public void addTimeRotation(float time, Quaternion rotation) {
        if (!(time >= 0f && time <= duration)) {
            throw new IllegalArgumentException("animation time out of range");
        }
        float norm = rotation.norm();
        if (norm == 0f) {
            throw new IllegalArgumentException("rotation cannot have norm=0");
        }

        float normalizingFactor = 1f / FastMath.sqrt(norm);
        Quaternion normalized = rotation.mult(normalizingFactor);
        rotations.put(time, normalized);
    }
Add a keyframe for the specified rotation at the specified time.

@param time the animation time when full rotation should be achieved
(&ge;0, &le;duration)
@param rotation the local rotation to apply to the target (not null,
non-zero norm, unaffected)
jme3-core/src/main/java/com/jme3/anim/AnimFactory.java