X-Ryl669 (u/X-Ryl669)

X-Ryl669 commented on OrthoRoute – GPU-accelerated autorouting for KiCad bbenchoff.github.io/pages... · Posted by u/wanderingjew

X-Ryl669 · a month ago

I don't get why you process the whole connector board at once. If I understand correctly, you're connecting individual & identic boards to your board. So each connector on you giant board is actually dealing a bunch of small board right?

In that case, can't you exploit the inherent symmetry in the design here to only route a quarter of your connectors and then mirror/rotate the result for the other one? Or, if you have a X*X matrix, route one size minus the corners and replicate to the other sides?

Also, with such a huge connection board, it smells a NIH issue here. I think you'd better serialize the IO to a bus (whatever) and few lines and perform the connection in software (in a GoWin FPGA for example, both extremely cheap and quite powerful). Just think of the harness you'll need to build to fit the connectors in. The obvious routing bugs, and so on. Any maintenance will be a nightmare, if you need to swap 2 pins on a connector or re-run the routing.

X-Ryl669 commented on How to stop Linux threads cleanly mazzo.li/posts/stopping-l... · Posted by u/signa11

scottlamb · 2 months ago

This article does a nice job of explaining why pthread cancellation is hopeless.

> If we could know that no signal handler is ran between the flag check and the syscall, then we’d be safe.

If you're willing to write assembly, you can accomplish this without rseq. I got it working many years ago on a bunch of platforms. [1] It's similar to what they did in this article: define a "critical region" between the initial flag check and the actual syscall. If the signal happens here, ensure the instruction pointer gets adjusted in such a way that the syscall is bypassed and EINTR returned immediately. But it doesn't need any special kernel support that's Linux-only and didn't exist at the time, just async signal handlers.

(rseq is a very cool facility, btw, just not necessary for this.)

[1] Here's the Linux/x86_64 syscall wrapper: https://github.com/scottlamb/sigsafe/blob/master/src/x86_64-... and the signal handler: https://github.com/scottlamb/sigsafe/blob/master/src/x86_64-...

X-Ryl669 · 2 months ago

No you can't since the compiler will likely inline the syscall (or vsyscall) in your functions. So there's no way to know the instruction pointer is in the right section. The only way is to pay for no-inline cost and have a wrapper that's calling the syscall, so it's a huge cost to pay for a very rare feature (cancelling a thread abruptly is a no-no in most coding conventions).

X-Ryl669 commented on What's a handy tool for creating/editing Lottie files, free/no watermark? · Posted by u/freitzzz

X-Ryl669 · 3 months ago

I'm using https://glaxnimate.org/ . It's not well known but it's stable and works well for all my needs.

X-Ryl669 commented on Proposal: GUI-first, text-based mechanical CAD inspired by software engineering · Posted by u/thinkmachyx

X-Ryl669 · 5 months ago

FreeCAD files are zip file containing XML documents. There's nothing binary in them, you can modify them by hand if you want. The main issue being that the format itself isn't standardized, so it's continuously evolving, it can't be used as an inter-exchange format. Notice that the last standard revision for STEP files does contains some tools for saving the parametric functions in the file (so the STEP boundary surface description isn't static anymore but can be parametric too). It's not made to save all the possibilities of a huge CAD toolkit, but if such a toolkit wanted to, it could map the functions in the file to its own parametric function and allow skipping a lot of work for recreating the part.