Compared to Unity, Unreal Engine 4 is much more user friendly and has a blueprint system which will not require you code.

This is ready to make the next AAA game.

The engine, including full access to source code, is free to use; a 5% royalty is due only when you monetize your game or other interactive off-the-shelf product and your gross revenues from that product exceed $1,000,000 USD.

Voxel cone tracing is a similar algorithm to ray tracing, but uses thick rays instead of pixel thin rays to be able vastly decrease the amount of computational power needed.

Unreal Engine 4 has photo-realistic rendering and has a visual scripting system called Blueprints.