Function eulerToQuaternion

scripts/verify-anim-t0.mjs:243–253

(x, y, z)

console.log(`=== SAMPLING ANIMATION AT t=0 ===\n`);

function eulerToQuaternion(x, y, z) {
    const cx = Math.cos(x / 2), sx = Math.sin(x / 2);
    const cy = Math.cos(y / 2), sy = Math.sin(y / 2);
    const cz = Math.cos(z / 2), sz = Math.sin(z / 2);
    return [
        sx * cy * cz - cx * sy * sz,
        cx * sy * cz + sx * cy * sz,
        cx * cy * sz - sx * sy * cz,
        cx * cy * cz + sx * sy * sz
    ];
}

function multiplyQuaternion(a, b) {
    const [ax, ay, az, aw] = a;