Changed the driver to have a lower sensitivity and to automatically stop a mt_scroll_event upon receiving no inputs for 100 ms. It restarts upon receiving new input afterwards.

Changes are implemented in fake_input.rs for the sensitivity change; and scroll_mt.rs for the debouncing behaviour.

src/controller/controls/scroll_mt.rs

@@ -2,14 +2,55 @@ use crate::controller::{ControlMode, ControlModeMeta};
 use crate::dial_device::DialHaptics;
 use crate::error::{Error, Result};
 use crate::fake_input;
+use std::sync::{Arc, Mutex};
+use std::thread::{self, JoinHandle};
+use std::time::{Duration, Instant};
 
 pub struct ScrollMT {
     acc_delta: i32,
+    last_dial_time: Arc<Mutex<Option<Instant>>>,
+    stop_thread: Arc<Mutex<bool>>,
+    is_scrolling: Arc<Mutex<bool>>,
+    timer_thread: Option<JoinHandle<()>>, // Add this to store the thread handle
 }
 
 impl ScrollMT {
     pub fn new() -> ScrollMT {
-        ScrollMT { acc_delta: 0 }
+        ScrollMT {
+            acc_delta: 0,
+            last_dial_time: Arc::new(Mutex::new(None)),
+            stop_thread: Arc::new(Mutex::new(false)),
+            is_scrolling: Arc::new(Mutex::new(false)),
+            timer_thread: None,
+        }
+    }
+
+    fn start_timer_thread(&mut self) {
+        // Reset the stop signal
+        *self.stop_thread.lock().unwrap() = false;
+
+        let last_dial_time = Arc::clone(&self.last_dial_time);
+        let stop_thread = Arc::clone(&self.stop_thread);
+        let is_scrolling = Arc::clone(&self.is_scrolling);
+
+        self.timer_thread = Some(thread::spawn(move || {
+            while !(*stop_thread.lock().unwrap()) {
+                thread::sleep(Duration::from_millis(100));
+
+                let mut last_time = last_dial_time.lock().unwrap();
+                let mut scrolling = is_scrolling.lock().unwrap();
+
+                if let Some(last) = *last_time {
+                    if last.elapsed() > Duration::from_millis(100) && *scrolling {
+                        if let Err(e) = fake_input::scroll_mt_end() {
+                            eprintln!("Error ending scroll: {:?}", e);
+                        }
+                        *last_time = None;
+                        *scrolling = false;
+                    }
+                }
+            }
+        }));
     }
 }
 
@@ -25,37 +66,60 @@ impl ControlMode for ScrollMT {
 
     fn on_start(&mut self, _haptics: &DialHaptics) -> Result<()> {
         self.acc_delta = 0;
+        *self.last_dial_time.lock().unwrap() = None;
+        *self.is_scrolling.lock().unwrap() = true;
 
-        // HACK: for some reason, if scroll mode is the startup mode, then just calling
-        // `scroll_mt_start` doesn't work as expected.
-        std::thread::spawn(move || {
-            fake_input::scroll_mt_end().unwrap();
-            std::thread::sleep(std::time::Duration::from_millis(200));
-            fake_input::scroll_mt_start().unwrap();
-        });
+        fake_input::scroll_mt_start().map_err(Error::Evdev)?;
+        
+        // Start a new timer thread
+        self.start_timer_thread();
 
         Ok(())
     }
 
     fn on_end(&mut self, _haptics: &DialHaptics) -> Result<()> {
+        // Signal the timer thread to stop
+        *self.stop_thread.lock().unwrap() = true;
+
+        // Wait for the timer thread to finish
+        if let Some(thread) = self.timer_thread.take() {
+            let _ = thread.join();
+        }
+
+        // End multitouch scrolling
         fake_input::scroll_mt_end().map_err(Error::Evdev)?;
         Ok(())
     }
 
-    // HACK: the button will reset the scroll event, which sometimes helps
-
     fn on_btn_press(&mut self, _: &DialHaptics) -> Result<()> {
+        // End multitouch scrolling on button press
         fake_input::scroll_mt_end().map_err(Error::Evdev)?;
+        *self.is_scrolling.lock().unwrap() = false;
         Ok(())
     }
 
     fn on_btn_release(&mut self, _haptics: &DialHaptics) -> Result<()> {
+        // Restart multitouch scrolling on button release
         fake_input::scroll_mt_start().map_err(Error::Evdev)?;
+        *self.is_scrolling.lock().unwrap() = true;
         Ok(())
     }
 
     fn on_dial(&mut self, _: &DialHaptics, delta: i32) -> Result<()> {
         self.acc_delta += delta;
+
+        // Update the last dial time
+        let mut last_dial_time = self.last_dial_time.lock().unwrap();
+        *last_dial_time = Some(Instant::now());
+
+        // Restart multitouch scrolling if it was inactive
+        let mut scrolling = self.is_scrolling.lock().unwrap();
+        if !*scrolling {
+            fake_input::scroll_mt_start().map_err(Error::Evdev)?;
+            *scrolling = true;
+        }
+
+        // Perform a multitouch scroll step
         fake_input::scroll_mt_step(self.acc_delta).map_err(Error::Evdev)?;
 
         Ok(())

src/fake_input.rs

@@ -7,7 +7,7 @@ use parking_lot::ReentrantMutex;
 // this should be a fairly high number, as the axis is from 0..(MT_BASELINE*2)
 const MT_BASELINE: i32 = std::i32::MAX / 8;
 // higher = slower scrolling
-const MT_SENSITIVITY: i32 = 48;
+const MT_SENSITIVITY: i32 = 32;
 
 pub struct FakeInputs {
     keyboard: ReentrantMutex<UInputDevice>,