It's OK to compare floating-points for equality

New blog post! I really hope I'll get a decent amount of people mad with this one 😈😈😈

#programming #computing #floatingpoint #geometry

lisyarus.github.io/blog/posts/i...

There's already github.com/janestreet/c... and github.com/janestreet/a..., though it looks like the concurrent scheduler and IO library aren't released yet (and both are very wip). Parallel_scheduler also supports concurrency, but it's work-stealing

Also fyi, the compiler doesn't pack record/unboxed product fields yet, small ints still take up a word. Arrays of unboxed numbers are packed, though

Our OxCaml concurrency and IO libraries are getting close to usable - would like to see how writing a web server with them compares :^)

hmm yes we should get around to fixing that

Indexing and array primitives for untagged ints by jra4 · Pull Request #4779 · oxcaml/oxcaml Completes the array and indexing primitives for small integers. In particular, for arrays, strings, bigstrings, bytes: Support storage of int8s, int16#s (including creation of such arrays). Suppor...

Not yet, github.com/oxcaml/oxcam...

🫠https://github.com/oxcaml/oxcaml/pull/5299

@docjade.com 🦀🦀🦀

Holding an OxCaml tutorial at ICFP/SPLASH 2025

Then I dive into the tutorial we held about Oxidised OCaml, the performance-oriented fork at oxcaml.org that @yminsky.bsky.social announced earlier this summer. Try the tutorial in a convenient devcontainer, and take our quiz to help develop the language! @thenumb.at anil.recoil.org/notes/icfp25...

I'll be at ICFP/SPLASH if anyone wants to chat about OxCaml!

And if you’re interested in OxCaml, we have a tutorial on Sunday at ICFP walking through it conf.researchr.org/track/icfp-s... (materials will be online for anyone afterwards. Just the minor detail of finishing writing them first)

wave_tracer 0.1 released
wavetracer.dev

wave_tracer combines path tracing and wave optics in a novel way, for practical general-purpose wave simulations across a variety of EM modalities and applications.

We've seen how to define and apply Monte Carlo integration, but there's a whole world of techniques for reducing variance.
Part five (thenumb.at/QMC) covers Quasi-Monte Carlo: negative correlation, stratified and adaptive sampling, and low-discrepancy sequences.

The Saga of Multicore OCaml YouTube video by Jane Street

I had a lot of fun giving this talk in Singapore about the many-years-long saga of multicore OCaml, and in particular, the work over the least 2.5 years of getting it ready for production work within Jane Street's walls.

www.youtube.com/watch?v=XGGS...

I am getting increasingly excited by the runtime metaprogramming extensions coming into OxCaml. They deal with the fundamental non-portability of most of the modern vector extensions in CPUs (across all architectures), but don't expose any of their decision trees in the interface of the OCaml lib

Our #SIGGRAPH2025 paper "Augmented Vertex Block Descent" presents an extremely fast and stable physics solver with hard constraints for handling joints and collisions.

The project page has a 2D demo with source code and more details:
graphics.cs.utah.edu/research/pro...

There's also the aliased key example in the second tutorial (which already works), but that's not exactly what you want

True but those axes are more restrictive than portability/contention, ie every stateless function is already portable and any value captured at immutable could be captured at contended

There is a way to express shared borrowing, but safely using it in parallel tasks will require support for forking local closures

Rendering nerds! Check out our latest work "Vector-Valued Monte Carlo Integration Using Ratio Control Variates" that has just gotten the best paper award at SIGGRAPH 2025. This paper presents a method that reduces variance of a wide range of rendering and diff. rendering tasks with negligible cost.

We've been working on this for years 📈

I have published my first new blog post in four years lexi-lambda.github.io/blog/2025/05...

Understanding The Math Behind ReSTIR GI Recently, I had the pleasure of contributing to Nvidia’s Zorah project, the flagship demo for the RTX 50 Series GPUs. My primary role was to provide technical support for light transport in Zorah, whi...

Here is a new blog post of mine, where I dive deep into the theory and math behind ReSTIR GI.

Big thanks to Markus Kettunen for verifying the theory, reviewing the article, and catching a key detail I had missed.

agraphicsguynotes.com/posts/unders...

Sobol' Sequences with Guaranteed-Quality 2D Projections, supplementary video YouTube video by Nicolas Bonneel

A thread on Monte Carlo integration, Sobol' sequences and our new awesome Siggraph paper "Sobol' Sequences with Guaranteed-Quality 2D Projections". by @dcoeurjo.bsky.social , J-C Iehl, V. Ostromoukhov and me. The tl;dr is our video: www.youtube.com/watch?v=8A4Z...
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Apologies for the delay of part 5...

Hence we're making it local 🙂

That's what I'm working on for part 5 :^)

Monte Carlo has many uses, but path tracing is one of my favorites. Part four (thenumb.at/Rendering/) explores how Monte Carlo integration is used to simulate light transport.

Monte Carlo methods require randomly sampling complicated domains, which can be difficult in of itself.
Part three (thenumb.at/Sampling/) discusses how to create samplers using rejection, inversion, and changes of coordinates.

Graphics Programming weekly - Issue 386 - April 6th, 2025 www.jendrikillner.com/post/graphic...