Added Wayland support

Author: john01dav

Cargo.toml

@@ -11,6 +11,8 @@ thiserror = "1.0.30"
 raw-window-handle = "0.4.2"
 
 [target.'cfg(target_os = "linux")'.dependencies]
+tempfile = "3.3.0"
+wayland-client = {version = "0.29", features = ["use_system_lib"], default_features = false}
 x11-dl = "2.19.1"
 
 [target.'cfg(target_os = "windows")'.dependencies]

README.md

@@ -42,7 +42,7 @@ For now, the priority for new platforms is:
  - AppKit ✅ (Thanks to [Seo Sanghyeon](https://github.com/sanxiyn)!)
  - Orbital ❌
  - UiKit ❌
- - Wayland ❌
+ - Wayland ✅ (Wayland support in winit is immature at the moment, so it might be wise to force X11 if you're using winit)
  - Web ❌
  - Win32 ✅
  - WinRt ❌

src/error.rs

@@ -15,3 +15,10 @@ pub enum SoftBufferError<W: HasRawWindowHandle> {
     #[error("Platform error")]
     PlatformError(Option<String>, Option<Box<dyn Error>>)
 }
+
+pub(crate) fn unwrap<T, E: std::error::Error + 'static, W: HasRawWindowHandle>(res: Result<T, E>, str: &str) -> Result<T, SoftBufferError<W>>{
+    match res{
+        Ok(t) => Ok(t),
+        Err(e) => Err(SoftBufferError::PlatformError(Some(str.into()), Some(Box::new(e))))
+    }
+}

src/lib.rs

@@ -10,8 +10,11 @@ mod win32;
 mod cg;
 #[cfg(target_os = "linux")]
 mod x11;
+#[cfg(target_os = "linux")]
+mod wayland;
 
 mod error;
+
 pub use error::SoftBufferError;
 
 use raw_window_handle::{HasRawWindowHandle, RawWindowHandle};
@@ -33,9 +36,11 @@ impl<W: HasRawWindowHandle> GraphicsContext<W> {
     ///  - Ensure that the passed object is valid to draw a 2D buffer to
     pub unsafe fn new(window: W) -> Result<Self, SoftBufferError<W>> {
         let raw_handle = window.raw_window_handle();
-        let imple = match raw_handle {
+        let imple: Box<dyn GraphicsContextImpl> = match raw_handle {
             #[cfg(target_os = "linux")]
             RawWindowHandle::Xlib(xlib_handle) => Box::new(x11::X11Impl::new(xlib_handle)?),
+            #[cfg(target_os = "linux")]
+            RawWindowHandle::Wayland(wayland_handle) => Box::new(wayland::WaylandImpl::new(wayland_handle)?),
             #[cfg(target_os = "windows")]
             RawWindowHandle::Win32(win32_handle) => Box::new(win32::Win32Impl::new(&win32_handle)?),
             #[cfg(target_os = "macos")]

src/wayland.rs

@@ -0,0 +1,69 @@
+use raw_window_handle::{HasRawWindowHandle, WaylandHandle};
+use tempfile::tempfile;
+use wayland_client::{Display, sys::client::wl_display, GlobalManager, protocol::{wl_shm::WlShm, wl_buffer::WlBuffer, wl_surface::WlSurface}, Main, Proxy, EventQueue};
+use crate::{GraphicsContextImpl, SoftBufferError, error::unwrap};
+use std::{fs::File, os::unix::prelude::{AsRawFd, FileExt}, io::Write};
+
+pub struct WaylandImpl {
+    _event_queue: EventQueue,
+    surface: WlSurface,
+    shm: Main<WlShm>,
+    tempfile: File,
+    buffer: Option<WaylandBuffer>
+}
+
+struct WaylandBuffer{
+    width: i32,
+    height: i32,
+    buffer: Main<WlBuffer>
+}
+
+impl WaylandImpl {
+
+    pub unsafe fn new<W: HasRawWindowHandle>(handle: WaylandHandle) -> Result<Self, SoftBufferError<W>> {
+        let display = Display::from_external_display(handle.display as *mut wl_display);
+        let mut event_queue = display.create_event_queue();
+        let attached_display = (*display).clone().attach(event_queue.token());
+        let globals = GlobalManager::new(&attached_display);
+        unwrap(event_queue.sync_roundtrip(&mut (), |_, _, _| unreachable!()), "Failed to make round trip to server")?;
+        let shm = unwrap(globals.instantiate_exact::<WlShm>(1), "Failed to instantiate Wayland Shm")?;
+        let tempfile = unwrap(tempfile(), "Failed to create temporary file to store buffer.")?;
+        let surface = Proxy::from_c_ptr(handle.surface as _).into();
+        Ok(Self{
+            _event_queue: event_queue,
+            surface, shm, tempfile,
+            buffer: None
+        })
+    }
+
+    fn ensure_buffer_size(&mut self, width: i32, height: i32){
+        if !self.check_buffer_size_equals(width, height){
+            let pool = self.shm.create_pool(self.tempfile.as_raw_fd(), width*height*4);
+            let buffer = pool.create_buffer(0, width, height, width*4, wayland_client::protocol::wl_shm::Format::Xrgb8888);
+            self.buffer = Some(WaylandBuffer{
+                width,
+                height,
+                buffer
+            });
+        }
+    }
+
+    fn check_buffer_size_equals(&self, width: i32, height: i32) -> bool{
+        match &self.buffer{
+            Some(buffer) => buffer.width == width && buffer.height == height,
+            None => false
+        }
+    }
+
+}
+
+impl GraphicsContextImpl for WaylandImpl {
+    unsafe fn set_buffer(&mut self, buffer: &[u32], width: u16, height: u16) {
+        self.ensure_buffer_size(width as i32, height as i32);
+        let wayland_buffer = self.buffer.as_mut().unwrap();
+        self.tempfile.write_at(std::slice::from_raw_parts(buffer.as_ptr() as *const u8, buffer.len()*4), 0).expect("Failed to write buffer to temporary file.");
+        self.tempfile.flush().expect("Failed to flush buffer to temporary file.");
+        self.surface.attach(Some(&wayland_buffer.buffer), 0, 0);
+        self.surface.commit();
+    }
+}