Dimensions like GTA

Who knows how to create dimensions for interiors like in GTA Online and GTA SAMP?

Dimensions for interiors? Do you mean faking interior’s through the likes of windows? Have a look at Unreal 4 Materials 11 Windows with fake interiors (Bump Offset) - YouTube for this effect. Dave runs a great tutorial on Parallax shaders

I meant that the players are in the same interior but do not see each other.