Standalone spherical interpolation for quaternions, from gl-matrix.
var slerp =var out =// out is now [0, 0.707106, 0, 0.707106]
slerp(out, a, b, t)
Interpolates from quaternion
b with the given
t alpha, storing the result in
out. Returns the
b are all 4-component arrays in the form
[x, y, z, w].
MIT, see LICENSE.md for details.