feat: shared egl context across outputs

crates/adapters/src/rendering/egl/context.rs

@@ -107,6 +107,14 @@ impl EGLContext {
         EGLContextBuilder::new()
     }
 
+    #[must_use]
+    pub(super) fn from_raw(
+        surface: Surface<WindowSurface>,
+        context: PossiblyCurrentContext,
+    ) -> Self {
+        Self { surface, context }
+    }
+
     fn ensure_current(&self) -> Result<()> {
         if !self.context.is_current() {
             self.context

crates/adapters/src/rendering/egl/context_factory.rs

@@ -0,0 +1,237 @@
+use super::context::EGLContext;
+use crate::errors::{EGLError, LayerShikaError, Result};
+use glutin::{
+    api::egl::{
+        config::Config,
+        context::{NotCurrentContext, PossiblyCurrentContext},
+        display::Display,
+        surface::Surface,
+    },
+    config::ConfigTemplateBuilder,
+    context::ContextAttributesBuilder,
+    prelude::*,
+    surface::{SurfaceAttributesBuilder, WindowSurface},
+};
+use log::{debug, info};
+use raw_window_handle::{
+    RawDisplayHandle, RawWindowHandle, WaylandDisplayHandle, WaylandWindowHandle,
+};
+use slint::PhysicalSize;
+use std::{cell::RefCell, ffi::c_void, num::NonZeroU32, ptr::NonNull, rc::Rc};
+use wayland_client::backend::ObjectId;
+
+pub struct RenderContextFactory {
+    shared_state: RefCell<Option<SharedRenderState>>,
+}
+
+struct SharedRenderState {
+    display: Display,
+    config: Config,
+    primary_context: PossiblyCurrentContext,
+}
+
+impl RenderContextFactory {
+    #[must_use]
+    pub fn new() -> Rc<Self> {
+        Rc::new(Self {
+            shared_state: RefCell::new(None),
+        })
+    }
+
+    pub fn create_context(
+        &self,
+        display_id: &ObjectId,
+        surface_id: &ObjectId,
+        size: PhysicalSize,
+    ) -> Result<EGLContext> {
+        let mut state = self.shared_state.borrow_mut();
+
+        if state.is_none() {
+            info!("Creating primary EGL context (will be shared with subsequent contexts)");
+            let new_state = self.create_primary_context(display_id, surface_id, size)?;
+            *state = Some(new_state);
+        }
+
+        let Some(shared_state) = state.as_ref() else {
+            return Err(LayerShikaError::InvalidInput {
+                message: "Shared state initialization failed".into(),
+            });
+        };
+
+        if shared_state.primary_context.is_current() {
+            debug!("Creating shared context while primary is current");
+            self.create_shared_context_from_current(
+                &shared_state.display,
+                &shared_state.config,
+                &shared_state.primary_context,
+                surface_id,
+                size,
+            )
+        } else {
+            debug!("Creating shared context (primary not current)");
+            self.create_shared_context(
+                &shared_state.display,
+                &shared_state.config,
+                &shared_state.primary_context,
+                surface_id,
+                size,
+            )
+        }
+    }
+
+    #[allow(clippy::unused_self)]
+    fn create_primary_context(
+        &self,
+        display_id: &ObjectId,
+        surface_id: &ObjectId,
+        size: PhysicalSize,
+    ) -> Result<SharedRenderState> {
+        let display_handle = create_wayland_display_handle(display_id)?;
+        let display = unsafe { Display::new(display_handle) }
+            .map_err(|e| EGLError::DisplayCreation { source: e.into() })?;
+
+        let config_template = ConfigTemplateBuilder::default();
+        let config = select_config(&display, config_template)?;
+
+        let context_attributes = ContextAttributesBuilder::default();
+        let not_current = create_context(&display, &config, context_attributes)?;
+
+        let surface_handle = create_surface_handle(surface_id)?;
+        let surface = create_surface(&display, &config, surface_handle, size)?;
+
+        let primary_context = not_current
+            .make_current(&surface)
+            .map_err(|e| EGLError::MakeCurrent { source: e.into() })?;
+
+        info!("Primary EGL context created successfully");
+
+        Ok(SharedRenderState {
+            display,
+            config,
+            primary_context,
+        })
+    }
+
+    #[allow(clippy::unused_self)]
+    fn create_shared_context(
+        &self,
+        display: &Display,
+        config: &Config,
+        share_context: &PossiblyCurrentContext,
+        surface_id: &ObjectId,
+        size: PhysicalSize,
+    ) -> Result<EGLContext> {
+        let context_attributes = ContextAttributesBuilder::default().with_sharing(share_context);
+
+        let not_current =
+            unsafe { display.create_context(config, &context_attributes.build(None)) }
+                .map_err(|e| EGLError::ContextCreation { source: e.into() })?;
+
+        let surface_handle = create_surface_handle(surface_id)?;
+        let surface = create_surface(display, config, surface_handle, size)?;
+
+        let context = not_current
+            .make_current(&surface)
+            .map_err(|e| EGLError::MakeCurrent { source: e.into() })?;
+
+        info!("Shared EGL context created successfully");
+
+        Ok(EGLContext::from_raw(surface, context))
+    }
+
+    #[allow(clippy::unused_self)]
+    fn create_shared_context_from_current(
+        &self,
+        display: &Display,
+        config: &Config,
+        share_context: &PossiblyCurrentContext,
+        surface_id: &ObjectId,
+        size: PhysicalSize,
+    ) -> Result<EGLContext> {
+        let context_attributes = ContextAttributesBuilder::default().with_sharing(share_context);
+
+        let not_current =
+            unsafe { display.create_context(config, &context_attributes.build(None)) }
+                .map_err(|e| EGLError::ContextCreation { source: e.into() })?;
+
+        let surface_handle = create_surface_handle(surface_id)?;
+        let surface = create_surface(display, config, surface_handle, size)?;
+
+        let context = not_current
+            .make_current(&surface)
+            .map_err(|e| EGLError::MakeCurrent { source: e.into() })?;
+
+        info!("Shared EGL context created successfully (from current)");
+
+        Ok(EGLContext::from_raw(surface, context))
+    }
+}
+
+impl Default for RenderContextFactory {
+    fn default() -> Self {
+        Self {
+            shared_state: RefCell::new(None),
+        }
+    }
+}
+
+fn create_wayland_display_handle(display_id: &ObjectId) -> Result<RawDisplayHandle> {
+    let display = NonNull::new(display_id.as_ptr().cast::<c_void>()).ok_or_else(|| {
+        LayerShikaError::InvalidInput {
+            message: "Failed to create NonNull pointer for display".into(),
+        }
+    })?;
+    let handle = WaylandDisplayHandle::new(display);
+    Ok(RawDisplayHandle::Wayland(handle))
+}
+
+fn select_config(
+    glutin_display: &Display,
+    config_template: ConfigTemplateBuilder,
+) -> Result<Config> {
+    let mut configs = unsafe { glutin_display.find_configs(config_template.build()) }
+        .map_err(|e| EGLError::ConfigSelection { source: e.into() })?;
+    configs
+        .next()
+        .ok_or_else(|| EGLError::NoCompatibleConfig.into())
+}
+
+fn create_context(
+    glutin_display: &Display,
+    config: &Config,
+    context_attributes: ContextAttributesBuilder,
+) -> Result<NotCurrentContext> {
+    unsafe { glutin_display.create_context(config, &context_attributes.build(None)) }
+        .map_err(|e| EGLError::ContextCreation { source: e.into() }.into())
+}
+
+fn create_surface_handle(surface_id: &ObjectId) -> Result<RawWindowHandle> {
+    let surface = NonNull::new(surface_id.as_ptr().cast::<c_void>()).ok_or_else(|| {
+        LayerShikaError::InvalidInput {
+            message: "Failed to create NonNull pointer for surface".into(),
+        }
+    })?;
+    let handle = WaylandWindowHandle::new(surface);
+    Ok(RawWindowHandle::Wayland(handle))
+}
+
+fn create_surface(
+    glutin_display: &Display,
+    config: &Config,
+    surface_handle: RawWindowHandle,
+    size: PhysicalSize,
+) -> Result<Surface<WindowSurface>> {
+    let width = NonZeroU32::new(size.width).ok_or_else(|| LayerShikaError::InvalidInput {
+        message: "Width cannot be zero".into(),
+    })?;
+
+    let height = NonZeroU32::new(size.height).ok_or_else(|| LayerShikaError::InvalidInput {
+        message: "Height cannot be zero".into(),
+    })?;
+
+    let attrs =
+        SurfaceAttributesBuilder::<WindowSurface>::new().build(surface_handle, width, height);
+
+    unsafe { glutin_display.create_window_surface(config, &attrs) }
+        .map_err(|e| EGLError::SurfaceCreation { source: e.into() }.into())
+}

crates/adapters/src/rendering/egl/mod.rs

@@ -1 +1,2 @@
 pub mod context;
+pub mod context_factory;

crates/adapters/src/wayland/shell_adapter.rs

@@ -15,7 +15,7 @@ use smithay_client_toolkit::reexports::protocols_wlr::layer_shell::v1::client::z
 use crate::{
     errors::{EventLoopError, LayerShikaError, RenderingError, Result},
     rendering::{
-        egl::context::EGLContext,
+        egl::context_factory::RenderContextFactory,
         femtovg::{main_window::FemtoVGWindow, renderable_window::RenderableWindow},
         slint_integration::platform::CustomSlintPlatform,
     },
@@ -55,6 +55,8 @@ pub struct WaylandWindowingSystem {
     connection: Rc<Connection>,
     event_queue: EventQueue<AppState>,
     event_loop: EventLoop<'static, AppState>,
+    #[allow(dead_code)]
+    render_factory: Rc<RenderContextFactory>,
 }
 
 impl WaylandWindowingSystem {
@@ -64,13 +66,15 @@ impl WaylandWindowingSystem {
         let event_loop =
             EventLoop::try_new().map_err(|e| EventLoopError::Creation { source: e })?;
 
-        let state = Self::init_state(config, &connection, &mut event_queue)?;
+        let render_factory = RenderContextFactory::new();
+        let state = Self::init_state(config, &connection, &mut event_queue, &render_factory)?;
 
         Ok(Self {
             state,
             connection,
             event_queue,
             event_loop,
+            render_factory,
         })
     }
 
@@ -97,6 +101,7 @@ impl WaylandWindowingSystem {
         event_queue: &mut EventQueue<AppState>,
         pointer: &Rc<WlPointer>,
         layer_surface_config: &LayerSurfaceConfig,
+        render_factory: &Rc<RenderContextFactory>,
     ) -> Result<Vec<OutputSetup>> {
         let mut setups = Vec::new();
 
@@ -128,7 +133,7 @@ impl WaylandWindowingSystem {
             let main_surface_id = surface_ctx.surface.id();
 
             let window =
-                Self::initialize_renderer(&surface_ctx.surface, &connection.display(), config)?;
+                Self::initialize_renderer(&surface_ctx.surface, &connection.display(), config, render_factory)?;
 
             let mut builder = WindowStateBuilder::new()
                 .with_component_definition(config.component_definition.clone())
@@ -217,6 +222,7 @@ impl WaylandWindowingSystem {
         config: &WaylandWindowConfig,
         connection: &Connection,
         event_queue: &mut EventQueue<AppState>,
+        render_factory: &Rc<RenderContextFactory>,
     ) -> Result<AppState> {
         let global_ctx = GlobalContext::initialize(connection, &event_queue.handle())?;
         let layer_surface_config = Self::create_layer_surface_config(config);
@@ -237,6 +243,7 @@ impl WaylandWindowingSystem {
             global_ctx.viewporter.clone(),
             connection.display(),
             Rc::new(connection.clone()),
+            Rc::clone(render_factory),
         );
 
         let setups = Self::create_output_setups(
@@ -246,6 +253,7 @@ impl WaylandWindowingSystem {
             event_queue,
             &pointer,
             &layer_surface_config,
+            render_factory,
         )?;
 
         let platform = Self::setup_platform(&setups)?;
@@ -321,14 +329,15 @@ impl WaylandWindowingSystem {
         surface: &Rc<WlSurface>,
         display: &WlDisplay,
         config: &WaylandWindowConfig,
+        render_factory: &Rc<RenderContextFactory>,
     ) -> Result<Rc<FemtoVGWindow>> {
         let init_size = PhysicalSize::new(1, 1);
 
-        let context = EGLContext::builder()
-            .with_display_id(display.id())
-            .with_surface_id(surface.id())
-            .with_size(init_size)
-            .build()?;
+        let context = render_factory.create_context(
+            &display.id(),
+            &surface.id(),
+            init_size,
+        )?;
 
         let renderer = FemtoVGRenderer::new(context)
             .map_err(|e| LayerShikaError::FemtoVGRendererCreation { source: e })?;

crates/adapters/src/wayland/surfaces/popup_manager.rs

@@ -1,5 +1,5 @@
 use crate::errors::{LayerShikaError, Result};
-use crate::rendering::egl::context::EGLContext;
+use crate::rendering::egl::context_factory::RenderContextFactory;
 use crate::rendering::femtovg::{popup_window::PopupWindow, renderable_window::RenderableWindow};
 use crate::wayland::surfaces::display_metrics::{DisplayMetrics, SharedDisplayMetrics};
 use layer_shika_domain::dimensions::LogicalSize as DomainLogicalSize;
@@ -74,10 +74,12 @@ pub struct PopupContext {
     fractional_scale_manager: Option<WpFractionalScaleManagerV1>,
     viewporter: Option<WpViewporter>,
     display: WlDisplay,
+    render_factory: Rc<RenderContextFactory>,
 }
 
 impl PopupContext {
     #[must_use]
+    #[allow(clippy::too_many_arguments)]
     pub fn new(
         compositor: WlCompositor,
         xdg_wm_base: Option<XdgWmBase>,
@@ -86,6 +88,7 @@ impl PopupContext {
         viewporter: Option<WpViewporter>,
         display: WlDisplay,
         _connection: Rc<Connection>,
+        render_factory: Rc<RenderContextFactory>,
     ) -> Self {
         Self {
             compositor,
@@ -94,6 +97,7 @@ impl PopupContext {
             fractional_scale_manager,
             viewporter,
             display,
+            render_factory,
         }
     }
 }
@@ -328,11 +332,11 @@ impl PopupManager {
             popup_surface.surface.commit();
         }
 
-        let context = EGLContext::builder()
-            .with_display_id(self.context.display.id())
-            .with_surface_id(popup_surface.surface.id())
-            .with_size(popup_size)
-            .build()?;
+        let context = self.context.render_factory.create_context(
+            &self.context.display.id(),
+            &popup_surface.surface.id(),
+            popup_size,
+        )?;
 
         let renderer = FemtoVGRenderer::new(context)
             .map_err(|e| LayerShikaError::FemtoVGRendererCreation { source: e })?;