The programmer of legendary emulator ZSNES just resurfaced after 24 years to give his first-ever interview and spill the secrets of its magical netplay, snowy UI and unbelievable speed on 1997 PCs

A major contributor from the early days of emulation finally gets his flowers.

In 1997, two young hobbyists released two pieces of software that more or less prompted a new wave of interest in "retro" games—which were, at that point, really just a few years old. The first punch was Nesticle, a Nintendo Entertainment System emulator that quite suddenly made it free and easy to play Nintendo's '80s and early '90s games on a PC. The second punch, delivered near the end of the year, was ZSNES, which did the same for much newer Super Nintendo games. And it was fast—even on the modest PCs of the era.

"When I was 16 years old I started learning assembly, and I got so fascinated with optimization, making everything as fast as possible," said zsKnight, the developer behind ZSNES, in an interview last week. While most software is written in higher level programming languages like C++ that are easier to work with, even at a young age zsKnight was skilled enough in low level assembly language to start using it to program his own emulator.

Back in 1997, computer processors weren't yet fast enough to accurately emulate game consoles. While the Super Nintendo's 3.58MHz CPU was much slower and simpler than, say, a 133 MHz Intel Pentium CPU, every operation the console performs every fraction of a second has to be interpreted and then rewritten for the PC's processor, which isn't nearly as efficient. zsKnight recalled trying an early SNES emulator called Super Pasofami, which ran at about 10 fps on his PC and didn't even support sound.

He wondered if he could do better.

"I started coding everything in pure assembly—until the Windows port there was not a single line of C code in there," he said. "It's optimized to the brim. When I first started it, I wanted a Super Nintendo emulator that could play at full speed on my computer, but I actually did not expect to meet that goal."

As far as I'm aware this is the first time zsKnight has done an interview about his time working on ZS

Source: PC Gamer (https://www.pcgamer.com)