There are 3 kinds of emptiness. Sad one, when you miss something. Better one, when fear of frustration is gone. The best one, when time is distorted, everything but a single thing ceases to exist and you get superpowers. Visualization in Pixar's Soul - Into The Zone.
You get into the flow when balancing on the edge of your skill while doing things you believe in. A fresh mind and comfortable environment help too — I always felt like a burlak in classroom or office.
I rely on my unconscious mind a lot for solving difficult problems or when I need creativity. It means I typically work in bursts through the day or night, including weekends. You can call it Ping Pong method or effective usage of shower thoughts and incubation.
So I needed some "filler" when the unconsciousness works. I also wanted to learn guitar. I can't sing, can't keep the rhythm and can't produce loud noises at night. Hence learning to play simpler fingerstyle songs started.
I was learning pieces like Romanza Un Dia de Noviembre Dust in the Wind The Heart Asks Pleasure First Watermark (Enya) Moonlight Sonata (if my left hand was fresh before gym) main themes from Metro 2033 and Requiem for a Dream. It was on cheap guitar with small and slow fingers, but I felt the similar magic like writing code.
However, I'm creator so the urge to "compose" own song was stronger than motivation to improve my guitar skills. Those days, I was listening Philip Glass and similar, even electronic music with a lot of repetitions and patterns to keep me focused and relaxed. It was natural to draw some inspiration from them. I've written The Emptiness tablature with pencil while testing on guitar and then (years later) I've recreated it in the app Steinberg Dorico.