function longslerp(a, b, t ) {	
	const u = [ a.nx*a.nL, a.ny*a.nL, a.nz*a.nL]
	const v = [ b.nx*b.nL, b.ny*b.nL, b.nz* b.nL]
	const p = axisAngleToQuaternion(u);
	const q = axisAngleToQuaternion(v);
	const r = slerp(p, q, t);
	return quatArrayToLogQuat( r );		
}
// convert lnQuat_Start, lnQuat_Dest, 0-1 return lnQuat of inbetween rotation
convert lnQuat_Start, lnQuat_Dest, 0-1 return lnQuat of inbetween rotation
convert lnQuat_Start lnQuat_Dest 0 - 1 return lnQuat of inbetween rotation
function longslerp(a, b, t ) {	
	const u = [ a.nx*a.nL, a.ny*a.nL, a.nz*a.nL]
	const v = [ b.nx*b.nL, b.ny*b.nL, b.nz* b.nL]
	const p = axisAngleToQuaternion(u);
	const q = axisAngleToQuaternion(v);
	const r = slerp(p, q, t);
	return quatArrayToLogQuat( r );		
}
function longslerp ( a , b , t ) { const u = [ a . nx * a . nL , a . ny * a . nL , a . nz * a . nL ] const v = [ b . nx * b . nL , b . ny * b . nL , b . nz * b . nL ] const p = axisAngleToQuaternion ( u ) ; const q = axisAngleToQuaternion ( v ) ; const r = slerp ( p , q , t ) ; return quatArrayToLogQuat ( r ) ; }
convert lnQuat_Start, lnQuat_Dest, 0-1 return lnQuat of inbetween rotation
convert lnQuat_Start lnQuat_Dest 0 - 1 return lnQuat of inbetween rotation