Zig OpenGL

This will be a series of articles about my journey on learning a bit
of OpenGL using zig, instead of C/C++.
A bit of context.

While i was searching the best online resources for learning opengl, i
found https://learnopengl.com/, which seems to be the most complete
and definetely the best for beginners.

Meanwhile, a friend of mine point me out about a online workshop by
Loris Cro on Zig.

So i thought, why shouldn't i combine those two and try to learn opengl using zig.
In this article i'll show you how to setup the dev environment specifically for zig.

Premises

This series of articles doesn't have the presumption to teach you
something. I'm myself learning both zig and OpenGL. However i may take
something for granted.

Requirements

Zig (0.13)
GLFW
OpenGL binding generator (es. Glad)

Basically for working with OpenGL, you need something that handles the
context, windows and user inputs.
From https://learnopengl.com/Getting-started/Creating-a-window

GLFW is a library, written in C, specifically targeted at
OpenGL. GLFW gives us the bare necessities required for rendering
goodies to the screen. It allows us to create an OpenGL context,
define window parameters, and handle user input, which is plenty
enough for our purposes.

Here we have two path that we can follow.
The first one is using the native zig bindings from Mach
https://github.com/slimsag/mach-glfw

This is the path that i didn't follow because i want to experiment
myself one of the most acclaimed features of Zig, the C/C++ interoperability.

The second one, which i follow, is using
https://github.com/slimsag/glfw This basically is a porting of the C
library using zig as build system (instead of cmake or whatever).

GLFW

First thing first we need to fetch the dependency, which is as easy as

zig fetch --save git+https://github.com/slimsag/glfw

This will generate a build.zig.zon which list the dependencies fetched.

.dependencies = .{
    .glfw = .{
        .url = "git+https://github.com/slimsag/glfw.git#e6f377baed70a7bef9fa08d808f40b64c5136bf6",
        .hash = "1220c15e66c13f9633fcfd50b5ed265f74f2950c98b1f1defd66298fa027765e0190",
    },
},

From there we can leverage the build.zig written by slimsag and
link GLFW within our zig program.

const glfw = b.dependency("glfw", .{ .target = target, .optimize = optimize });
exe.linkLibrary(glfw.artifact("glfw"));

(don't worry, i'll link the entire repo at the end of the article.)

Finally this allow us to import in our src/main.zig GLFW

const glfw = @import("glfw");

OpenGL bindings

Before starting my journey with OpenGL i thought that opengl was a
simple library, but it's not! OpenGL's API defines signatures and
name of functions, but they need to be find at runtime, and this is
totally OS/GPU dependant.