Is the document of Quaternion.operator* wrong?

Questions & Answers
1

Hi there,

It seems that the document of Quaternion.operator*(Quaternion lhs, Quaternion rhs) is wrong.

The document says "Rotating by the product lhs * rhs is the same as applying the two rotations in sequence, lhs first and then rhs. "

But by my experiment it seems that is opposite, the rhs is applied first, then the lhs;

e.g.:

var q1 = Quaternion.Euler(90, 0, 0);
var q2 = Quaternion.Euler(0, 90, 0);
var q3 = Quaternion.Euler(90, 90, 0);

q1*q2 == q3; //false
q2*q1 == q3; //true
2

Actually, you’re misunderstanding the order of Euler angle rotations.

Quaternion.Euler: Returns a rotation that rotates z degrees around the z axis, x degrees around the x axis, and y degrees around the y axis (in that order).

So really, when you’re using Quaternion.Euler(90, 90, 0) what it is actually equivalent to is:

Quaternion.Euler(0, 90, 0) * Quaternion.Euler(90, 0, 0)