I've been looking for an engine to use, but most of them (Unity, Unreal, Paradox3d, etc.) revolve around editors and object placement. As a programmer, and a single-person team, I'm not exactly focused on asset-rich setpieces like a more traditional game, but something focused more on dynamically-generated content. Obviously, this is possible in the aforementioned engines, but the paradigm kind of gets in the way, and I've found myself having trouble learning how to navigate them.

Basically, I'm looking for something more like a library than a full-on application; basically a really beefy and fuller-featured SDL. I'm not too particular on language, but mostly keen on C# or a somewhat modern C++ codebase, and targeting the PC platform primarily w/ DX11 or OGL4. Does anyone know any good free or no-up-front-cost engines that fit that description?

Would like something like XNA/MonoGame fit the bill? They aren't engines per-say, but rather frameworks that handle a lot of the nuts 'n bolts when it comes to graphics, sound, etc.

I think Ogre3D might work for you.

This:

http://gameplay3d.org/

Thanks for the responses, everyone!

I'm generally targeting a DX11 feature level (I like to tinker too much to be limited to DX9), so some of these are non-starters (particularly Urho3D and MonoGame). Polycode especially seems editor-driven. I'll give Magnum and gameplay3D a further look in that light, and I'll check out Ogre3D. I looked at that engine a long time ago and it wasn't particularly well-designed, but that was 8 years ago and a lot can change.