From 85bf8a195abb1a1303f1ed8f939b7da260ab8f48 Mon Sep 17 00:00:00 2001
From: Simon Hausmann <simon.hausmann@sixtyfps.io>
Date: Wed, 17 Jun 2020 14:37:47 +0200
Subject: [PATCH] Improve EventLoop encapsulation

Hide the winit loop and extract it only in the GL renderer
---
 sixtyfps_runtime/corelib/eventloop.rs         | 14 ++++++++++----
 sixtyfps_runtime/corelib/graphics.rs          |  6 +++---
 sixtyfps_runtime/corelib/lib.rs               |  4 ++--
 sixtyfps_runtime/rendering_backends/gl/lib.rs |  2 +-
 4 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/sixtyfps_runtime/corelib/eventloop.rs b/sixtyfps_runtime/corelib/eventloop.rs
index 12b88a321..e8c5f1962 100644
--- a/sixtyfps_runtime/corelib/eventloop.rs
+++ b/sixtyfps_runtime/corelib/eventloop.rs
@@ -20,11 +20,13 @@ thread_local! {
     pub(crate) static ALL_WINDOWS: RefCell<std::collections::HashMap<winit::window::WindowId, Weak<dyn GenericWindow>>> = RefCell::new(std::collections::HashMap::new());
 }
 
-pub struct EventLoop(pub(crate) winit::event_loop::EventLoop<()>);
+pub struct EventLoop {
+    winit_loop: winit::event_loop::EventLoop<()>,
+}
 
 impl EventLoop {
     pub fn new() -> Self {
-        Self(winit::event_loop::EventLoop::new())
+        Self { winit_loop: winit::event_loop::EventLoop::new() }
     }
 
     #[allow(unused_mut)] // mut need changes for wasm
@@ -82,7 +84,7 @@ impl EventLoop {
         };
 
         #[cfg(not(target_arch = "wasm32"))]
-        self.0.run_return(run_fn);
+        self.winit_loop.run_return(run_fn);
         #[cfg(target_arch = "wasm32")]
         {
             // Since wasm does not have a run_return function that takes a non-static closure,
@@ -93,8 +95,12 @@ impl EventLoop {
                 &mut ControlFlow,
             ));
             RUN_FN_TLS.set(&mut run_fn, move || {
-                self.0.run(|e, t, cf| RUN_FN_TLS.with(|mut run_fn| run_fn(e, t, cf)))
+                self.winit_loop.run(|e, t, cf| RUN_FN_TLS.with(|mut run_fn| run_fn(e, t, cf)))
             });
         }
     }
+
+    pub fn get_winit_event_loop(&self) -> &winit::event_loop::EventLoop<()> {
+        &self.winit_loop
+    }
 }
diff --git a/sixtyfps_runtime/corelib/graphics.rs b/sixtyfps_runtime/corelib/graphics.rs
index 4116dd1ef..30311d956 100644
--- a/sixtyfps_runtime/corelib/graphics.rs
+++ b/sixtyfps_runtime/corelib/graphics.rs
@@ -108,14 +108,14 @@ impl<Backend: GraphicsBackend> RenderingCache<Backend> {
 
 pub struct GraphicsWindow<Backend: GraphicsBackend + 'static> {
     graphics_backend_factory:
-        Box<dyn Fn(&winit::event_loop::EventLoop<()>, winit::window::WindowBuilder) -> Backend>,
+        Box<dyn Fn(&crate::eventloop::EventLoop, winit::window::WindowBuilder) -> Backend>,
     graphics_backend: Option<Backend>,
     rendering_cache: RenderingCache<Backend>,
 }
 
 impl<Backend: GraphicsBackend + 'static> GraphicsWindow<Backend> {
     pub fn new(
-        graphics_backend_factory: impl Fn(&winit::event_loop::EventLoop<()>, winit::window::WindowBuilder) -> Backend
+        graphics_backend_factory: impl Fn(&crate::eventloop::EventLoop, winit::window::WindowBuilder) -> Backend
             + 'static,
     ) -> Rc<RefCell<Self>> {
         let this = Rc::new(RefCell::new(Self {
@@ -222,7 +222,7 @@ impl<Backend: GraphicsBackend> crate::eventloop::GenericWindow
 
             let mut this = self.borrow_mut();
             let factory = this.graphics_backend_factory.as_mut();
-            let backend = factory(&event_loop.0, window_builder);
+            let backend = factory(&event_loop, window_builder);
 
             let window_id = backend.window().id();
 
diff --git a/sixtyfps_runtime/corelib/lib.rs b/sixtyfps_runtime/corelib/lib.rs
index 59213484d..26d33ac5e 100644
--- a/sixtyfps_runtime/corelib/lib.rs
+++ b/sixtyfps_runtime/corelib/lib.rs
@@ -45,12 +45,12 @@ pub use abi::properties::{EvaluationContext, Property};
 #[doc(inline)]
 pub use abi::signals::Signal;
 
-mod eventloop;
+pub mod eventloop;
 mod item_rendering;
 
 pub fn run_component<GraphicsBackend: graphics::GraphicsBackend + 'static>(
     component: vtable::VRef<crate::abi::datastructures::ComponentVTable>,
-    graphics_backend_factory: impl Fn(&winit::event_loop::EventLoop<()>, winit::window::WindowBuilder) -> GraphicsBackend
+    graphics_backend_factory: impl Fn(&eventloop::EventLoop, winit::window::WindowBuilder) -> GraphicsBackend
         + 'static,
 ) {
     use eventloop::GenericWindow;
diff --git a/sixtyfps_runtime/rendering_backends/gl/lib.rs b/sixtyfps_runtime/rendering_backends/gl/lib.rs
index d92b6684d..2ed726c35 100644
--- a/sixtyfps_runtime/rendering_backends/gl/lib.rs
+++ b/sixtyfps_runtime/rendering_backends/gl/lib.rs
@@ -635,6 +635,6 @@ pub extern "C" fn sixtyfps_runtime_run_component_with_gl_renderer(
     component: vtable::VRef<ComponentVTable>,
 ) {
     sixtyfps_corelib::run_component(component, |event_loop, window_builder| {
-        GLRenderer::new(&event_loop, window_builder)
+        GLRenderer::new(&event_loop.get_winit_event_loop(), window_builder)
     });
 }