Ingot

A huge thank you to rfandango

Ingot exists because of rfandango and his emulator, hakuX, which plays original Xbox games on Android phones. He did the hard part: recreating the Xbox's processor, its system software and its graphics chip well enough that games run fast and look right. Without hakuX I would never have attempted any of this. Everything Ingot does stands on top of his work.

And a big thank you to the xemu team too. hakuX grew out of xemu, the original Xbox emulator for Windows, macOS and Linux, and Ingot's sound still comes from xemu's recreation of the Xbox's audio chip. Years of their research into how the Xbox works are in here.

Why it has a different name

I thought this was going to be as easy as forking hakuX (making my own copy of its code) and slapping a Metal backend on it. Unfortunately, I wasn't so lucky. Getting games to run well on a Mac meant changing a lot more than that:

• A new way to draw. Every game's graphics have to be redrawn by your computer's graphics chip. On Android, hakuX does that with Vulkan, a graphics system Macs don't have. Macs use Apple's own, called Metal. So the whole graphics side had to be rewritten for Metal, including translating the Xbox's little graphics programs (shaders) into Metal's language. Along the way came fixes for problems Android never had, like flickering ground in sports games and slowdowns from loading textures.
• Memory comes in different-sized pages. Computers hand out memory in fixed-size blocks called pages, a bit like a notebook where you can only lock or unlock a whole sheet at a time. The Xbox uses small 4 KB pages; Apple silicon Macs use pages four times bigger, 16 KB. When the emulator needs to watch or protect one Xbox page, the Mac can only lock the whole big page, which drags three of its neighbours along with it. Making that work, and fast, meant rebuilding how the emulator lays out and guards the game's memory.
• A different kind of processor. A processor only understands instructions written for its architecture, its "native language." The Xbox has an Intel Pentium III, which speaks x86, the same family as most Windows PCs. Apple silicon Macs, like most phones and tablets, are built on ARM, which speaks a completely different language. So a game's code can't just run on a Mac: it has to be translated from x86 into ARM while you play. hakuX does that with a translator called FEX, and because Android phones are ARM too, that part was already a great fit. But FEX was made for Linux, and it had to be taught to run on macOS, where a few things behave differently. One of those differences made games crash after about half an hour of play until it was tracked down.
• A real Mac app around it. The Android app was replaced with a Mac game library, a Mac game window, support for Xbox, PlayStation and other Mac controllers, and Mac sound output.

With that much changed, it isn't fair to call it hakuX, or to send its bugs his way. hakuX's author doesn't support Ingot, so please report Ingot problems on Ingot's GitHub, not to hakuX. And if you enjoy Ingot, go give hakuX and xemu a star.