Realtime display of surfaces and lighting has been a very expensive and relatively recent thing in 3D.

But with GPU assist in Iray, realtime display is achievable and 'sort of affordable' to the hobbyist.

...here is one of Mec4d's videos:

This is a very impressive video, but you need to understand what is going on.  First of all, Cathy (Mec4d) has an impressive PC with two over-clocked Titan X  video cards. That is probably $2200 worth of video cards alone. This scene has only one 3D object in it, that is the SUV model. The street and buildings are an HDRI light and background