enable experimental smooth scrolling support

README.md

@@ -38,7 +38,7 @@ While the device-handling code itself is somewhat messy at the moment, it should
     - [x] Volume Controls
     - [x] Media Controls
     - [x] Scrolling - using a virtual mouse-wheel
-    - [ ] Scrolling - using a virtual touchpad (for [smoother scrolling](https://who-t.blogspot.com/2020/04/high-resolution-wheel-scrolling-in.html)) - **WIP**
+    - [x] Scrolling - using a virtual touchpad (for [smoother scrolling](https://who-t.blogspot.com/2020/04/high-resolution-wheel-scrolling-in.html)) - **EXPERIMENTAL**
     - [x] Zooming
     - [x] [Paddle](https://www.google.com/search?q=arkanoid+paddle) (emulated left, right, and space key)
     - [ ] \(meta\) custom modes specified via config file(s)

src/controller/controls/scroll_mt.rs

@@ -16,7 +16,7 @@ impl ScrollMT {
 impl ControlMode for ScrollMT {
     fn meta(&self) -> ControlModeMeta {
         ControlModeMeta {
-            name: "Scroll",
+            name: "Scroll (Fake Multitouch - EXPERIMENTAL)",
             icon: "input-mouse",
             haptics: false,
             steps: 3600,
@@ -26,7 +26,13 @@ impl ControlMode for ScrollMT {
     fn on_start(&mut self, _haptics: &DialHaptics) -> Result<()> {
         self.acc_delta = 0;
 
-        fake_input::scroll_mt_start().map_err(Error::Evdev)?;
+        // 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();
+        });
 
         Ok(())
     }

src/fake_input.rs

@@ -6,8 +6,8 @@ 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 = more sensitive
-const MT_SENSITIVITY: i32 = 64;
+// higher = slower scrolling
+const MT_SENSITIVITY: i32 = 48;
 
 pub struct FakeInputs {
     keyboard: ReentrantMutex<UInputDevice>,

src/main.rs

@@ -82,8 +82,8 @@ fn controller_main() -> Result<()> {
         dial,
         cfg.last_mode,
         vec![
-            // Box::new(controller::controls::ScrollMT::new()),
             Box::new(controller::controls::Scroll::new()),
+            Box::new(controller::controls::ScrollMT::new()),
             Box::new(controller::controls::Zoom::new()),
             Box::new(controller::controls::Volume::new()),
             Box::new(controller::controls::Media::new()),