Placing Images in 3d Space
A computer uses UV's to figure out where to apply a bitmap or image in a 3D model. This isn't the only way to control a shader in a 3D environment but is widely used method in VFX, games and many other industries. VRED has recently implemented UV editors into it's user interface. Most 3D software's have the ability to UV unwrap their 3D models. I do my UV editing and Environmental modeling outside of VRED. Since VRED can read FBX files that carry UV data, than any software with those capabilities can be used.
This gives us the ability to "paint" on any amount of lights and shadows. As long as where we apply this is static, then we can get a very realistic effect with minimum cost to our GPU. Giving us the ability to experience extremely high end lighting and shadows in real time. This is a method that is widely used in Architecture visualization. We are taking advantage of the fact that static lighting doesn't change.
The cost
Every Texture you add to a scene will need to be stored in a GPU's VRAM, this means we can't just add 4k textures to every corner of our scene. With proper texturing you can have a very good result with very little cost to your GPU. A full 3D studio scenes when done correctly will cost the GPU less than 1 gb of VRAM. If you are running P6000, they have the capacity for 24 gb. So in the end we are only using a small fraction of our resources.
Putting it all Together
Now that our 3D environment is looking very nice we can use some of the same logic to make our reflections look realistic and immersive.