> Ogre is not a game engine. Unreal, Unity, CryEngine, Frosbite are game engines.
Including the editor tools and asset pipeline into the term "game engine" has only really become fashionable after Unity became so incredible popular, from that moment on, Unity and 'game engine' became synomymous and everybody else (including Unreal) copied the Unity workflow model. Most of the team works in the integrated editor tool in Unity most of the time, thus the editor tool has become synonymous with "engine" but it is actually the "factory line". But this integrated game development model isn't the only possible model just because it has become so popular.
It's just as well possible to create a mainly "programmer driven" game engine where tools are only used to provide the asset data, but the actual game is fully built in code (IMHO it would be much less confusing if the term 'engine' would only be used for the runtime parts that actually 'drive' the game).
Including the editor tools and asset pipeline into the term "game engine" has only really become fashionable after Unity became so incredible popular, from that moment on, Unity and 'game engine' became synomymous and everybody else (including Unreal) copied the Unity workflow model. Most of the team works in the integrated editor tool in Unity most of the time, thus the editor tool has become synonymous with "engine" but it is actually the "factory line". But this integrated game development model isn't the only possible model just because it has become so popular.
It's just as well possible to create a mainly "programmer driven" game engine where tools are only used to provide the asset data, but the actual game is fully built in code (IMHO it would be much less confusing if the term 'engine' would only be used for the runtime parts that actually 'drive' the game).