How does Google StreetView recognize 3D planes?

Inside Google Street View, mov开发者_C百科ing the mouse around over different buildings and stuff, it highlights the 3D plane in which that surface of the building is located.

How does it recognize this thing? Is it done automatically by machine algorithms, or manually in the preprocessing?

Read this to get your answer. What Google does is it gets a panoramic view by stitching multiple images together, and then the device measures the relative distance of every object around it (through lasers), and constructs a 3D model of the surroundings based on that.

You want to look into space-filling-curves. A sfc reduce the 3d complexity to a 1d complexity. A sfc subdivide the 3d space into 8 tiles thus it resemble an octree.