Jakub Vondra
@kubo-von.bsky.social
Senior Environment Artist/TD @ Stim Studio
Toying with Houdini, Gaffer, Cycles.
Working on hobby GPU raytracer in Rust/Metal
@kubo_von@mastodon.gamedev.place
Toying with Houdini, Gaffer, Cycles.
Working on hobby GPU raytracer in Rust/Metal
@kubo_von@mastodon.gamedev.place
toy GPU renderer update:
- DoF / customizable bokeh
- DoF / customizable bokeh
December 16, 2025 at 9:00 PM
toy GPU renderer update:
- DoF / customizable bokeh
- DoF / customizable bokeh
Toy GPU renderer update:
- Nishita sky
- refraction
- VMF Diffuse
- Nishita sky
- refraction
- VMF Diffuse
October 7, 2025 at 9:37 PM
Toy GPU renderer update:
- Nishita sky
- refraction
- VMF Diffuse
- Nishita sky
- refraction
- VMF Diffuse
I find Houdini very useful for prototyping stuff for my toy renderer, here bokeh sampling for example. VEX code is easy to translate to shader code.
September 23, 2025 at 7:19 PM
I find Houdini very useful for prototyping stuff for my toy renderer, here bokeh sampling for example. VEX code is easy to translate to shader code.
Phew, that looks much better. Rogue ggx sampling was making everything glossy, but broken glossy.
September 11, 2025 at 9:58 PM
Phew, that looks much better. Rogue ggx sampling was making everything glossy, but broken glossy.
Having recently acquired a house to fix and an offspring to raise, I have little time. But I've sneaked in some toy renderer time here and there.
Added light MIS, wavelenght importance sampling and really tried improving variance. Battle testing it on scene like this, basically only indirect light.
Added light MIS, wavelenght importance sampling and really tried improving variance. Battle testing it on scene like this, basically only indirect light.
September 10, 2025 at 9:51 PM
Having recently acquired a house to fix and an offspring to raise, I have little time. But I've sneaked in some toy renderer time here and there.
Added light MIS, wavelenght importance sampling and really tried improving variance. Battle testing it on scene like this, basically only indirect light.
Added light MIS, wavelenght importance sampling and really tried improving variance. Battle testing it on scene like this, basically only indirect light.
Toy GPU renderer update
- pathtracing!
- reading basic light and material props from .usd
- basic ggx+lambert shader
- Maya style navigation
#LightTransport #MetalShadingLanguage #RustLang
- pathtracing!
- reading basic light and material props from .usd
- basic ggx+lambert shader
- Maya style navigation
#LightTransport #MetalShadingLanguage #RustLang
June 9, 2025 at 7:03 PM
Toy GPU renderer update
- pathtracing!
- reading basic light and material props from .usd
- basic ggx+lambert shader
- Maya style navigation
#LightTransport #MetalShadingLanguage #RustLang
- pathtracing!
- reading basic light and material props from .usd
- basic ggx+lambert shader
- Maya style navigation
#LightTransport #MetalShadingLanguage #RustLang
February 26, 2025 at 3:43 PM
Toy GPU renderer update:
Might not look like much, trying to get the basics in first.
- sample accumulation ( It flyies so fast on M4 pro! )
- switched from RGB to spectral rendering (hero wavelength / Scott Burns uplift)
- AgX ( a bit broken )
- .exr output
no ray bounces or fancy shading yet
Might not look like much, trying to get the basics in first.
- sample accumulation ( It flyies so fast on M4 pro! )
- switched from RGB to spectral rendering (hero wavelength / Scott Burns uplift)
- AgX ( a bit broken )
- .exr output
no ray bounces or fancy shading yet
February 19, 2025 at 9:22 PM
Toy GPU renderer update:
Might not look like much, trying to get the basics in first.
- sample accumulation ( It flyies so fast on M4 pro! )
- switched from RGB to spectral rendering (hero wavelength / Scott Burns uplift)
- AgX ( a bit broken )
- .exr output
no ray bounces or fancy shading yet
Might not look like much, trying to get the basics in first.
- sample accumulation ( It flyies so fast on M4 pro! )
- switched from RGB to spectral rendering (hero wavelength / Scott Burns uplift)
- AgX ( a bit broken )
- .exr output
no ray bounces or fancy shading yet
I'm trying to implement AgX in Metal shader and hitting a wall, a purple one in this case. 😬
February 18, 2025 at 9:06 PM
I'm trying to implement AgX in Metal shader and hitting a wall, a purple one in this case. 😬
Toy GPU renderer update:
-rays have been fired!
-reading a mesh from an USD file with normals and color using a custom rust wrapper around tinyusdz(c++)
-rays have been fired!
-reading a mesh from an USD file with normals and color using a custom rust wrapper around tinyusdz(c++)
February 3, 2025 at 8:55 PM
Toy GPU renderer update:
-rays have been fired!
-reading a mesh from an USD file with normals and color using a custom rust wrapper around tinyusdz(c++)
-rays have been fired!
-reading a mesh from an USD file with normals and color using a custom rust wrapper around tinyusdz(c++)
More GPU raytracing!
Still just a raytraced triangle, but now rendered from a 3d camera which is controlled by mouse from egui. Also interpolating a primvar there.
Managed to get rid of Metal Kit, it was annoying to use in Rust. Now I'm using egui, it's a breeze to work with and I already know it.
Still just a raytraced triangle, but now rendered from a 3d camera which is controlled by mouse from egui. Also interpolating a primvar there.
Managed to get rid of Metal Kit, it was annoying to use in Rust. Now I'm using egui, it's a breeze to work with and I already know it.
January 23, 2025 at 10:08 PM
More GPU raytracing!
Still just a raytraced triangle, but now rendered from a 3d camera which is controlled by mouse from egui. Also interpolating a primvar there.
Managed to get rid of Metal Kit, it was annoying to use in Rust. Now I'm using egui, it's a breeze to work with and I already know it.
Still just a raytraced triangle, but now rendered from a 3d camera which is controlled by mouse from egui. Also interpolating a primvar there.
Managed to get rid of Metal Kit, it was annoying to use in Rust. Now I'm using egui, it's a breeze to work with and I already know it.
Mom look, I'm raytracing on the GPU!
It took a few evenings, but now I have working Rust + Apple Metal raytracing prototype. Now it's just writing the rest of the renderer.
It took a few evenings, but now I have working Rust + Apple Metal raytracing prototype. Now it's just writing the rest of the renderer.
January 15, 2025 at 9:50 PM
Mom look, I'm raytracing on the GPU!
It took a few evenings, but now I have working Rust + Apple Metal raytracing prototype. Now it's just writing the rest of the renderer.
It took a few evenings, but now I have working Rust + Apple Metal raytracing prototype. Now it's just writing the rest of the renderer.
Giving zbrush one last chance.
January 13, 2025 at 11:11 PM
Giving zbrush one last chance.
I've had this sketch from Ian McQue saved for a very long time, now it's finaly time to give it a go!
Long time since I did a character too.
Started by buying a base mesh from George Zaky and tweaking it in Blender to roughly match proportions.
Long time since I did a character too.
Started by buying a base mesh from George Zaky and tweaking it in Blender to roughly match proportions.
January 13, 2025 at 9:32 PM
I've had this sketch from Ian McQue saved for a very long time, now it's finaly time to give it a go!
Long time since I did a character too.
Started by buying a base mesh from George Zaky and tweaking it in Blender to roughly match proportions.
Long time since I did a character too.
Started by buying a base mesh from George Zaky and tweaking it in Blender to roughly match proportions.
Toy renderer update:
- Pigments - One of the main reason I wanted to do a spectral renderer was the idea of avoiding specifying color in RGB and using something more real-world based.
- Blackbody option for lights.
I need to look into my sampling and seed again to improve the noise.
- Pigments - One of the main reason I wanted to do a spectral renderer was the idea of avoiding specifying color in RGB and using something more real-world based.
- Blackbody option for lights.
I need to look into my sampling and seed again to improve the noise.
December 4, 2024 at 7:24 PM
Toy renderer update:
- Pigments - One of the main reason I wanted to do a spectral renderer was the idea of avoiding specifying color in RGB and using something more real-world based.
- Blackbody option for lights.
I need to look into my sampling and seed again to improve the noise.
- Pigments - One of the main reason I wanted to do a spectral renderer was the idea of avoiding specifying color in RGB and using something more real-world based.
- Blackbody option for lights.
I need to look into my sampling and seed again to improve the noise.
Toy renderer update:
implemented (basically just copy-pasted) EON diffuse model
( arxiv.org/html/2410.18...) without the importance sampling.
left - Lambert, right - EON
model by Henri-Alfred Jacquemart @ threedscans.com
implemented (basically just copy-pasted) EON diffuse model
( arxiv.org/html/2410.18...) without the importance sampling.
left - Lambert, right - EON
model by Henri-Alfred Jacquemart @ threedscans.com
November 27, 2024 at 10:10 PM
Toy renderer update:
implemented (basically just copy-pasted) EON diffuse model
( arxiv.org/html/2410.18...) without the importance sampling.
left - Lambert, right - EON
model by Henri-Alfred Jacquemart @ threedscans.com
implemented (basically just copy-pasted) EON diffuse model
( arxiv.org/html/2410.18...) without the importance sampling.
left - Lambert, right - EON
model by Henri-Alfred Jacquemart @ threedscans.com
Toy renderer update:
- Switched from abusing default USD shaders to MaterialX, definitely not gonna implement all the MtlX nodes though, and I will still need some custom spectral-related nodes.
- Normal maps! I generate tangents in Houdini for now, before I find time to implement MikkT myself.
- Switched from abusing default USD shaders to MaterialX, definitely not gonna implement all the MtlX nodes though, and I will still need some custom spectral-related nodes.
- Normal maps! I generate tangents in Houdini for now, before I find time to implement MikkT myself.
November 22, 2024 at 10:58 PM
Toy renderer update:
- Switched from abusing default USD shaders to MaterialX, definitely not gonna implement all the MtlX nodes though, and I will still need some custom spectral-related nodes.
- Normal maps! I generate tangents in Houdini for now, before I find time to implement MikkT myself.
- Switched from abusing default USD shaders to MaterialX, definitely not gonna implement all the MtlX nodes though, and I will still need some custom spectral-related nodes.
- Normal maps! I generate tangents in Houdini for now, before I find time to implement MikkT myself.
Anyone else debugs mainly like this ?
November 16, 2024 at 8:21 PM
Anyone else debugs mainly like this ?
Some recent updates to my toy renderer:
- Rewrote BSDF sampling
- Textures! (tiled and with mip-making using custom tx make util)
- shadow rays not trasmitt through non-opaque objects
I think i'll start post more here now, in case it's finally the death of X.
- Rewrote BSDF sampling
- Textures! (tiled and with mip-making using custom tx make util)
- shadow rays not trasmitt through non-opaque objects
I think i'll start post more here now, in case it's finally the death of X.
October 17, 2024 at 11:34 AM
Some recent updates to my toy renderer:
- Rewrote BSDF sampling
- Textures! (tiled and with mip-making using custom tx make util)
- shadow rays not trasmitt through non-opaque objects
I think i'll start post more here now, in case it's finally the death of X.
- Rewrote BSDF sampling
- Textures! (tiled and with mip-making using custom tx make util)
- shadow rays not trasmitt through non-opaque objects
I think i'll start post more here now, in case it's finally the death of X.
November 10, 2023 at 6:51 PM
What started as a quick debug Egui widget for my toy renderer expanded into writing a weird 3d viewport It's just 2d lines draw based on projected 3d data, performance not great, but could be enough for some usage.
github.com/kubo-von/egu...
github.com/kubo-von/egu...
October 13, 2023 at 8:35 AM
What started as a quick debug Egui widget for my toy renderer expanded into writing a weird 3d viewport It's just 2d lines draw based on projected 3d data, performance not great, but could be enough for some usage.
github.com/kubo-von/egu...
github.com/kubo-von/egu...
=Toy renderer update=
Re-implemented random walk SSS. All is still noisy and slow but it's fun to be working on it again.
Re-implemented random walk SSS. All is still noisy and slow but it's fun to be working on it again.
September 21, 2023 at 10:53 PM
=Toy renderer update=
Re-implemented random walk SSS. All is still noisy and slow but it's fun to be working on it again.
Re-implemented random walk SSS. All is still noisy and slow but it's fun to be working on it again.
=Toy renderer update=
Finally somewhat cracked refraction! Not sure if it's correct, but at least I can move on to other stuff, like all that noise for example.
#lighttransport
Finally somewhat cracked refraction! Not sure if it's correct, but at least I can move on to other stuff, like all that noise for example.
#lighttransport
September 14, 2023 at 10:11 PM
=Toy renderer update=
Finally somewhat cracked refraction! Not sure if it's correct, but at least I can move on to other stuff, like all that noise for example.
#lighttransport
Finally somewhat cracked refraction! Not sure if it's correct, but at least I can move on to other stuff, like all that noise for example.
#lighttransport