# mach/glfw - Ziggified GLFW bindings [](https://github.com/hexops/mach-glfw/actions) 
Ziggified GLFW bindings that [Mach engine](https://github.com/hexops/mach) uses, with 100% API coverage, zero-fuss installation, cross compilation, and more.
This repository is a separate copy of the same library in the [main Mach repository](https://github.com/hexops/mach), and is automatically kept in sync, so that anyone can use this library in their own project / engine if they like!
## Zero fuss installation, cross compilation, and more
[Just as with Mach](https://github.com/hexops/mach#zero-fuss-installation--cross-compilation), you get zero fuss installation & cross compilation using these GLFW bindings. **only `zig` and `git` are needed to build from any OS and produce binaries for every OS.** No system dependencies at all.
## 100% API coverage, 130+ tests, etc.
These bindings have 100% API coverage of GLFW v3.3.4. Every function, type, constant, etc. has been wrapped in a ziggified API.
There are 130+ tests, and CI tests on all major platforms as well as cross-compilation between platforms:
[platform support table](https://github.com/hexops/mach#supported-platforms)
## What does a ziggified GLFW API offer?
Why create a ziggified GLFW wrapper, instead of just using `@cImport` and interfacing with GLFW directly? You get:
- Errors as [zig errors](https://ziglang.org/documentation/master/#Errors) instead of via a callback function.
- `true` and `false` instead of `c.GLFW_TRUE` and `c.GLFW_FALSE` constants.
- Generics, so you can just use `window.hint` instead of `glfwWindowHint`, `glfwWindowHintString`, etc.
- **Enums**, always know what value a GLFW function can accept as everything is strictly typed. And use the nice Zig syntax to access enums, like `window.getKey(.escape)` instead of `c.glfwGetKey(window, c.GLFW_KEY_ESCAPE)`
- Slices instead of C pointers and lengths.
- [packed structs](https://ziglang.org/documentation/master/#packed-struct) represent bit masks, so you can use `if (joystick.down and joystick.right)` instead of `if (joystick & c.GLFW_HAT_DOWN and joystick & c.GLFW_HAT_RIGHT)`, etc.
- Methods, e.g. `my_window.hint(...)` instead of `glfwWindowHint(my_window, ...)`
## How do I use OpenGL, Vulkan, WebGPU, etc. with this?
You'll need to bring your own library for this. Some are:
- (Vulkan) https://github.com/Snektron/vulkan-zig (also see https://github.com/Avokadoen/zig_vulkan)
- (OpenGL) https://github.com/ziglibs/zgl
## Examples
A minimal Vulkan example can be found in the [mach-glfw-vulkan-example](https://github.com/hexops/mach-glfw-vulkan-example) repository:
## Getting started
### Adding dependency (using Git)
In a `libs` subdirectory of the root of your project:
```sh
git clone https://github.com/hexops/mach-glfw
```
Then in your `build.zig` add:
```zig
...
const glfw = @import("libs/mach-glfw/build.zig");
pub fn build(b: *Builder) !void {
...
exe.addPackage(glfw.pkg);
try glfw.link(b, exe, .{});
}
```
### (optional) Adding dependency using Gyro
```sh
gyro add --src github hexops/mach-glfw --root src/main.zig --alias glfw
gyro add --build_dep --src github hexops/mach-glfw --root build.zig --alias build-glfw
```
Then in your `build.zig` add:
```zig
...
const pkgs = @import("deps.zig").pkgs;
const glfw = @import("build-glfw");
pub fn build(b: *Builder) !void {
...
exe.addPackage(pkgs.glfw);
try glfw.link(b, exe, .{});
}
```
**Note: You should use `gyro build` instead of `zig build` to use gyro**
# Next steps
Now in your code you may import and use GLFW:
```zig
const glfw = @import("glfw");
pub fn main() !void {
try glfw.init(.{});
defer glfw.terminate();
// Create our window
const window = try glfw.Window.create(640, 480, "Hello, mach-glfw!", null, null, .{});
defer window.destroy();
// Wait for the user to close the window.
while (!window.shouldClose()) {
try glfw.pollEvents();
}
}
```
## A warning about error handling
Unless the action you're performing is truly critical to your application continuing further, you should avoid using `try`.
This is because GLFW unfortunately must return errors for _a large portion_ of its functionality on some platforms, but especially for Wayland - so ideally your application is resiliant to such errors and merely e.g. logs failures that are not critical.
Instead of `try window.getPos()` for example, you may use:
```zig
const pos = window.getPos() catch |err| {
std.log.err("failed to get window position: error={}\n", .{err});
return;
};
```
Here is a rough list of functionality Wayland does not support:
- `Window.setIcon`
- `Window.setPos`, `Window.getPos`
- `Window.iconify`, `Window.focus`
- `Monitor.setGamma`
- `Monitor.getGammaRamp`, `Monitor.setGammaRamp`
## Join the community
Join the Mach engine community [on Matrix chat](https://matrix.to/#/#hexops:matrix.org) to discuss this project, ask questions, get help, etc.
## Issues
Issues are tracked in the [main Mach repository](https://github.com/hexops/mach/issues?q=is%3Aissue+is%3Aopen+label%3Aglfw).
## Contributing
Contributions are very welcome. Pull requests must be sent to [the main repository](https://github.com/hexops/mach/tree/main/glfw) to avoid some complex merge conflicts we'd get by accepting contributions in both repositories. Once the changes are merged there, they'll get sync'd to this repository automatically.
For now mach/glfw tracks the latest `master` revision of GLFW, as recorded [in this file](https://github.com/hexops/glfw/blob/main/VERSION), as this version has critical undefined behavior fixes required for GLFW to work with Zig. We will switch to stable releases of GLFW once GLFW 3.4 is tagged.