Lionel Lemarié
banner
hikey.org
Lionel Lemarié
@hikey.org
Rendering, ray tracing, Metal API.
It's so close to perfect!
July 22, 2025 at 12:58 PM
July 20, 2025 at 7:53 PM
July 20, 2025 at 12:46 PM
July 20, 2025 at 12:42 PM
July 19, 2025 at 11:14 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
Thanks for the great recommendation! I got one and it was amazing (:
July 17, 2025 at 2:27 AM
Glass fractals.
July 16, 2025 at 3:08 AM
July 16, 2025 at 12:58 AM
July 15, 2025 at 9:32 PM
Another view of the same scene.
July 15, 2025 at 5:59 PM
Another render. This one also transitions between fractal powers (squared to cubed).
#fractal
July 15, 2025 at 12:34 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
Added another debug tool: explicit support for rainbows. Showing what it may look like if I ever got the physically based drops to work...
This is using an explicit check on each ray for the angle against the light direction and add color to the pixel accordingly for the main and secondary arcs.
July 13, 2025 at 7:37 PM
I tried a quick animation, but again it's missing a big part without the caustics. This is moving the income ray very slightly left and right.
July 11, 2025 at 1:04 PM
Nice one! Those are gorgeous. Great concept.
I had a go at making a similar scene - but without the nice caustic effect it's not nearly as impactful.
July 11, 2025 at 5:52 AM
Close up on the drops to see the bounces.
July 10, 2025 at 3:34 PM
Fly-through for better context.
July 10, 2025 at 3:05 PM
Another debug scene to try and understand rainbows a little better. This is tracing the rays coming from the sun, bouncing inside "drops" (glass spheres) and reaching the eye of the lad looking up.
July 10, 2025 at 3:03 PM
I also had a go at displaying LAS and PLY point clouds as spheres. They can look quite nice.
July 9, 2025 at 12:47 PM
The point of precomputing was mainly for cellular automata and wave function collapse. I had some fun shapes with those.
July 9, 2025 at 5:09 AM
I have some old code that I'll dig out. It worked really well, but at the time I supported a single grid per scene. This time I'll make it a primitive so I can have many.
I was using it for weird renders like this. The packing is pretty efficient: as low as 1bit per cell, or 0 if not precomputed.
July 9, 2025 at 5:06 AM
The rainbow is still elusive...
But how about subsurface scattering the hard way? By rendering tiny diffuse particles (atoms?) to simulate the many internal bounces of the surface.
Looks a little bit like sugar.
July 9, 2025 at 2:15 AM
Progress: there's a bit of rainbow!
July 8, 2025 at 5:00 PM
360º view and still no rainbows... I know it's in there somewhere. I just have to find it.
July 8, 2025 at 4:35 PM