Raph Levien

I do fundamental research on 2D graphics, UI programming, and fonts, and am active in the Rust community. 🌈

Website: https://levien.com/
Blog: https://raphlinus.github.io/
GitHub: https://github.com/raphlinus

Last Notes

2026-08-09 23:29:09 GMT

I just posted a blog post on my hyperbezier curve: https://linebender.org/blog/hyperbezier/
I've actually been working on this for years, and only recently figured out a solution to the parameter mapping problem. I think this curve is potentially better than cubic Béziers for 2D vector graphic design. It is smoother but has the same useful expressive range.
https://files.mastodon.online/media_attachments/files/117/068/155/820/656/211/original/326084e32f6a54d3.png

2025-12-31 17:32:05 GMT

Does anyone in the Bay Area want some historical computer books? Includes K&R, Wirth's book on Pascal, HOPL 1, PostScript, IBM 1401, some computer music stuff, some logic. Pick up in Berkeley. Otherwise it gets dumped.

2025-12-11 18:14:22 GMT

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Yes, so glad I left.

2025-07-04 14:16:21 GMT

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I was more upset by this than I thought I would be. And I think the damage is enormous. Until yesterday, getting an email from the Social Security Administration was a trusted source of information, relied upon by many people who really need that.
I reported it as spam and unsubscribed, as I do with all unsolicited campaign ads.

2024-10-07 16:24:44 GMT

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Apparently notices went out but Geico is cleaning it up. See the update at https://jalopnik.com/geico-is-cancelling-tesla-cybertruck-policies-as-it-doe-1851666570

2024-09-03 14:12:04 GMT

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I am happy to write it up if you like, but Ivan has it, except that int64(u) not a float-to-int case, it's an unsigned-to-signed cast.
I've been doing quite a bit of low level bit magic in my sparse strip GPU path rendering implementation. That really needs a writeup!

2024-09-03 01:32:44 GMT

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I think you can save one instruction by doing:
mask := uint64((int64(u) >> 63)) | (1 << 63)
In my godbolt, this compiles as an arithmetic right shift as opposed to a logical right shift followed by negation.