Daniel Holden
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theorangeduck.bsky.social
Daniel Holden
@theorangeduck.bsky.social
Animation & Machine Learning at Epic Games. Ex Ubisoft La Forge. Programmer & Occasional Writer. https://theorangeduck.com/
Time for another short story :)

theorangeduck.com/page/review-...
October 26, 2025 at 2:06 PM
This year I had the chance to visit the Peace Museum in Hiroshima. Of all the things I saw in Japan this is the place that will stay with me forever.

theorangeduck.com/page/hiroshima
Hiroshima
Computer Science, Machine Learning, Programming, Art, Mathematics, Philosophy, and Short Fiction
theorangeduck.com
October 7, 2025 at 12:16 PM
With a bit of help from the authors I've added another huge high quality dataset to my Geno retargetings. This time the very nice InterAct dataset (hku-cg.github.io/interact/).

You can find it here: github.com/orangeduck/i...
September 17, 2025 at 12:04 AM
My latest article is on the problem of joint-error propagation - and some techniques for tackling it when doing Machine Learning or other data-driven numerical methods.

theorangeduck.com/page/joint-e...
August 24, 2025 at 1:31 PM
I've just pushed up a version of my GenoView project but implemented in Python (using raylib bindings). Hopefully that is useful to anyone doing ML research building interactive animation systems who wants to make use of PyTorch, Numpy, etc.

github.com/orangeduck/GenoViewPython
GitHub - orangeduck/GenoViewPython: An example raylib python application for viewing animation on the Geno character
An example raylib python application for viewing animation on the Geno character - GitHub - orangeduck/GenoViewPython: An example raylib python application for viewing animation on the Geno character
github.com
August 19, 2025 at 12:15 PM
We have a rare opening on our team for an Animation Programmer. If working with us on shipping Machine Learning animation tech inside UE appeals to you, please go ahead and apply!

www.epicgames.com/site/en-US/c...
Join Epic Games Today! See Our Latest Career and Job Opportunities.
Visit Epic Games Careers to see the latest jobs and employment opportunities. Join an exciting team pushing the limits in gaming and interactive entertainment.
www.epicgames.com
June 27, 2025 at 5:27 PM
I've added an appendix to my page on debug drawing text with lines with a contribution from @mikkomononen.bsky.social and his version of a non-monospaced font based on the Hershey Fonts Simplex characters:

theorangeduck.com/page/debug-d...
June 18, 2025 at 2:44 PM
There may not be many obvious alternatives, but CLIP is not a great embedding for describing motion. It's trained on static images so has a confused concept of time/tense/ordering, will often focus on the object rather than the action, and usually interprets verbs as nouns:
June 14, 2025 at 10:07 PM
More than once I've wanted to debug draw text in a game scene but found it not as easy as expected. I made a lookup table that allows you to draw text via line segments. It was a fun little weekend project, even if I'm sure it's something people have done before!

theorangeduck.com/page/debug-d...
April 8, 2025 at 8:45 PM
Time for another long blog post... and today it's all about how we handle the temporal aspect of animation data. And more specifically, how to approach things from a signal processing perspective, covering up-sampling, down-sampling, and everything in-between.

theorangeduck.com/page/filteri...
April 4, 2025 at 3:22 PM
Jérôme Eippers' YouTube channel is quickly becoming a goldmine for Animation Programming. He is covering so many classic animation papers - reviving a lot of great ideas and techniques that are either under-utilized or forgotten by the industry.

www.youtube.com/@JeromeEippe...
Animation Tech
In this channel we will be looking at the technical side of animation and physic in the video game industry. Let's dig into whitepapers and reimplement them in python to learn from them. I'm Jerome ...
www.youtube.com
March 1, 2025 at 6:11 PM
Learned a new spring fact from my colleague @rat-face.bsky.social recently. For a critically damped spring tracking a target moving at a constant velocity, the amount of time the spring will lag behind the target is given by "halflife / ln(2)". Added to my blog post theorangeduck.com/page/spring-...
Spring-It-On: The Game Developer's Spring-Roll-Call
Computer Science, Machine Learning, Programming, Art, Mathematics, Philosophy, and Short Fiction
theorangeduck.com
February 25, 2025 at 1:28 AM
I've uploaded a retargeted version of the 100STYLE dataset matching the other datasets: github.com/orangeduck/1...

I wasn't sure if I should add it at first. The quality is lower due to the inertial capture, and it's missing finger motion, but overall I figured it's still worth it.
January 24, 2025 at 6:52 PM
It's been a while since I did a pure Machine Learning article on my blog, but today I have a post for you about adding noise to Neural Networks, and some fun experiments with Flow-Matching:

theorangeduck.com/page/noise-n...
December 29, 2024 at 3:23 PM
My latest article is about one of my favorite techniques in graphics - Müller's method of Polar Decomposition.

It also details some variations, including one which is ~2x faster to compute with more regular convergence.

theorangeduck.com/page/variati...
November 23, 2024 at 4:27 PM