Here is some very frequent code to get a theremin like instrument working with a Rasberry Pi and a Lidar sensor.
Expend at your have chance, this venture will not be any longer maintained, however shared in hope it’ll be helpful.

Expend sudo startScript.sh to start it up, you would possibly possibly well possibly possibly moreover manually trigger this or quandary it as a start script

You’d like an OLED and a Lidar sensor to get this working, once I in fact get time I would possibly possibly well moreover merely upload a schematic..

OLED:

https://www.raspberrypi-gawk.co.uk/2018/04/i2c-oled-tell-module-with-raspberry-pi/

Lidar :
https://makersportal.com/blog/distance-detection-with-the-tf-luna-lidar-and-raspberry-pi

PS: To get this to work you ether ought to present your Pi precise into a USB midi instrument or expend my other venture to transmit Midi over bluetooth.

https://github.com/Mylab6/PiBluetoothMidSetup