manually setup redraw system

src/editor/mod.rs

@@ -72,7 +72,7 @@ impl Editor {
             RedrawEvent::ModeChange { mode_index } => self.cursor.change_mode(mode_index, &self.defined_styles),
             RedrawEvent::BusyStart => self.cursor.enabled = false,
             RedrawEvent::BusyStop => self.cursor.enabled = true,
-            RedrawEvent::Flush => REDRAW_SCHEDULER.request_redraw(),
+            RedrawEvent::Flush => REDRAW_SCHEDULER.queue_next_frame(),
             RedrawEvent::Resize { width, height, .. } => self.resize((width, height)),
             RedrawEvent::DefaultColorsSet { colors } => self.default_colors = colors,
             RedrawEvent::HighlightAttributesDefine { id, style } => { self.defined_styles.insert(id, style); },

src/redraw_scheduler.rs

@@ -1,44 +1,81 @@
 use std::sync::{Arc, Mutex};
-use std::time::Instant;
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::time::{Duration, Instant};
+use std::thread;
 
 use skulpin::winit::window::Window;
-use tokio::runtime::Runtime;
-use tokio::time::{Instant as TokioInstant, delay_until};
 
 lazy_static! {
     pub static ref REDRAW_SCHEDULER: RedrawScheduler = RedrawScheduler::new();
 }
 
 pub struct RedrawScheduler {
-    runtime: Runtime,
-    window: Mutex<Option<Arc<Window>>> // Swap to some atomic type
+    window: Mutex<Option<Arc<Window>>>, // Would prefer not to have to lock this every time.
+    frame_queued: AtomicBool,
+    scheduled_frame: Mutex<Option<Instant>>
+}
+
+pub fn redraw_loop() {
+    thread::spawn(|| {
+        loop {
+            let frame_start = Instant::now();
+
+            let request_redraw = {
+                if REDRAW_SCHEDULER.frame_queued.load(Ordering::Relaxed) {
+                    REDRAW_SCHEDULER.frame_queued.store(false, Ordering::Relaxed);
+                    true
+                } else {
+                    let mut next_scheduled_frame = REDRAW_SCHEDULER.scheduled_frame.lock().unwrap();
+                    if let Some(scheduled_frame) = next_scheduled_frame.clone() {
+                        if scheduled_frame < frame_start {
+                            *next_scheduled_frame = None;
+                            true
+                        } else {
+                            false
+                        }
+                    } else {
+                        false
+                    }
+                }
+            };
+
+            if request_redraw {
+                let window = REDRAW_SCHEDULER.window.lock().unwrap();
+                if let Some(window) = &*window {
+                    window.request_redraw();
+                }
+            }
+
+            if let Some(time_to_sleep) = Duration::from_secs_f32(1.0 / 60.0).checked_sub(Instant::now() - frame_start) {
+                thread::sleep(time_to_sleep)
+            }
+        }
+    });
 }
 
 impl RedrawScheduler {
     pub fn new() -> RedrawScheduler {
+        redraw_loop();
         RedrawScheduler { 
-            runtime: Runtime::new().unwrap(),
-            window: Mutex::new(None)
+            window: Mutex::new(None),
+            frame_queued: AtomicBool::new(false),
+            scheduled_frame: Mutex::new(None)
         }
     }
 
-    pub fn schedule(&self, time: Instant) {
-        let window = {
-            self.window.lock().unwrap().clone()
-        };
-
-        if let Some(window) = window {
-            self.runtime.spawn(async move {
-                delay_until(TokioInstant::from_std(time)).await;
-                window.request_redraw();
-            });
+    pub fn schedule(&self, new_scheduled: Instant) {
+        let mut scheduled_frame = self.scheduled_frame.lock().unwrap();
+        if let Some(previous_scheduled) = scheduled_frame.clone() {
+            if new_scheduled < previous_scheduled {
+                *scheduled_frame = Some(new_scheduled);
+            }
+        } else {
+            *scheduled_frame = Some(new_scheduled);
         }
     }
 
-    pub fn request_redraw(&self) {
-        if let Some(window) = self.window.lock().unwrap().as_ref() {
-            window.request_redraw();
-        }
+    pub fn queue_next_frame(&self) {
+        self.frame_queued.store(true, Ordering::Relaxed);
     }
 
     pub fn set_window(&self, window: &Arc<Window>){

src/renderer/cursor_renderer.rs

@@ -4,6 +4,7 @@ use skulpin::skia_safe::{Canvas, Paint, Path, Point};
 
 use crate::renderer::CachingShaper;
 use crate::editor::{EDITOR, Colors, Cursor, CursorShape};
+use crate::redraw_scheduler::REDRAW_SCHEDULER;
 
 const AVERAGE_MOTION_PERCENTAGE: f32 = 0.7;
 const MOTION_PERCENTAGE_SPREAD: f32 = 0.5;
@@ -33,7 +34,7 @@ impl BlinkStatus {
         }
     }
 
-    pub fn update_status(&mut self, new_cursor: &Cursor) -> (bool, Option<Instant>) {
+    pub fn update_status(&mut self, new_cursor: &Cursor) -> bool {
         if self.previous_cursor.is_none() || new_cursor != self.previous_cursor.as_ref().unwrap() {
             self.previous_cursor = Some(new_cursor.clone());
             self.last_transition = Instant::now();
@@ -47,7 +48,7 @@ impl BlinkStatus {
         if new_cursor.blinkwait == Some(0) || 
             new_cursor.blinkoff == Some(0) ||
             new_cursor.blinkon == Some(0) {
-            return (true, None);
+            return true;
         }
 
         let delay = match self.state {
@@ -65,17 +66,20 @@ impl BlinkStatus {
             self.last_transition = Instant::now();
         }
 
-        (
-            match self.state {
-                BlinkState::Waiting | BlinkState::Off => false,
-                BlinkState::On => true
-            }, 
-            (match self.state {
-                BlinkState::Waiting => new_cursor.blinkwait,
-                BlinkState::Off => new_cursor.blinkoff,
-                BlinkState::On => new_cursor.blinkon
-            }).map(|delay| self.last_transition + Duration::from_millis(delay))
-        )
+        let scheduled_frame = (match self.state {
+            BlinkState::Waiting => new_cursor.blinkwait,
+            BlinkState::Off => new_cursor.blinkoff,
+            BlinkState::On => new_cursor.blinkon
+        }).map(|delay| self.last_transition + Duration::from_millis(delay));
+
+        if let Some(scheduled_frame) = scheduled_frame {
+            REDRAW_SCHEDULER.schedule(scheduled_frame);
+        }
+
+        match self.state {
+            BlinkState::Waiting | BlinkState::Off => false,
+            BlinkState::On => true
+        }
     }
 }
 
@@ -171,8 +175,8 @@ impl CursorRenderer {
             cursor: Cursor, default_colors: &Colors, 
             font_width: f32, font_height: f32,
             paint: &mut Paint, shaper: &mut CachingShaper, 
-            canvas: &mut Canvas) -> (bool, Option<Instant>) {
-        let (render, scheduled_update) = self.blink_status.update_status(&cursor);
+            canvas: &mut Canvas) {
+        let render = self.blink_status.update_status(&cursor);
 
         self.previous_position = {
             let editor = EDITOR.lock().unwrap();
@@ -224,6 +228,10 @@ impl CursorRenderer {
             }
         }
 
+        if animating {
+            REDRAW_SCHEDULER.queue_next_frame();
+        }
+
         if cursor.enabled && render {
             // Draw Background
             paint.set_color(cursor.background(&default_colors).to_color());
@@ -240,7 +248,6 @@ impl CursorRenderer {
 
             // Draw foreground
             paint.set_color(cursor.foreground(&default_colors).to_color());
-            let editor = EDITOR.lock().unwrap();
             canvas.save();
             canvas.clip_path(&path, None, Some(false));
             
@@ -250,7 +257,5 @@ impl CursorRenderer {
             }
             canvas.restore();
         }
-
-        (animating, scheduled_update)
     }
 }

src/renderer/mod.rs

@@ -1,5 +1,3 @@
-use std::time::Instant;
-
 use skulpin::CoordinateSystemHelper;
 use skulpin::skia_safe::{Canvas, Paint, Surface, Budgeted, Rect, colors};
 use skulpin::skia_safe::gpu::SurfaceOrigin;
@@ -13,13 +11,6 @@ pub use caching_shaper::CachingShaper;
 use cursor_renderer::CursorRenderer;
 use crate::editor::{EDITOR, Style, Colors};
 
-#[derive(new)]
-pub struct DrawResult {
-    pub is_animating: bool,
-    pub font_changed: bool,
-    pub scheduled_update: Option<Instant>
-}
-
 pub struct Renderer {
     surface: Option<Surface>,
     paint: Paint,
@@ -105,7 +96,7 @@ impl Renderer {
         canvas.restore();
     }
 
-    pub fn draw(&mut self, gpu_canvas: &mut Canvas, coordinate_system_helper: &CoordinateSystemHelper) -> DrawResult {
+    pub fn draw(&mut self, gpu_canvas: &mut Canvas, coordinate_system_helper: &CoordinateSystemHelper) -> bool {
         let ((draw_commands, should_clear), default_colors, cursor, font_name, font_size) = {
             let mut editor = EDITOR.lock().unwrap();
             (
@@ -156,12 +147,12 @@ impl Renderer {
 
         self.surface = Some(surface);
 
-        let (cursor_animating, scheduled_cursor_update) = self.cursor_renderer.draw(
+        self.cursor_renderer.draw(
             cursor, &default_colors, 
             self.font_width, self.font_height, 
             &mut self.paint, &mut self.shaper,
             gpu_canvas);
 
-        DrawResult::new(!draw_commands.is_empty() || cursor_animating, font_changed, scheduled_cursor_update)
+        font_changed
     }
 }

src/window.rs

@@ -1,5 +1,5 @@
-use std::sync::{Arc, Mutex};
-use std::time::{Duration, Instant};
+use std::sync::Arc;
+use std::time::Instant;
 
 use image::{load_from_memory, GenericImageView, Pixel};
 use skulpin::{CoordinateSystem, RendererBuilder, PresentMode};
@@ -7,9 +7,9 @@ use skulpin::skia_safe::icu;
 use skulpin::winit::dpi::LogicalSize;
 use skulpin::winit::event::{ElementState, Event, MouseScrollDelta, StartCause, WindowEvent};
 use skulpin::winit::event_loop::{ControlFlow, EventLoop};
-use skulpin::winit::window::{Icon, Window, WindowBuilder};
+use skulpin::winit::window::{Icon, WindowBuilder};
 
-use crate::bridge::{construct_keybinding_string, BRIDGE, Bridge, UiCommand};
+use crate::bridge::{construct_keybinding_string, BRIDGE, UiCommand};
 use crate::renderer::Renderer;
 use crate::redraw_scheduler::REDRAW_SCHEDULER;
 use crate::INITIAL_DIMENSIONS;
@@ -18,8 +18,6 @@ use crate::INITIAL_DIMENSIONS;
 #[folder = "assets/"]
 struct Asset;
 
-const EXTRA_LIVE_FRAMES: usize = 10;
-
 fn handle_new_grid_size(new_size: LogicalSize, renderer: &Renderer) {
     if new_size.width > 0.0 && new_size.height > 0.0 {
         let new_width = ((new_size.width + 1.0) as f32 / renderer.font_width) as u64;
@@ -72,14 +70,9 @@ pub fn ui_loop() {
     let mut mouse_down = false;
     let mut mouse_pos = (0, 0);
 
-    let mut live_frames = 0;
-    let mut frame_start = Instant::now();
     event_loop.run(move |event, _window_target, control_flow| {
         match event {
-            Event::NewEvents(StartCause::Init) |
-            Event::NewEvents(StartCause::ResumeTimeReached { .. }) => {
-                window.request_redraw()
-            },
+            Event::NewEvents(StartCause::Init) => window.request_redraw(),
 
             Event::WindowEvent {
                 event: WindowEvent::CloseRequested,
@@ -90,7 +83,7 @@ pub fn ui_loop() {
                 event: WindowEvent::Resized(new_size),
                 ..
             } => {
-                handle_new_grid_size(window.inner_size(), &renderer)
+                handle_new_grid_size(new_size, &renderer)
             },
 
             Event::WindowEvent {
@@ -174,30 +167,12 @@ pub fn ui_loop() {
             }
 
             Event::RedrawRequested { .. }  => {
-                frame_start = Instant::now();
                 if let Err(e) = skulpin_renderer.draw(&window, |canvas, coordinate_system_helper| {
-                    let draw_result = renderer.draw(canvas, coordinate_system_helper);
-                    if draw_result.is_animating {
-                        live_frames = EXTRA_LIVE_FRAMES;
-                    } else {
-                        if live_frames > 0 {
-                            live_frames = live_frames - 1;
-                        }
-                    }
-
-                    if draw_result.font_changed {
+                    if renderer.draw(canvas, coordinate_system_helper) {
                         handle_new_grid_size(window.inner_size(), &renderer)
                     }
 
-                    if live_frames > 0 {
-                        *control_flow = ControlFlow::WaitUntil(frame_start + Duration::from_secs_f32(1.0 / 60.0));
-                    } else {
-                        *control_flow = ControlFlow::Wait;
-                    }
-
-                    if let Some(scheduled_update) = draw_result.scheduled_update {
-                        REDRAW_SCHEDULER.schedule(scheduled_update);
-                    }
+                    *control_flow = ControlFlow::Wait;
                 }) {
                     println!("Error during draw: {:?}", e);
                     *control_flow = ControlFlow::Exit