sphere.cpp findExtremePoints crash if points vector is emtpy

Crash at sphere.cpp, line 113 if points vector is empty.

This happens if I pass the parent entity to the entity constructor when creating a new object in an already visible scene. Then the entity is added to the scene immediately and the bounding volume calculation is done before the vertices are set.

auto *entity = new SomeEntity(parentEntity);
entity->setDataForEntity();

The problem can be avoided by setting the parent explicitly after the data is set, like this

auto *entity = new SomeEntity;
entity->setDataForEntity();
entity->setParent(parentEntity);