Merge pull request #155 from YaLTeR/fix-dimensions

anvil: retrieve buffer dimensions on commit

anvil/src/buffer_utils.rs

@@ -0,0 +1,59 @@
+use std::{cell::RefCell, rc::Rc};
+
+use slog::Logger;
+
+#[cfg(feature = "egl")]
+use smithay::backend::egl::{BufferAccessError, EGLDisplay};
+use smithay::{
+    reexports::wayland_server::protocol::wl_buffer::WlBuffer,
+    wayland::shm::with_buffer_contents as shm_buffer_contents,
+};
+
+/// Utilities for working with `WlBuffer`s.
+#[derive(Clone)]
+pub struct BufferUtils {
+    #[cfg(feature = "egl")]
+    egl_display: Rc<RefCell<Option<EGLDisplay>>>,
+    log: Logger,
+}
+
+impl BufferUtils {
+    /// Creates a new `BufferUtils`.
+    #[cfg(feature = "egl")]
+    pub fn new(egl_display: Rc<RefCell<Option<EGLDisplay>>>, log: Logger) -> Self {
+        Self { egl_display, log }
+    }
+
+    /// Creates a new `BufferUtils`.
+    #[cfg(not(feature = "egl"))]
+    pub fn new(log: Logger) -> Self {
+        Self { log }
+    }
+
+    /// Returns the dimensions of an image stored in the buffer.
+    #[cfg(feature = "egl")]
+    pub fn dimensions(&self, buffer: &WlBuffer) -> Option<(i32, i32)> {
+        // Try to retrieve the EGL dimensions of this buffer, and, if that fails, the shm dimensions.
+        self.egl_display
+            .borrow()
+            .as_ref()
+            .and_then(|display| display.egl_buffer_dimensions(buffer))
+            .or_else(|| self.shm_buffer_dimensions(buffer))
+    }
+
+    /// Returns the dimensions of an image stored in the buffer.
+    #[cfg(not(feature = "egl"))]
+    pub fn dimensions(&self, buffer: &WlBuffer) -> Option<(i32, i32)> {
+        self.shm_buffer_dimensions(buffer)
+    }
+
+    /// Returns the dimensions of an image stored in the shm buffer.
+    fn shm_buffer_dimensions(&self, buffer: &WlBuffer) -> Option<(i32, i32)> {
+        shm_buffer_contents(buffer, |_, data| (data.width, data.height))
+            .map_err(|err| {
+                warn!(self.log, "Unable to load buffer contents"; "err" => format!("{:?}", err));
+                err
+            })
+            .ok()
+    }
+}

anvil/src/main.rs

@@ -12,6 +12,7 @@ use smithay::reexports::{calloop::EventLoop, wayland_server::Display};
 
 #[macro_use]
 mod shaders;
+mod buffer_utils;
 mod glium_drawer;
 mod input_handler;
 mod shell;

anvil/src/shell.rs

@@ -29,7 +29,10 @@ use smithay::{
     },
 };
 
-use crate::window_map::{Kind as SurfaceKind, WindowMap};
+use crate::{
+    buffer_utils::BufferUtils,
+    window_map::{Kind as SurfaceKind, WindowMap},
+};
 
 define_roles!(Roles =>
     [ XdgSurface, XdgSurfaceRole ]
@@ -98,6 +101,7 @@ impl PointerGrab for MoveSurfaceGrab {
 
 pub fn init_shell(
     display: &mut Display,
+    buffer_utils: BufferUtils,
     log: ::slog::Logger,
 ) -> (
     CompositorToken<Roles>,
@@ -109,7 +113,7 @@ pub fn init_shell(
     let (compositor_token, _, _) = compositor_init(
         display,
         move |request, surface, ctoken| match request {
-            SurfaceEvent::Commit => surface_commit(&surface, ctoken),
+            SurfaceEvent::Commit => surface_commit(&surface, ctoken, &buffer_utils),
             SurfaceEvent::Frame { callback } => callback
                 .implement_closure(|_, _| unreachable!(), None::<fn(_)>, ())
                 .done(0),
@@ -273,10 +277,15 @@ pub fn init_shell(
 pub struct SurfaceData {
     pub buffer: Option<wl_buffer::WlBuffer>,
     pub texture: Option<crate::glium_drawer::TextureMetadata>,
+    pub dimensions: Option<(i32, i32)>,
     pub input_region: Option<RegionAttributes>,
 }
 
-fn surface_commit(surface: &wl_surface::WlSurface, token: CompositorToken<Roles>) {
+fn surface_commit(
+    surface: &wl_surface::WlSurface,
+    token: CompositorToken<Roles>,
+    buffer_utils: &BufferUtils,
+) {
     token.with_surface_data(surface, |attributes| {
         attributes.user_data.insert_if_missing(SurfaceData::default);
         let data = attributes.user_data.get_mut::<SurfaceData>().unwrap();
@@ -292,6 +301,8 @@ fn surface_commit(surface: &wl_surface::WlSurface, token: CompositorToken<Roles>
                     old_buffer.release();
                 }
                 data.texture = None;
+                // If this fails, the buffer will be discarded later by the drawing code.
+                data.dimensions = buffer_utils.dimensions(data.buffer.as_ref().unwrap());
             }
             Some(None) => {
                 // erase the contents
@@ -299,6 +310,7 @@ fn surface_commit(surface: &wl_surface::WlSurface, token: CompositorToken<Roles>
                     old_buffer.release();
                 }
                 data.texture = None;
+                data.dimensions = None;
             }
             None => {}
         }
@@ -306,12 +318,10 @@ fn surface_commit(surface: &wl_surface::WlSurface, token: CompositorToken<Roles>
 }
 
 fn get_size(attrs: &SurfaceAttributes) -> Option<(i32, i32)> {
-    attrs.user_data.get::<SurfaceData>().and_then(|data| {
-        data.texture
-            .as_ref()
-            .map(|ref meta| meta.dimensions)
-            .map(|(x, y)| (x as i32, y as i32))
-    })
+    attrs
+        .user_data
+        .get::<SurfaceData>()
+        .and_then(|data| data.dimensions)
 }
 
 fn contains_point(attrs: &SurfaceAttributes, point: (f64, f64)) -> bool {

anvil/src/udev.rs

@@ -61,6 +61,7 @@ use smithay::{
     },
 };
 
+use crate::buffer_utils::BufferUtils;
 use crate::glium_drawer::GliumDrawer;
 use crate::input_handler::AnvilInputHandler;
 use crate::shell::{init_shell, MyWindowMap, Roles};
@@ -85,6 +86,11 @@ pub fn run_udev(mut display: Display, mut event_loop: EventLoop<()>, log: Logger
     #[cfg(feature = "egl")]
     let active_egl_context = Rc::new(RefCell::new(None));
 
+    #[cfg(feature = "egl")]
+    let buffer_utils = BufferUtils::new(active_egl_context.clone(), log.clone());
+    #[cfg(not(feature = "egl"))]
+    let buffer_utils = BufferUtils::new(log.clone());
+
     let display = Rc::new(RefCell::new(display));
 
     /*
@@ -92,7 +98,8 @@ pub fn run_udev(mut display: Display, mut event_loop: EventLoop<()>, log: Logger
      */
     init_shm_global(&mut display.borrow_mut(), vec![], log.clone());
 
-    let (compositor_token, _, _, window_map) = init_shell(&mut display.borrow_mut(), log.clone());
+    let (compositor_token, _, _, window_map) =
+        init_shell(&mut display.borrow_mut(), buffer_utils, log.clone());
 
     /*
      * Initialize session

anvil/src/winit.rs

@@ -23,6 +23,7 @@ use smithay::{
 
 use slog::Logger;
 
+use crate::buffer_utils::BufferUtils;
 use crate::glium_drawer::GliumDrawer;
 use crate::input_handler::AnvilInputHandler;
 use crate::shell::init_shell;
@@ -42,10 +43,15 @@ pub fn run_winit(display: &mut Display, event_loop: &mut EventLoop<()>, log: Log
 
     let (w, h) = renderer.get_framebuffer_dimensions();
     #[cfg(feature = "egl")]
-    let drawer = GliumDrawer::init(renderer, egl_display, log.clone());
+    let drawer = GliumDrawer::init(renderer, egl_display.clone(), log.clone());
     #[cfg(not(feature = "egl"))]
     let drawer = GliumDrawer::init(renderer, log.clone());
 
+    #[cfg(feature = "egl")]
+    let buffer_utils = BufferUtils::new(egl_display, log.clone());
+    #[cfg(not(feature = "egl"))]
+    let buffer_utils = BufferUtils::new(log.clone());
+
     let name = display.add_socket_auto().unwrap().into_string().unwrap();
     info!(log, "Listening on wayland socket"; "name" => name.clone());
     ::std::env::set_var("WAYLAND_DISPLAY", name);
@@ -58,7 +64,7 @@ pub fn run_winit(display: &mut Display, event_loop: &mut EventLoop<()>, log: Log
 
     init_shm_global(display, vec![], log.clone());
 
-    let (compositor_token, _, _, window_map) = init_shell(display, log.clone());
+    let (compositor_token, _, _, window_map) = init_shell(display, buffer_utils, log.clone());
 
     let dnd_icon = Arc::new(Mutex::new(None));
 

src/backend/egl/mod.rs

@@ -472,6 +472,42 @@ impl EGLDisplay {
             Err(BufferAccessError::ContextLost)
         }
     }
+
+    /// Try to receive the dimensions of a given [`WlBuffer`].
+    ///
+    /// In case the buffer is not managed by EGL (but e.g. the [`wayland::shm` module](::wayland::shm)) or the
+    /// context has been lost, `None` is returned.
+    pub fn egl_buffer_dimensions(&self, buffer: &WlBuffer) -> Option<(i32, i32)> {
+        if let Some(display) = self.egl.upgrade() {
+            let mut width: i32 = 0;
+            if unsafe {
+                ffi::egl::QueryWaylandBufferWL(
+                    *display,
+                    buffer.as_ref().c_ptr() as *mut _,
+                    ffi::egl::WIDTH as i32,
+                    &mut width as *mut _,
+                ) == 0
+            } {
+                return None;
+            }
+
+            let mut height: i32 = 0;
+            if unsafe {
+                ffi::egl::QueryWaylandBufferWL(
+                    *display,
+                    buffer.as_ref().c_ptr() as *mut _,
+                    ffi::egl::HEIGHT as i32,
+                    &mut height as *mut _,
+                ) == 0
+            } {
+                return None;
+            }
+
+            Some((width, height))
+        } else {
+            None
+        }
+    }
 }
 
 #[cfg(feature = "native_lib")]