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externals/oboe/samples/MegaDrone/README.md

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+Mega Drone
+==========
+Ever wondered what 100 square waves sound like when played together? Well now you can find out! 
+
+Mega Drone is an app which creates 100 oscillators, combines their output in a mixer and plays the resulting sound.
+
+This sample demonstrates how to obtain the lowest latency and optimal computational throughput by:
+
+1) Leaving Oboe to choose the best default stream properties for the current device
+2) Setting performance mode to LowLatency
+3) Setting sharing mode to Exclusive
+4) Setting the buffer size to 2 bursts
+5) Using the `-Ofast` compiler optimization flag, even when building the `Debug` variant
+6) Using [`getExclusiveCores`](https://developer.android.com/reference/android/os/Process#getExclusiveCores()) (API 24+) and thread affinity to bind the audio thread to the best available CPU core(s)
+
+This code was presented at [AES Milan](http://www.aes.org/events/144/) and [Droidcon Berlin](https://www.de.droidcon.com/) as part of a talk on Oboe.
+
+The [following article explaining how to debug CPU performance problems](https://medium.com/@donturner/debugging-audio-glitches-on-android-ed10782f9c64) may also be useful when looking at this code.
+
+Implementation details
+---
+The stream properties are left to Oboe as such the app must output audio data in a format which matches that of the stream. 
+
+Four different formats are supported: 
+
+|Channel count|Format|
+|-------------|------|
+|1 - Mono|16-bit int|
+|2 - Stereo|16-bit int|
+|1 - Mono|Float|
+|2 - Stereo|Float|
+
+The signal chain for mono streams is: 
+
+    Oscillators->Mixer
+
+For stereo chains a mono to stereo converter is added to the end of the chain: 
+
+    Oscillators->Mixer->MonoToStereo
+ 
+The compiler optimization flag `-Ofast` can be found in [CMakeLists.txt](CMakeLists.txt). 
+ 
+Screenshots
+-----------
+![megadrone-screenshot](megadrone-screenshot.png)