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Quaternion transform method only works with normalized quaternions

See original GitHub issue

The Quaternion method transform requires the quaternion to be normalized, but this is not documented.

There is a better method here, which works with unnormalized quaternions, but also avoids the sqrt (see the Java code):

https://www.euclideanspace.com/maths/geometry/rotations/conversions/quaternionToMatrix/index.htm

Issue Analytics

State:
Created 4 years ago
Reactions:1
Comments:6 (4 by maintainers)

Top GitHub Comments

1reaction

httpdigestcommented, Jan 7, 2020

A new 1.9.21-SNAPSHOT build is up on oss.sonatype.org with a Quaternion.transformUnit() (which works like the old Quaternion.transform()) and a modified Quaternion.transform() which works with non-unit quaternions as well.

0reactions

httpdigestcommented, Jan 7, 2020

The only problem with adding a properties field is that it would increase the storage size required

Unlikely. Object sizes are padded for 8-byte alignment anyways. Currently, on a JDK-14, a Quaternionf instance takes 32 bytes and a padding of 4 bytes (according to JOL). Adding an additional byte makes no difference to the size.

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