Karl
LightNews LightNews
banner
hexaquo.at
Karl
@hexaquo.at
1.3K followers 950 following 210 posts
Researcher, teacher and activist somewhere at the intersection of landscape perception, graphics programming, open source, and climate change.

Working on VR landscape visualization with Godot. Maintaining Geodot: https://github.com/boku-ilen/geodot-plugin
Posts Replies Media Videos
Reposted by Karl
jendrikillner.bsky.social
Graphics Programming weekly - Issue 423 - January 11th, 2026 www.jendrikillner.com/post/graphic...
January 15, 2026 at 3:11 PM
Reposted by Karl
hikey.org
Fractal mitosis 3.
#metalrt #rendering
January 14, 2026 at 5:00 PM
hexaquo.at
#godot #gamedev
Screenshot of a landscape rendered in Godot. View into a hilly landscape from a field track next to a sunflower field, with a small tree in the middle. The sun is fairly low. View up into the sky with a branch in the foreground and another tree in the distance. The sun is visible and creates some slight lens flares. View into the distance onto an expansive, slightly hilly landscape, with different agricultural fields. A few birds are flying in the distance. View over a field onto a village. The sun is low, creating a golden light.
January 13, 2026 at 3:24 PM
hexaquo.at
#godot #gamedev
January 8, 2026 at 12:28 PM
hexaquo.at
Lens Flare update: exposed all configurable parameters now. There's probably still a lot of potential for performance optimization, but I'd say it's somewhat usable :)

You can check it out here, should work in any project (though requires some HDR care):
github.com/kb173/godot-...

#Godot #gamedev
December 29, 2025 at 2:30 PM
Reposted by Karl
lauriewired.bsky.social
Gaussian splats are quite the rage lately (for good reason).

Yet the technique is actually quite old!


35 years ago, Lee Westover created the worlds first splat with the “UNC Head” dataset.

A high-res CT scan...much too detailed for computers at the time.
December 23, 2025 at 8:27 PM
Reposted by Karl
quest64official.bsky.social
December 25, 2025 at 11:06 PM
hexaquo.at
If you want your #Godot game to look like Battlefield 3, I got you
Screenshot of a Godot scene with a blue sky and the sun visible through a large window in a concrete structure. The sun (and a reflection of the sun on the concrete) have a strong glare with 6 light streaks going outwards. There is also a lens flare effect with chromatic aberration, and the bloom uses a lens dirt texture to create large circular patterns of higher brightness (like dust on a lens).
December 23, 2025 at 1:21 PM
hexaquo.at
More work on procedural lens flares in #Godot.

If you want to have a look at the (still very messy!) code: github.com/kb173/godot-...

Outline of how it works:
1. Clip bright spots from the rendered image
2. Warp these spots to create ghosts and a halo
3. Blur
4. Overlay based on a dirt texture
December 18, 2025 at 9:55 PM
Reposted by Karl
sebaaltonen.bsky.social
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
hexaquo.at
Finally learning CompositorEffects #Godot

Lens flare based on this blog: john-chapman-graphics.blogspot.com/2013/02/pseu...
December 16, 2025 at 5:49 PM
Reposted by Karl
jendrikillner.bsky.social
Graphics Programming weekly - Issue 419 - December 7th, 2025 www.jendrikillner.com/post/graphic...
December 8, 2025 at 3:31 PM
Reposted by Karl
wildpeaks.fr
Good idea using gaussians for tiled floor vegetation:
yunfan.zone/gswt_webpage/ #3dgs #gamedev #rendering
December 3, 2025 at 8:28 PM
hexaquo.at
I often talk about bent normals for billboards, and I keep having to mention the "if (!FRONT_FACING) NORMAL = -NORMAL" workaround for correct backface lighting. I realized I could fix that myself, so I opened a PR for an intuitive material option and render_mode:
github.com/godotengine/...
#Godot
Left: a plane and a sphere with billboards scattered on it. A text below says "Default", and some billboards are noticeably darker than the others. Right: the same plane and sphere with billboards, but with smooth lighting without the dark billboards. The text below says "Keep Backface Normals". Schematic drawing. Left, titled "Original normals, matching geometry": a plane with an arrow pointing orthogonally outwards to the right, saying "original normal", and an arrow pointing into the opposite direction, saying "default behavior: flipped normal". Right, titled "Custom normals, do not match geometry": a plane with an arrow pointing straight up, parallel to the plane, saying "original normal", and the same arrow again, saying "intended backface normal". Another arrow points straight down, saying "default behavior: flipped normal".
November 26, 2025 at 4:19 PM
Reposted by Karl
andrewwillmott.bsky.social
I don't understand how they could get

(?:(?:\"|'|\]|\}|\\|\d|(?:nan|infinity|true|false|null|undefined|symbol|math)|\`|\-|\+)+[)]*;?((?:\s|-|~|!|{}|\|\||\+)*.*(?:.*=.*)))

so wrong
November 18, 2025 at 9:16 PM
hexaquo.at
On my way home from #GodotFest. Thanks so much to everyone for this incredible event! Hope to see you all again soon :)

My presentation on foliage rendering in #Godot is already up on YouTube: www.youtube.com/watch?v=U2nB...

And I also shared my slides here: slides.com/hexaquo/plan...
Karl Bittner: Plants, Polygons and Pixels: Large-Scale Vegetation Rendering in Godot #GodotFest2025
YouTube video by GodotFest
www.youtube.com
November 13, 2025 at 1:42 PM
Reposted by Karl
rystorm.com
I’m now seeing a talk about large scale vegetation rendering in Godot, by Karl Bittner.

He mentions there is an open source alternative to speedtree, which he has barely heard mentioned: EZ tree: www.eztree.dev

It even has an in-browser 3D viewer in which you can try different seeds for the trees!
Karl presenting at GodotFest
November 11, 2025 at 2:39 PM
hexaquo.at
on my way to #GodotFest! hope to meet some of you there :)
Laptop on a desk in a train next to a window. A presentation is being edited on the laptop. Outside the window are houses and hills lit by sunset. View out of the train window. A church can be seen on a nearby hill, which is otherwise covered by forest.
November 10, 2025 at 3:41 PM
Reposted by Karl
fabrizioespindola.bsky.social
The easiest way to create action lines in a shader is to take some noise and convert its UVs to polar coordinates 🙂

#godot #indiedev #gamedev
November 8, 2025 at 7:38 AM
hexaquo.at
🔜 #GodotFest

Want to see these slides (and many more) live? Then join my presentation on November 11th at GodotFest in Munich :)

#godot #gamedev
Presentation slide with the text "Plants, Polygons and Pixels: Large-Scale Vegetation Rendering in Godot". The background is a slightly blurred view over a rendered landscape. Presentation slide with the text "Geometry versus Billboards". "Geometry" is bold. On the right, a highly detailed 3D model of a tree is shown, first rendered, then shaded in white to show the intricate geometry. Presentation slide with the text "bend your normals!" and two rendered trees. The tree on the right has a clearer canopy shape due to smoother lighting. An arrow points from the left to the right tree. Presentation slide with the text "Ground-Covering Billboard Clouds" and an image of a rendered landscape. In the right half of the rendering, the plant billboards are rendered as white quads in order to show the geometry.
October 21, 2025 at 3:07 PM
Reposted by Karl
jendrikillner.bsky.social
Graphics Programming weekly - Issue 413 - October 19th, 2025 www.jendrikillner.com/post/graphic...
October 20, 2025 at 1:13 PM
Reposted by Karl
fronkongames.bsky.social
Sharp Bilinear Filters: big clean pixels for Pixel Art

#gamedev #gamedevelopment #indiedev #pixelart #gameart
Sharp Bilinear Filters: Big Clean Pixels for Pixel Art
Now that I’ve walked through the history of OpenGL and seen what I can do at what points in history, I can attack one of the long-standing problems I had with my old pixmap library. It’…
bumbershootsoft.wordpress.com
October 16, 2025 at 11:33 AM
Reposted by Karl
passivestar.bsky.social
Here's how to scatter objects in Blender 5.0 with just a few nodes ✨
Instance scattering in blender
Blender 5.0 is coming to save us from the spaghetti hell! Here’s a ridiculously simple blender 5.0 node setup that scatters objects on the surface of a mesh inside of the volume of some other mesh: An...
passivestar.xyz
October 14, 2025 at 11:45 PM
Reposted by Karl
dfeldman.org
Can you actually tell the difference between lossless and lossy compressed audio? (With your current headphones/speakers and ears)
abx.digitalfeed.net/list.html
ABX High Fidelity Test list
A set of browser-based ABX tests comparing lossless and lossy music samples
abx.digitalfeed.net
October 14, 2025 at 4:46 AM
Reposted by Karl
kelvinvanhoorn.com
Trying out 2 different approaches to leaf rendering on trees.

The first is a custom mesh, where each quad of the mesh is extended along the normals.

The second is are multimeshes of quads, where the normal is based on the vertex position relative to the center of the multimesh.

#GodotEngine
October 9, 2025 at 12:48 PM