagine, it working even worse on grapheneos.
I don't have outlook, but Teams works normally, as far as I can tell
> authenticator apps
No issues there with the Microsoft Authenticator and Yubico Authenticator.
> banking apps
My banking apps work, but that's not the case for all of them. I would personally change bank rather than leaving GrapheneOS. The annoying part could be work apps (I wouldn't want to have a second phone just for work), but my bank I can change :-).
I selfhost for >10 years, but only for receiving, i.e. I can not send anything from my domain, because I thought that would have been to much stress to set up.
My setup: I have a root server with DNS attached to it. On there is a postfix, with a minimal config that forwards all emails to my real address on posteo.eu. And posteo has not given me any trouble with any of my emails at all.
I use this setup, so I can easily give new email-addresses to individual web services, and it gives me the option to selectively block these addresses.
Last year I brought the big abo from proton, which includes throwaway mailadresses, and I am thinking about migrating my mail setup there.
> No one buys a Porsche because they want a sensible car for their family or they need something with large storage
I know two porsche-owners personally. One sometimes uses his porsche (non SUV, but the small fast one) to go on family vacations (with the kids cramped at the too small back seats, which seems funny to me). The other has an SUV and lives in the country with bad roads; They sometimes use their porsche to commute to work and for everyday-stuff like shopping.
> The other has an SUV and lives in the country with bad roads; They sometimes use their porsche to commute to work and for everyday-stuff like shopping.
That blows my mind.
I guess its the same mindset as people who buy a mercedes "jeep" (don't know the product id) or range rover and live the middle of the city.
They kind of spoke to it. Rebasing to bring in changes from main to a feature branch which is a bit longer running keeps all your changes together.
All the commits for your feature get popped on top the commits you brought in from main. When you are putting together your PR you can more easily squash your commits together and fix up your commit history before putting it out for review.
It is a preference thing for sure but I fall into the atomic, self contained, commits camp and rebase workflows make that much cleaner in my opinion. I have worked with both on large teams and I like rebase more but each have their own tradeoffs
Yes but specifically with a rebase merge the commits aren’t interleaved with the commits brought in from mainline like they are with a merge commit.
EDIT: I may have read more into GPs post but on teams that I have been on that used merge commits we did this flow as well where we merged from main before a PR. Resolving conflicts in the feature branch. So that workflow isn’t unique to using rebase.
But using rebase to do this lets you later more easily rewrite history to cleanup the commits for the feature development.
You'll still get interleaved commits. If I work on a branch for a week, committing daily and merging daily from main, when I merge to main, git log will show one commit of mine, then 3 from someone else, then another of mine, etc. The real history of the main branch is that all my commits went in at the same time, after seven days, even if some of them were much older. Rebase tells the real story in this case, merge does not.
That's because the unannounced firedrills don't involve setting the building on fire. A "drill" equivalent would be if we all pretended the internet is down sometimes, and in some cases that still might be impossible to do without negative consequences.
bonus: minowski hull with a round pyramid adds chamfers in the vertical and fillets in the horizontal, which is what i want for 3d printing most of the time. additionally it closes small overhangs, and it makes fonts smoother (i.e. fonts don't extrude in a 90degree angle, and get 45degree instead, and print better on vertical faces)
disclaimer: I havent used openscad for about a year and my memory may be fuzzy
edit: i am not saying minowsky hull would directly solve your problem, but maybe the algorithm gives you inspiration to solve your numerical issues
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