Hacker News: pierrec

New comment by pierrec in "Hengefinder: Finding when the sun aligns with your street"

pierrec — Sat, 23 May 2026 18:58:20 +0000

Interesting, I've planned similar shots before and used different tools that serve a similar purpose. The Photographer’s Ephemeris has nice visualizations: https://photoephemeris.com/

NASA's Horizons ephemeris is also pretty good at preparing data for this. I've used it with a little script to check when the sun/moon will be in a given box. This hengefinder looks neat and really streamlined for its purpose though.

New comment by pierrec in "Cannibalistic attacks between gray seals leave telltale “corkscrew” injuries"

pierrec — Mon, 18 May 2026 03:54:26 +0000

Oddly enough, I've seen a similar injury on a dolphin before. Well, the head was missing, but the cutoff point could be described as "corkscrew". None of us had a good idea of the cause, but this hints it may have been predation or scavenging.

New comment by pierrec in "Virtual violin produces realistic sounds"

pierrec — Wed, 06 May 2026 19:57:15 +0000

Fair point, my (and many people's) point of view is very virtual instrument centric. I'd still say that better impulses would improve the tool for the potential luthier application.

New comment by pierrec in "Virtual violin produces realistic sounds"

pierrec — Wed, 06 May 2026 16:09:34 +0000

In this area of research, there's this classic trap that many fall into (including myself, many times). You focus on modeling things like the vibrating string, the resonant body, etc. to perfection. But it still sounds, uh, not great, because the more important and difficult part is modeling detailed control and the human/instrument interface. Air fluctuations around the violin sound like a fun experiment, but I don't think you'll get much additional realism from that, compared to a simple/classical impulse response model.

Even in this case, they're choosing the easy path (plucked, pizzicato), but the human/instrument interface is still audibly oversimplified while the resonant body has an unnecessary amount of "realism". The sound of pizzicato has a distinct character because the player's finger/skin slides a bit on the string as they're plucking, among other factors, which sounds like it's missing here. This can be tricky to implement because it's not necessarily a one-way impulse. The string is already vibrating and affects the finger, hence "interface".

This applies 10x more with bowed strings.

New comment by pierrec in "I gave every train in New York an instrument"

pierrec — Sun, 12 Apr 2026 18:17:25 +0000

The music all by itself is not particularly enjoyable here. What's great is the concept, execution, and the way data from an unlikely source is directly audible in the music. What defines art will always be fuzzy, but this particular work is a good example of art I can appreciate: presenting known things in an unusual way, playing with perception to create new connections between remote concepts, and sometimes providing a stepping stone to, as you say, enlightenment.

New comment by pierrec in "Generative art over the years"

pierrec — Fri, 10 Apr 2026 05:18:20 +0000

Generative art inspired by Arabic art happens to be a rabbit hole I went down last year and still have my notes on. Research on the topic seems to have waxed and waned sufficiently long ago that the best resources I found have suffered from bit rot, thankfully much of it can still be accessed through the Internet Archive:

https://web.archive.org/web/20140701114342/http://www.cgl.uw...

https://web.archive.org/web/20180426122308/http://www.wozzec...

Of course the topic is still alive to some extent, but the above 2 "dead" homepages remain some of the best entry points I've found overall.

New comment by pierrec in "Lunar Flyby"

pierrec — Wed, 08 Apr 2026 18:07:52 +0000

They are not shy about publishing LRO data. It looks like this (one for each LRO camera, narrow angle then wide angle):

https://data.lroc.im-ldi.com/lroc/view_lroc/LRO-L-LROC-2-EDR...

Feel free to assemble these into nice composites or 3D renders.

New comment by pierrec in "Revision Demoparty 2026: Razor1911 [video]"

pierrec — Wed, 08 Apr 2026 14:52:18 +0000

The parts where it exits fullscreen and starts messing around with separate windows is really well done. In a way it's playing with the limits of what defines a demo (ie. the user's desktop is part of the performance), which is something I love to see. Same with the notepad animation part. I wonder if they implemented their own notepad-alike from scratch or it they used something like this: https://kylehalladay.com/blog/2020/05/20/Rendering-With-Note...

New comment by pierrec in "Artemis II crew see first glimpse of far side of Moon [video]"

pierrec — Sun, 05 Apr 2026 16:45:31 +0000

>they haven’t adjusted course to go round the far side of the moon yet

They did, 3 days ago! Maybe this is being pedantic (?) but the trans-lunar injection burn they did on April 2 put them on the complete trajectory including return to Earth. Though there are still possible correction burns that can be done to increase precision (the first 2 of these were already canceled).

New comment by pierrec in ""Roadrunner": a bipedal, wheeled robot for multi-modal locomotion [video]"

pierrec — Mon, 30 Mar 2026 13:39:42 +0000

I could ask you the same question.

New comment by pierrec in "How and why to take a logarithm of an image [video]"

pierrec — Fri, 27 Mar 2026 20:50:31 +0000

Though since we can't really see 3D, we could never have that "one circle zooms in" effect.

Well, the 3D structure just needs to be sufficiently "holey" for the effect to become apparent. For example a cage-like structure, or a house with no roof (when seen from above).

New comment by pierrec in "How and why to take a logarithm of an image [video]"

pierrec — Fri, 27 Mar 2026 15:57:58 +0000

This kind of technique can be used in 3D space as well! The analysis here represents Escher's techniques as conformal maps in the complex plane. Conformal maps are also possible, though more limited, in R^3. This is something that I explored some years ago and wrote an article about it, though it focuses more on graphics than math: https://www.osar.fr/notes/logspherical/

New comment by pierrec in "Chest Fridge (2009)"

pierrec — Sun, 22 Mar 2026 05:09:35 +0000

Now that is the coolest fridge I've ever seen. Found a video of it in action (yes, featuring the same dad joke all over the comments but that is not stopping me): https://youtu.be/RoGuvvzHY1A?t=416

That entire place is mind-bending.

New comment by pierrec in "Building a TB-303 from Scratch"

pierrec — Wed, 11 Mar 2026 17:15:23 +0000

The plugin in that demo isn't by Jeskola, it's by HD (Haldreamer) who I believe is a Russian audio developer who made some nice Buzz plugins in the early 2000's. Source: I have it installed and I just checked the "about" box.

New comment by pierrec in "Earth Garden: Field Recordings Around the World"

pierrec — Thu, 05 Mar 2026 15:00:13 +0000

If what you want is the sounds of nature around the world, I can't recommend Gordon Hampton's work enough!

New comment by pierrec in "The Xkcd thing, now interactive"

pierrec — Wed, 04 Mar 2026 01:33:42 +0000

Come on, HN, you can't let this information stay under the front page for 13 hours and everyone's like "ah yes of course". Please don't register the mousemove event handler on window, that old school hack never really worked and was obsoleted 10 years ago when the pointer API became standard.

Things are much nicer now and the problem is entirely avoided by using pointer events: https://developer.mozilla.org/en-US/docs/Web/API/Element/set...

New comment by pierrec in "Elvish as She Is Spoke [pdf]"

pierrec — Wed, 18 Feb 2026 15:58:38 +0000

For some context, the author later became the language consultant for Rings of Power, therefore having to fill a very similar role to David Salo, whose work gets much critique in this essay. Makes you wonder if the ideal of "don't translate English to Elvish" was preserved when faced with the reality of the series production.

New comment by pierrec in "The three year myth"

pierrec — Sat, 14 Feb 2026 09:20:22 +0000

I love this and will make it my motto. Scale yourself 100x every 3 years, or you're too slow. If I manage to keep it up roughly 11 years I will finally achieve planet scale.

New comment by pierrec in "Skip the Tips: A game to select "No Tip" but dark patterns try to stop you"

pierrec — Fri, 13 Feb 2026 03:48:01 +0000

OK, I sent the email myself. You don't have to do it. Just once, not 5 times per day. Agree about community awareness, but I think emailing the mods is more effective than responding to one of the 1000 comments this account is making.

New comment by pierrec in "Skip the Tips: A game to select "No Tip" but dark patterns try to stop you"

pierrec — Fri, 13 Feb 2026 03:36:24 +0000

I would suggest sending this as an email to the mods instead of a reply, what you're doing is practically a bug report to the bot owner right now. The resulting discussion isn't super interesting either (IMO).