So, I remember watching The Dark Knight and thinking how the sonar mapping from the movie seemed a bit of a stretch. To refresh your memory:

Here we are just 6 years later, and in a slightly different capacity. Google is working with many people and companies from all over the world to make  the sonar mapping become real! Though I can imagine this is going to make security more difficult and complex.

Also, I want to mention that I’m very happy to see Johnny Chung Lee being a part of this project! I love his videos from several years ago utilizing a Wii to do similar 3D mapping!