multiply method
Multiply entries in this with entries in arg.
Implementation
void multiply(Vector3 arg) {
final Float64List argStorage = arg._v3storage;
_v3storage[0] = _v3storage[0] * argStorage[0];
_v3storage[1] = _v3storage[1] * argStorage[1];
_v3storage[2] = _v3storage[2] * argStorage[2];
}