All a game engine is is a collection of tools and libs that allow you to make games. Most developers don't buy an off the shelf ready to use game engine. They create the tools and libs and then when they have their engine up and running, start creating the game. This is often a long and drawn out process that develops over time, much of the functionality isn't there at the start, and only comes together in the last 6-8 months as things adapt to suit a particular game. Some require more modability than others.
Only reason torque is easy to pick up is that it was built with MP and mods in mind. It definately is an Engine, but a lot of the nuts and bolts limit what you can do, and much of it would have to be rebuilt from the ground up to suit more varied games than FPS.
Only reason torque is easy to pick up is that it was built with MP and mods in mind. It definately is an Engine, but a lot of the nuts and bolts limit what you can do, and much of it would have to be rebuilt from the ground up to suit more varied games than FPS.