Computes the point along a ray at the given time.
time can be positive, negative, or zero.Example
czm_ray ray = czm_ray(vec3(0.0), vec3(1.0, 0.0, 0.0)); // origin, direction vec3 v = czm_pointAlongRay(ray, 2.0); // (2.0, 0.0, 0.0)