Hackers' Pub

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`(` condition `)`	Combines the operators within the parentheses first.	`(#HackersPub OR "Hackers' Pub" OR "Hackers Pub") lang:en`

GDC Presentation Reviews @GDCPresoReviews@mastodon.gamedev.place

3/11/2026, 9:47:10 PM

Public

GDC 2016: “Math for Game Programmers: Rotational Joint Limits in Quaternion Space” by Gino van den Bergen of Dtecta https://gdcvault.com/play/1023558/Math-for-Game-Programmers-Rotational

This presentation had a lot of background, whereas the actual technique was presented pretty quickly.

The technique is:

1. Reduce the 4-dimensional space of quaternions to 3D by just dropping the real component (you can always get it back because there are only 3 degrees of freedom in a rotation quaternion)

1/n

Math for Game Programmers: Rotational Joint Limits in Quaternion Space

Enforcing rotational limits on a shoulder or hip joints has historically often been achieved by converting from quaternions to

gdcvault.com

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