From 0a4a1af80ef8969278436943dd18196a91769ac6 Mon Sep 17 00:00:00 2001
From: rmschooley <rmschooley@att.net>
Date: Mon, 19 May 2025 06:03:33 -0500
Subject: [PATCH] Improve/Simplify Mouse Wheel Scroll Behavior (#470)

* Improve/Simplify Mouse Wheel Scroll Behavior

* Update hid_mouse_absolute.go

Attempt to fix line reported as improperly formatted by lint.

* Update utils.go

Removed abs() function since lint states it is no longer used.
---
 internal/usbgadget/hid_mouse_absolute.go | 16 ++++-----------
 internal/usbgadget/utils.go              |  8 --------
 ui/src/components/WebRTCVideo.tsx        | 26 ++++++++++++------------
 3 files changed, 17 insertions(+), 33 deletions(-)

diff --git a/internal/usbgadget/hid_mouse_absolute.go b/internal/usbgadget/hid_mouse_absolute.go
index 6629caa..b1c7428 100644
--- a/internal/usbgadget/hid_mouse_absolute.go
+++ b/internal/usbgadget/hid_mouse_absolute.go
@@ -107,24 +107,16 @@ func (u *UsbGadget) AbsMouseWheelReport(wheelY int8) error {
 	u.absMouseLock.Lock()
 	defer u.absMouseLock.Unlock()
 
-	// Accumulate the wheelY value
-	u.absMouseAccumulatedWheelY += float64(wheelY) / 8.0
-
-	// Only send a report if the accumulated value is significant
-	if abs(u.absMouseAccumulatedWheelY) < 1.0 {
+	// Only send a report if the value is non-zero
+	if wheelY == 0 {
 		return nil
 	}
 
-	scaledWheelY := int8(u.absMouseAccumulatedWheelY)
-
 	err := u.absMouseWriteHidFile([]byte{
-		2,                  // Report ID 2
-		byte(scaledWheelY), // Scaled Wheel Y (signed)
+		2,            // Report ID 2
+		byte(wheelY), // Wheel Y (signed)
 	})
 
-	// Reset the accumulator, keeping any remainder
-	u.absMouseAccumulatedWheelY -= float64(scaledWheelY)
-
 	u.resetUserInputTime()
 	return err
 }
diff --git a/internal/usbgadget/utils.go b/internal/usbgadget/utils.go
index 0e796c8..28a9e37 100644
--- a/internal/usbgadget/utils.go
+++ b/internal/usbgadget/utils.go
@@ -7,14 +7,6 @@ import (
 	"path/filepath"
 )
 
-// Helper function to get absolute value of float64
-func abs(x float64) float64 {
-	if x < 0 {
-		return -x
-	}
-	return x
-}
-
 func joinPath(basePath string, paths []string) string {
 	pathArr := append([]string{basePath}, paths...)
 	return filepath.Join(pathArr...)
diff --git a/ui/src/components/WebRTCVideo.tsx b/ui/src/components/WebRTCVideo.tsx
index 891555e..aa4a397 100644
--- a/ui/src/components/WebRTCVideo.tsx
+++ b/ui/src/components/WebRTCVideo.tsx
@@ -259,25 +259,25 @@ export default function WebRTCVideo() {
     (e: WheelEvent) => {
       if (blockWheelEvent) return;
 
-      // Determine if the wheel event is from a trackpad or a mouse wheel
-      const isTrackpad = Math.abs(e.deltaY) < trackpadThreshold;
+      // Determine if the wheel event is an accel scroll value
+      const isAccel = Math.abs(e.deltaY) >= 100;
 
-      // Apply appropriate sensitivity based on input device
-      const scrollSensitivity = isTrackpad ? trackpadSensitivity : mouseSensitivity;
+      // Calculate the accel scroll value
+      const accelScrollValue = e.deltaY / 100;
 
-      // Calculate the scroll value
-      const scroll = e.deltaY * scrollSensitivity;
+      // Calculate the no accel scroll value
+      const noAccelScrollValue = e.deltaY > 0 ? 1 : (e.deltaY < 0 ? -1 : 0);
 
-      // Apply clamping
-      const clampedScroll = Math.max(clampMin, Math.min(clampMax, scroll));
+      // Get scroll value
+      const scrollValue = isAccel ? accelScrollValue : noAccelScrollValue;
 
-      // Round to the nearest integer
-      const roundedScroll = Math.round(clampedScroll);
+      // Apply clamping (i.e. min and max mouse wheel hardware value)
+      const clampedScrollValue = Math.max(-127, Math.min(127, scrollValue));
 
-      // Invert the scroll value to match expected behavior
-      const invertedScroll = -roundedScroll;
+      // Invert the clamped scroll value to match expected behavior
+      const invertedScrollValue = -clampedScrollValue;
 
-      send("wheelReport", { wheelY: invertedScroll });
+      send("wheelReport", { wheelY : invertedScrollValue });
 
       // Apply blocking delay
       setBlockWheelEvent(true);