##MainCamera: Target Display: Display 1 Target eye: Both
##OverviewCamera: Target Display: Display 1 Target eye: None (Main Display)
- http://www.shaderslab.com/index.php?post/Echolocation-effect
- https://support.unity3d.com/hc/en-us/articles/206485253-How-do-I-get-Unity-to-playback-a-Microphone-input-in-real-time-
- http://forum.unity3d.com/threads/blow-detection-using-ios-microphone.118215/#post-801969
- http://answers.unity3d.com/questions/157940/getoutputdata-and-getspectrumdata-they-represent-t.html
- https://docs.unity3d.com/Manual/SL-DepthTextures.html