Setup with Zig and Raylib

Using Zig and Raylib together is nothing new.
However, what they often don't do us support web, which was the main purpose of this.
This is a proof of concept, the code that makes it work is pretty hacky at times.
Namely, Emscripten can't find the entry point so I had to make one in C and link that into the project,
and the Zig application itself is compiled for wasi when the final output is emscripten.

Zig is supposedly going to properly support web builds using emscripten in the future, as suggested here

How to build

The project builds and runs like any other zig project

zig build run

However, if you want a web build, things get a bit more complicated

zig build run -Dtarget=wasm32-emscripten --sysroot [path to emsdk]/upstream/emscripten

the --sysroot is required since emscripten itself is required separately from Zig's webassembly compiler.

Once the project has finished building, it can be found in 'zig-out/bin/applicationhtml/'

How it works

When the project is built, it first builds Raylib into a static library.
Then it links that with itself. Pretty standard stuff.

When building for the web though, things get pretty weird.
Instead of building the project as an executable it creates a static library.
Then it first builds a special C file that simply boots the Zig code
since emscripten can't find any entry points within Zig code.
Then, using Emscripten again, it links all three pieces (the C entry point, the Zig code, and Raylib)
and outputs the entire thing as an HTML page.