Improved input lag

* switched to sync_channel in WinitWindow
+ added framerate math (commented)
* improved gpu selection algorithm

main.rs

@@ -25,7 +25,7 @@ fn setup_logger() -> Result<(), fern::InitError> {
                 message
             ))
         })
-        .level(log::LevelFilter::Trace)
+        .level(log::LevelFilter::Debug)
         .chain(std::io::stdout())
         .chain(fern::log_file("output.log")?)
         .apply()?;

src/controller.rs

@@ -45,7 +45,7 @@ where
     }
 
     pub fn run(&mut self) {
-        use std::time::Duration;
+        use std::time::Duration; //, SystemTime};
 
         use crate::{
             subengine::subengine_controller::SubengineCommand,
@@ -56,6 +56,8 @@ where
         let mut input_keys: Vec<Key> = Vec::new(); 
 
         loop {
+//            let frame_start = SystemTime::now();
+
             for pipeline in &mut self.pipelines {
                 for input in &pipeline.inputs {
                     match input.borrow().read(Duration::from_millis(1)) {
@@ -114,6 +116,20 @@ where
                     };
                 };
             };
+
+//            let frame_time = SystemTime::now()
+//                .duration_since(frame_start)
+//                .unwrap();
+//            
+//            let sleep_time = Duration::from_secs_f32(1.0/60.0)
+//                .checked_sub(frame_time)
+//                .unwrap_or_else(|| {
+//                    info!("Engine overloaded !");
+//                    Duration::from_secs(0)
+//                });
+//            std::thread::sleep(sleep_time);
+//
+//            info!("FPS : {}", 1.0/frame_time.as_secs_f32());// + sleep_time.as_secs_f32()));
         }
     }
 }

src/io/winit_window.rs

@@ -61,7 +61,7 @@ impl WinitWindow {
         //Since we can't move the EventLoop from one thread to another, we need to create it in the
         //right thread and then move the Window back to the main thread instead
         let cloned_name = name.clone();
-        let (tx, rx) = mpsc::channel();
+        let (tx, rx) = mpsc::sync_channel(1);
         let (tmp_tx, tmp_rx) = mpsc::sync_channel(1);
         let builder = thread::Builder::new().name(title.into());
         //the EventLoop hijacks the thread so there is no need to join it later...
@@ -92,23 +92,25 @@ impl WinitWindow {
 
                 match event {
                     Event::LoopDestroyed => {
-                        let _ =  tx.send(Key::Closed).unwrap();
+                        tx.send(Key::Closed).unwrap();
                         debug!("Closed EventLoop");
                         return;
                     },
+
                     Event::WindowEvent{window_id: _, event} => match event {
                         event::WindowEvent::CloseRequested => {
                             debug!("Close requested");
-                            let _ = tx.send(Key::Close).unwrap();
+                            tx.send(Key::Close).unwrap();
                         },
                         event::WindowEvent::CursorMoved{position, ..} => {
-                                tx.send(Key::MouseMove{
+                                let _ = tx.try_send(Key::MouseMove{
                                     x: position.x,
                                     y: position.y,
-                                }).unwrap();
+                                });
                         },
                         _ => (),
                     },
+
                     Event::UserEvent(signal) => match signal {
                         Signal::Exit => {
                             debug!("Stopping input thread...");
@@ -118,6 +120,7 @@ impl WinitWindow {
                             tx.send(Key::Test).unwrap();
                         },
                     },
+
                     _ => (),
             }})
         });

src/renderer/gpu.rs

@@ -88,6 +88,7 @@ where
             use gfx_hal::{
                 Instance,
                 window::Surface,
+                adapter::DeviceType,
             };
 
             // dry run to print all adapters for debug purposes
@@ -103,7 +104,7 @@ where
             let adapter = instance
                 .enumerate_adapters()
                 .into_iter()
-                .find(|a| {
+                .filter(|a| {
                     a.queue_families
                         .iter()
                         .any(|qf|
@@ -113,7 +114,16 @@ where
                                 .all(|surface| 
                                      surface.supports_queue_family(&qf)
                 ))})
+                .max_by_key(|adapter| {
+                    match adapter.info.device_type {
+                        DeviceType::DiscreteGpu => 4, 
+                        DeviceType::IntegratedGpu => 3,
+                        DeviceType::VirtualGpu => 2, 
+                        DeviceType::Other => 1,
+                        DeviceType::Cpu => 0,
+                }})
                 .ok_or("Could not find a graphical adapter")?;
+
             info!("Selected adapter : {}", adapter.info.name);
 
             adapter