JSFiddle - React, Tailwind, and code Playground

HTML

<script src="//cdnjs.cloudflare.com/ajax/libs/gl-matrix/2.1.0/gl-matrix-min.js"></script>

JavaScript

console.clear();

var q = quat.create();
quat.rotateZ(q, q, Math.PI);
console.log(q);

var v = vec3.fromValues(5, 0, 0);
vec3.transformQuat(v, v, q);
console.log(v);

/*
[0, 0, 1, 6.123234262925839e-17]

[-5, 6.123233998228043e-16, 0]
*/




var q2 = quat.create();
quat.rotateZ(q2, q2, Math.PI);
console.log(q2);

var v2 = vec3.fromValues(5, 5, 0);
vec3.transformQuat(v2, v2, q2);
console.log(v2);

/*
[0, 0, 1, 6.123234262925839e-17]

[-5, -5, 0]
*/