Lionel Lemarié
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hikey.org
Lionel Lemarié
@hikey.org
Rendering, ray tracing, Metal API.
Reposted by Lionel Lemarié
New blog post! (yep, at New Year's Eve.) A short detour into a fun one-liner shading model I use for clouds in my game 🥰

lisyarus.github.io/blog/posts/a...
December 31, 2025 at 3:03 PM
Reposted by Lionel Lemarié
New post! "Realtime Raytracing in Bevy 0.18 (Solari)"

jms55.github.io/posts/2025-1...
December 27, 2025 at 8:51 PM
Reposted by Lionel Lemarié
My "No Graphics API" blog post is live! Please repost :)
www.sebastianaaltonen.com/blog/no-grap...

I spend 1.5 years doing this. Full rewrite last summer and another partial rewrite last month. As Hemingway said: "First draft of everything is always shit".
No Graphics API — Sebastian Aaltonen
Graphics APIs and shader languages have significantly increased in complexity over the past decade. It’s time to start discussing how to strip down the abstractions to simplify development, improve pe...
www.sebastianaaltonen.com
December 16, 2025 at 6:52 PM
Cem Yuksel's update to the teapot model looks great with a glass material!
#metalrt #rendering
December 12, 2025 at 2:37 PM
Reposted by Lionel Lemarié
A modernized Utah Teapot model with interior! You can see/customize/download it, along with historical versions on the official teapot page:
graphics.cs.utah.edu/teapot/
December 11, 2025 at 5:34 AM
Reposted by Lionel Lemarié
After nine years of development, meshoptimizer has reached its first major version, 1.0!

This release focuses on improvements in clusterization and simplification as well as stabilization. Here's a release announcement with more details on past, present and future; please RT!

meshoptimizer.org/v1
🐇 meshoptimizer v1.0
Mesh optimization library that makes meshes smaller and faster to render
meshoptimizer.org
December 8, 2025 at 4:56 PM
Naive attempt at loading the Zorah scene. Uses 200GB of RAM. With enough swap and patience, who needs optimization?..
#metalrt #rendering
December 10, 2025 at 3:45 AM
Zorah looks like a nice level-up if you've conquered the classic Swallowing the Elephant challenge!
(pharr.org/matt/blog/20...)
October 2, 2025 at 2:26 PM
Reposted by Lionel Lemarié
Some images showing off my improvements to my photon mapper I have integrated into truetrace
The photon mapper is up on the Dev branch on the github
September 21, 2025 at 8:29 PM
Reposted by Lionel Lemarié
My latest coding adventure is now up on YT -- some experiments with ray-tracing glass and water, and the cool caustics they can cause
youtu.be/wA1KVZ1eOuA?...
Coding Adventure: Ray-Traced Glass and Caustics
YouTube video by Sebastian Lague
youtu.be
August 16, 2025 at 12:44 PM
Reposted by Lionel Lemarié
Experimenting with a face extrusion and retraction brush in my toy #voxel editor. Threw a bit of #raytracing in there while I was at it ✨
August 4, 2025 at 7:28 PM
Got an MRI so I played with some renders of the inside of my melon.
#metalrt #rendering
July 19, 2025 at 8:21 PM
Morphing fractal shapes.

This is a Julia fractal with a linear interpolation of the distance function between iteration counts. Starts by interpolating between 1 and 3 iterations, then 3 and 5, etc...
The material also changes for no particular reason...

#metalrt #rendering #fractal
July 15, 2025 at 12:31 PM
Reposted by Lionel Lemarié
New on Metal by Example: Getting Started with Metal 4, a breezy introduction to the fundamental changes arriving in the Metal API later this year: metalbyexample.com/metal-4/
Getting Started with Metal 4
Another WWDC is in the books, and with it came a major update to many platform technologies, including Metal. Metal graduated to version number 4, and in this article, we’ll explore the core …
metalbyexample.com
July 8, 2025 at 10:46 PM
🧵 Attempting to render a rainbow simply by path tracing millions of rain drops. It's not working well yet...

Starting by looking closely at a drop and going through the color spectrum, we can see the diffraction at play: the refracted scene appears to move due to the changing ior.
July 7, 2025 at 5:38 AM
Fractal SDF rendered as voxel spheres.
The high resolution one has close to 1 billion spheres.
#metalrt #rendering
July 5, 2025 at 11:27 PM
July 5, 2025 at 1:11 AM
July 5, 2025 at 1:09 AM
@jbakergraphics.bsky.social has an amazing collection of fractal distance estimators! jbaker.graphics/writings/DEC...
All the authors are listed on the page. There are some gems in there!
#metalrt #rendering
July 4, 2025 at 7:32 AM
Renders of an old scene by Maximilian Tarpini. Makes for a fun light study.
#metalrt #rendering
July 2, 2025 at 1:12 PM
I got a pico-mac-nano! Such a cool little device. The 1.5" screen looks awesome.
When I was a kid playing on my parents' Mac Plus and read that computers could one day fit in your pocket - *this* is what I imagined it would look like.

blog.1bitrainbow.com/pico-mac-nano/
July 2, 2025 at 12:26 AM
Quick test of participating medium - simplest possible: on primary rays, N% chance of bouncing in a random direction at an arbitrary point between the origin and the intersection.

Not a bad result, but I'm disappointed not to see better refracted light trails under the sphere.

#metalrt #rendering
July 1, 2025 at 12:22 AM
Gotta love the amount of detail available in the OSM maps.
#metalrt #rendering
June 30, 2025 at 3:54 AM
Nice little palate cleanser for my mind: easy renders of a few landmarks using OSM data.
Some of these are 100M triangles. Plenty of detail in there.
#metalrt #rendering
June 30, 2025 at 1:02 AM
The photon debugging view is working pretty well now. I can navigate the scene to look at the paths, bounces and final photon positions - along with a preview of their impact on the scene.
#metalrt #rendering
June 28, 2025 at 6:27 PM