static not_null<std::unique_ptr<Trajectory const>> BuildTrajectory() {
not_null<std::unique_ptr<Trajectory>> result =
make_not_null_unique<Trajectory>();
// Build a biggish protobuf for serialization.
for (int i = 0; i < 100; ++i) {
Trajectory::InstantaneousDegreesOfFreedom* idof = result->add_timeline();
Point* instant = idof->mutable_instant();
Quantity* scalar = instant->mutable_scalar();
scalar->set_dimensions(3);
scalar->set_magnitude(3 * i);
Pair* dof = idof->mutable_degrees_of_freedom();
Pair::Element* t1 = dof->mutable_t1();
Point* point1 = t1->mutable_point();
Quantity* scalar1 = point1->mutable_scalar();
scalar1->set_dimensions(1);
scalar1->set_magnitude(i);
Pair::Element* t2 = dof->mutable_t2();
Point* point2 = t2->mutable_point();
Quantity* scalar2 = point2->mutable_scalar();
scalar2->set_dimensions(2);
scalar2->set_magnitude(2 * i);
}
return std::move(result);
}
