Add a render thread

The default event loop on winit, at least on Windows is too slow. See
rust-windowing/winit#2782

src/renderer/cursor_renderer/mod.rs

@@ -13,6 +13,7 @@ use crate::{
     renderer::animation_utils::*,
     renderer::{GridRenderer, RenderedWindow},
     settings::{ParseFromValue, SETTINGS},
+    window::UserEvent,
 };
 
 use blink::*;
@@ -198,7 +199,7 @@ impl CursorRenderer {
         renderer
     }
 
-    pub fn handle_event(&mut self, event: &Event<()>) {
+    pub fn handle_event(&mut self, event: &Event<UserEvent>) {
         if let Event::WindowEvent {
             event: WindowEvent::Focused(is_focused),
             ..

src/renderer/mod.rs

@@ -24,6 +24,7 @@ use crate::{
     event_aggregator::EVENT_AGGREGATOR,
     profiling::tracy_zone,
     settings::*,
+    window::UserEvent,
     WindowSettings,
 };
 
@@ -34,7 +35,7 @@ pub use rendered_window::{
     LineFragment, RenderedWindow, WindowDrawCommand, WindowDrawDetails, WindowPadding,
 };
 
-pub use opengl::{build_context, Context as WindowedContext};
+pub use opengl::{build_context, build_window, Context as WindowedContext};
 pub use vsync::*;
 
 #[derive(SettingGroup, Clone)]
@@ -134,7 +135,7 @@ impl Renderer {
         }
     }
 
-    pub fn handle_event(&mut self, event: &Event<()>) {
+    pub fn handle_event(&mut self, event: &Event<UserEvent>) {
         self.cursor_renderer.handle_event(event);
     }
 

src/renderer/opengl.rs

@@ -60,20 +60,25 @@ fn gen_config(mut config_iterator: Box<dyn Iterator<Item = Config> + '_>) -> Con
     config_iterator.next().unwrap()
 }
 
-pub fn build_context<TE>(
-    cmd_line_settings: &CmdLineSettings,
+pub fn build_window<TE>(
     winit_window_builder: WindowBuilder,
     event_loop: &EventLoop<TE>,
-) -> Context {
+) -> (Window, Config) {
     let template_builder = ConfigTemplateBuilder::new()
         .with_stencil_size(8)
         .with_transparency(true);
     let (window, config) = DisplayBuilder::new()
         .with_window_builder(Some(winit_window_builder))
         .build(event_loop, template_builder, gen_config)
         .expect("Failed to create Window");
-    let window = window.expect("Could not create Window");
+    (window.expect("Could not create Window"), config)
+}
 
+pub fn build_context(
+    window: Window,
+    config: Config,
+    cmd_line_settings: &CmdLineSettings,
+) -> Context {
     let gl_display = config.display();
     let raw_window_handle = window.raw_window_handle();
 

src/window/keyboard_manager.rs

@@ -2,7 +2,7 @@ use crate::{
     bridge::{SerialCommand, UiCommand},
     event_aggregator::EVENT_AGGREGATOR,
     settings::SETTINGS,
-    window::KeyboardSettings,
+    window::{KeyboardSettings, UserEvent},
 };
 use winit::{
     event::{ElementState, Event, Ime, KeyEvent, WindowEvent},
@@ -37,7 +37,7 @@ impl KeyboardManager {
         }
     }
 
-    pub fn handle_event(&mut self, event: &Event<()>) {
+    pub fn handle_event(&mut self, event: &Event<UserEvent>) {
         match event {
             Event::WindowEvent {
                 event: WindowEvent::Focused(_focused),