Re-introduce the device manager, only fire keypress events if the key is held

src/device.rs

@@ -0,0 +1,34 @@
+use std::collections::HashMap;
+
+pub enum KeyEvent {
+    Pressed(u32),
+    Released(u32),
+}
+
+pub struct DeviceManager {
+    key_map: HashMap<u32, bool>,
+    key_event: Option<KeyEvent>,
+}
+
+impl DeviceManager {
+    pub fn new() -> Self {
+	DeviceManager {
+	    key_map: HashMap::new(),
+	    key_event: None
+	}
+    }
+    pub fn update_key_event(&mut self, scancode: u32, pressed: bool) {
+	let old = *self.key_map.get(&scancode).unwrap_or(&false);
+	if old != pressed {
+	    self.key_map.insert(scancode, pressed);
+	    if pressed {
+		self.key_event = Some(KeyEvent::Pressed(scancode));
+	    } else {
+		self.key_event = Some(KeyEvent::Released(scancode));
+	    }
+	}
+    }
+    pub fn handle_key_event(&mut self) -> Option<KeyEvent> {
+	std::mem::replace(&mut self.key_event, None)
+    }
+}

src/main.rs

@@ -1,3 +1,6 @@
+mod device;
+use device::*;
+
 mod model;
 use model::Model;
 
@@ -25,6 +28,8 @@ fn main() {
 
     let display = glium::Display::new(wb, cb, &events_loop).unwrap();
 
+    let mut device_manager = DeviceManager::new();
+
     let vertex_shader_src = include_str!("flat.vert");
     let fragment_shader_src = include_str!("flat.frag");
     let program = glium::Program::from_source(&display, vertex_shader_src, fragment_shader_src, None).unwrap();
@@ -63,9 +68,14 @@ fn main() {
 		    glutin::event::KeyboardInput { scancode, state, .. }
 		) = event {
 		    match state {
-			glutin::event::ElementState::Pressed => script_lang.key_pressed(scancode),
-			glutin::event::ElementState::Released => script_lang.key_released(scancode),
-		    }
+			glutin::event::ElementState::Pressed => device_manager.update_key_event(scancode, true),
+			glutin::event::ElementState::Released => device_manager.update_key_event(scancode, false),
+		    };
+		    match device_manager.handle_key_event() {
+			Some(KeyEvent::Pressed(x)) => script_lang.key_pressed(x),
+			Some(KeyEvent::Released(x)) => script_lang.key_released(x),
+			None => (),
+		    };
 		};
 	    },
 	    glutin::event::Event::MainEventsCleared => {