Here s a quick tutorial on how to create realtime reflections in unity 5.
Floor reflection unity.
It may be possible to get some sort of sensors in the floor and then you re doing entirely custom things to read the data.
More likely you d use a camera in the ceiling and probably want to process it with opencv.
It is commonly used to create more subtle reflections such as on wet floor surfaces or in puddles.
I suspect that this will be the hardest part of what you need to accomplish.
You can probably use this for more things like wall mirrors and multiple reflections in the same scene but that would require quite a bit more scripting magic.
More info see in glossary window that are used for editing the size and probe origin properties directly within the scene.
I can t wrap my head around how do you make a floor that reflect the environment and just the floor.
From my understanding you create a material push the smoothness to 1 and then place a reflection probe in the scene and all the materials smooth enough.
Screen space reflection is a technique for reusing screen space data to calculate reflections.
I like this opencv asset for unity.
This approach is very hacky but you can use the new reflection probes in unity 5 to easily create realtime reflections for something like a reflective floor.
With the leftmost button size selected.