wio

wio is a platform abstraction library, providing:

• window management and events
• clipboard access
• alert dialogs
• joystick input
• audio
• OpenGL and Vulkan WSI

Getting started

The public API can be browsed in src/wio.zig. The example directory contains a test program covering most features.

The features build option can be used to disable some functions, or enable Vulkan support.

Platform support

Tier 1

• Windows
• macOS (10.13+)
• Linux
• WebAssembly

Tier 2

Not actively tested, but most code is shared with tier 1 targets.

• OpenBSD
• NetBSD
• FreeBSD
• DragonFlyBSD
• illumos

Tier 3

Not actively tested.

• Haiku

Platform notes

Windows

wio embeds an application manifest by default. To use a custom manifest, set the win32_manifest build option to false.

If audio is enabled, wio initializes COM with options COINIT_MULTITHREADED and COINIT_DISABLE_OLE1DDE.

macOS

The example directory contains an application bundle, which can be adapted by changing the CFBundleExecutable and CFBundleName values in Info.plist.

Unix

Unix-like systems support different backends in the same executable. By default all backends are enabled, the unix_backends build option can be used to limit the choices.

When building a project that uses wio, passing -fsys=wio to zig build will link libraries explicitly (rather than using dlopen).

It is recommended to expose unix_backends in your build script and document the existance of -fsys=wio, to assist with packaging your project.

The following libraries are loaded for the X11 backend:

• libX11.so.6
• libXcursor.so.1
• libGL.so.1 (if OpenGL is enabled)

The following libraries are loaded for the Wayland backend:

• libwayland-client.so.0
• libxkbcommon.so.0
• libdecor-0.so.0
• libwayland-egl.so.1 (if OpenGL is enabled)
• libEGL.so.1 (if OpenGL is enabled)

The following libraries are loaded under Linux:

• libudev.so.1 (if joysticks are enabled)
• libpulse.so.0 (if audio is enabled)

WebAssembly

If OpenGL is enabled, wio imports createContext and makeContextCurrent from the gl module. The example directory contains bindings to WebGL 1.

glGetProcAddress always returns null.

Platform-specific API

The following variables and fields may be considered part of the public API for a given platform:

Windows

• Window.backend.window is the Win32 HWND
• wio.backend.win32 is a set of Win32 API bindings

macOS

• Window.backend.window is the AppKit NSWindow

Unix

wio.backend.active is an enum variable specifying the backend in use:

.x11

• wio.backend.x11.display is the Xlib display
• Window.backend.x11.window is the Xlib window

.wayland

• wio.backend.wayland.display is the Wayland wl_display
• Window.backend.wayland.surface is the Wayland wl_surface

WebAssembly

• Window.backend.id is the index into the JavaScript window array