Reviewing all the threeFingersDrag process fixes #1

ThreeFingersDragOnWindows.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <OutputType>Exe</OutputType>
+        <OutputType>WinExe</OutputType>
 <!--        TODO: switch to WinExe-->
         <TargetFramework>net6.0-windows</TargetFramework>
         <UseWindowsForms>true</UseWindowsForms>

src/touchpad/ContactsManager.cs

@@ -9,9 +9,10 @@ namespace ThreeFingersDragOnWindows.src.touchpad;
 public class ContactsManager<T> where T : Window, IContactsManager {
     private readonly List<TouchpadContact> _lastContacts = new();
     private readonly T _source;
-
     private HwndSource _targetSource;
 
+    private long _lastInput;
+
     public ContactsManager(T source){
         _source = source;
     }
@@ -45,14 +46,21 @@ private void RegisterTouchpadContact(TouchpadContact contact){
         foreach(var lastContact in _lastContacts)
             if(lastContact.ContactId == contact.ContactId){
                 // A contact is registered twice: send the event with the list of all contacts
-                _source.OnTouchpadContact(_lastContacts.ToArray());
+                if (Ctms() - _lastInput < 20){
+                    _source.OnTouchpadContact(_lastContacts.ToArray());
+                }
                 _lastContacts.Clear();
                 break;
             }
 
+        _lastInput = Ctms();
         // Add the contact to the list
         _lastContacts.Add(contact);
     }
+
+    private long Ctms(){
+        return new DateTimeOffset(DateTime.UtcNow).ToUnixTimeMilliseconds();
+    }
 }
 
 public interface IContactsManager {

src/touchpad/ThreeFingersDrag.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Timers;
+using Microsoft.VisualBasic.Devices;
 using ThreeFingersDragOnWindows.src.utils;
 
 namespace ThreeFingersDragOnWindows.src.touchpad;
@@ -9,18 +10,24 @@ public class ThreeFingersDrag {
     private readonly Timer _oneFingerTimer = new(20);
 
     private bool _isDragging;
-    private int _numberOfThreeFingersInputs = 0;
+
+    private ThreeFingersPoints _firstOneFingerPoints = ThreeFingersPoints.Empty;
+    private bool _isFirstOneFingerInput;
+    private long _firstOneFingerContact;
+    private long _lastOneFingerContact;
+
 
-    private ThreeFingersPoints _lastPoints = ThreeFingersPoints.Empty;
-    private MousePoint _lastOneFingerPoint = MousePoint.Empty;
+    private ThreeFingersPoints _lastThreeFingersPoints = ThreeFingersPoints.Empty;
+    private bool _isFirstThreeFingersInput;
     private long _firstThreeFingersContact;
     private long _lastThreeFingersContact;
+    private IntMousePoint _lastDragMousePoint = new IntMousePoint(0, 0);
 
     public ThreeFingersDrag(){
         // Setup timer
         _dragEndTimer.Elapsed += (_, _) => CheckDragEnd();
         _oneFingerTimer.Elapsed += (_, _) => {
-            if(Ctms() - _lastThreeFingersContact > 250){
+            if (Ctms() - _lastThreeFingersContact > 250){
                 stopDrag();
             }
         };
@@ -30,70 +37,85 @@ public ThreeFingersDrag(){
 
     public void OnTouchpadContact(TouchpadContact[] contacts){
         ThreeFingersPoints points = new(contacts);
-
-        if(contacts.Length == 3) {
-            if(_numberOfThreeFingersInputs == 0)  _firstThreeFingersContact = Ctms();
-            _numberOfThreeFingersInputs++;
+
+        if(contacts.Length == 3){
+            _isFirstOneFingerInput = true;
+            if(_isFirstThreeFingersInput){
+                _firstThreeFingersContact = Ctms();
+                _isFirstThreeFingersInput = false;
+            }
 
             if(!_isDragging){
-                if (Ctms() - _firstThreeFingersContact > 100) {
+                if (Ctms() - _firstThreeFingersContact > 100){ // When placing four fingers, a three fingers input can be detected for less than 100ms
                     _isDragging = true;
-                    MouseOperations.Click(true);   
+                    MouseOperations.Click(true);
                 }
-
             }else{
-                if(App.Prefs.ThreeFingersMove && _lastPoints != ThreeFingersPoints.Empty){
+                var dist2d = points.GetLongestDist2D(_lastThreeFingersPoints);
 
-                    var dist2d = points.GetLongestDist2D(_lastPoints);
+                if (App.Prefs.ThreeFingersMove // Three Fingers drag enabled in preferences
+                    && _lastThreeFingersPoints != ThreeFingersPoints.Empty // Last contact is a three fingers drag contact
+                    && Math.Sqrt(Math.Pow(dist2d.x, 2) + Math.Pow(dist2d.y, 2)) <= 30){ // Fingers can be released and replaced without catching any one/two finger contact. This makes sure the fingers haven't been replaced on the touchpad
+
                     float elapsed = _lastThreeFingersContact == 0 ? 0 : Ctms() - _lastThreeFingersContact;
+
                     // Apply the Mouse Speed preference
                     dist2d.Multiply(App.Prefs.MouseSpeed / 60);
-                    
+
                     // Calculate the mouse velocity
-                    var mouseVelocity = (float) Math.Max(0.2, Math.Min(dist2d.Length() / elapsed, 20));
-                    if(float.IsNaN(mouseVelocity) || float.IsInfinity(mouseVelocity)) mouseVelocity = 1;
+                    var mouseVelocity = (float)Math.Max(0.2, Math.Min(dist2d.Length() / elapsed, 20));
+                    if (float.IsNaN(mouseVelocity) || float.IsInfinity(mouseVelocity)) mouseVelocity = 1;
 
                     // Calculate the pointer velocity in function of the mouse velocity and the preference
-                    var pointerVelocity = (float) (App.Prefs.MouseAcceleration/10 * Math.Pow(mouseVelocity, 2) + 0.4 * mouseVelocity);
-                    pointerVelocity = (float) Math.Max(0.4, Math.Min(pointerVelocity, 1.6)); // Clamp
-                    if(App.Prefs.MouseAcceleration == 0) pointerVelocity = 1; // Disable acceleration
+                    var pointerVelocity = (float)(App.Prefs.MouseAcceleration / 10 * Math.Pow(mouseVelocity, 2) +
+                                                  0.4 * mouseVelocity);
+                    pointerVelocity = (float)Math.Max(0.4, Math.Min(pointerVelocity, 1.6)); // Clamp
+                    if (App.Prefs.MouseAcceleration == 0) pointerVelocity = 1; // Disable acceleration
                     // Apply acceleration
                     dist2d.Multiply(pointerVelocity);
 
                     MouseOperations.ShiftCursorPosition(dist2d.x, dist2d.y);
+
                 }
-
+
+                _lastDragMousePoint = MouseOperations.GetCursorPosition();
                 _dragEndTimer.Stop();
                 _dragEndTimer.Interval = GetReleaseDelay();
                 _dragEndTimer.Start();
             }
             _lastThreeFingersContact = Ctms();
-            _lastPoints = points;
-            _lastOneFingerPoint = MousePoint.Empty;
-
-        }else{
-            _numberOfThreeFingersInputs = 0;
-
-            if(!_isDragging) return;
-            MousePoint point = new MousePoint(contacts[0].X, contacts[0].Y);
+            _lastThreeFingersPoints = points; 
+        }
+        else{
+            _isFirstThreeFingersInput = true;
+            if (!_isDragging){
+                _isFirstOneFingerInput = true;
+                return;
+            }
+
+            if(_isFirstOneFingerInput || points.Length != _firstOneFingerPoints.Length || Ctms() - _lastOneFingerContact > 50){
+                _isFirstOneFingerInput = false;
+                _firstOneFingerContact = Ctms();
+                _firstOneFingerPoints = points;
+            }
 
-            if(!App.Prefs.AllowReleaseAndRestart) stopDrag();
-            // When releasing the fingers, one finger or two can be detected during some milliseconds.
-            else if(Ctms() - _lastThreeFingersContact > 50){
-                // Using a timer in case only one finger is detected when re-grabing the element
-                if(_oneFingerTimer.Enabled && _lastOneFingerPoint != MousePoint.Empty 
-                                           && point.DistTo(_lastOneFingerPoint)/MouseSpeedFactor() is < 50 and > 5){
-                    stopDrag();
-                }else _oneFingerTimer.Enabled = true;
+            if (!App.Prefs.AllowReleaseAndRestart) stopDrag();
+            else if (_firstOneFingerPoints.GetLongestDist(points) > 30){
+                // When RELEASING and then REPLACING the fingers, one finger or two can be detected and send some events.
+                stopDrag();
+            }
+            else{
+                MouseOperations.SetCursorPosition(_lastDragMousePoint.x, _lastDragMousePoint.y);
             }
-            _lastPoints = ThreeFingersPoints.Empty;
-            _lastOneFingerPoint = point;
+
+            _lastOneFingerContact = Ctms();
+            _lastThreeFingersPoints = ThreeFingersPoints.Empty;
         }
     }
 
     private void CheckDragEnd(){
         // minus 15 to avoid bugs when the timer ends before the time elapsed
-        if(_isDragging && Ctms() - _lastThreeFingersContact >= GetReleaseDelay()-15){  
+        if (_isDragging && Ctms() - _lastThreeFingersContact >= GetReleaseDelay() - 15){
             stopDrag();
         }
     }
@@ -102,7 +124,7 @@ private void stopDrag(){
         _isDragging = false;
         MouseOperations.Click(false);
     }
-    
+
     private int GetReleaseDelay(){
         return App.Prefs.AllowReleaseAndRestart ? Math.Max(App.Prefs.ReleaseDelay, 50) : 50;
     }

src/utils/MouseOperations.cs

@@ -50,10 +50,18 @@ public static void ShiftCursorPosition(float x, float y){
         var intY = (int) (y + _decimalY);
         _decimalX = (x + _decimalX) - intX;
         _decimalY = (y + _decimalY) - intY;
-        var point = GetCursorPosition();
 
         Move(intX, intY);
     }
+    public static void SetCursorPosition(float x, float y){
+        var intX = (int) (x + _decimalX);
+        var intY = (int) (y + _decimalY);
+        _decimalX = (x + _decimalX) - intX;
+        _decimalY = (y + _decimalY) - intY;
+        var point = GetCursorPosition();
+
+        Move(intX - point.x, intY - point.y);
+    }
 
     public static void Move(int dx, int dy) {
         MouseEvent(MouseOperations.MouseEventFlags.Move, dx, dy);

src/utils/Utils.cs

@@ -31,6 +31,10 @@ public MousePoint(float x, float y){
         this.x = x;
         this.y = y;
     }
+    public MousePoint(IntMousePoint point){
+        this.x = point.x;
+        this.y = point.y;
+    }
 
     public void Multiply(float multiplicator){
         x = x * multiplicator;
@@ -44,6 +48,9 @@ public float Length(){
     public float DistTo(MousePoint point){
         return (float) Math.Sqrt(Math.Pow(x - point.x, 2) + Math.Pow(y - point.y, 2));
     }
+    public float DistTo(IntMousePoint point){
+        return (float) Math.Sqrt(Math.Pow(x - point.x, 2) + Math.Pow(y - point.y, 2));
+    }
 
     public static MousePoint Empty = new(0, 0);
 
@@ -66,13 +73,15 @@ public IntMousePoint(int x, int y){
 }
 
 public struct ThreeFingersPoints {
+    public int Length;
     public float x1;
     public float y1;
     public float x2;
     public float y2;
     public float x3;
     public float y3;
     public ThreeFingersPoints(){
+        this.Length = 0;
         this.x1 = 0;
         this.y1 = 0;
         this.x2 = 0;
@@ -87,6 +96,13 @@ public ThreeFingersPoints(float x1, float y1, float x2, float y2, float x3, floa
         this.y2 = y2;
         this.x3 = x3;
         this.y3 = y3;
+        if (x1 == 0 && y1 == 0 && x2 == 0 && y2 == 0 && x3 == 0 && y3 == 0){
+            this.Length = 0;
+        }else if (x2 == 0 && y2 == 0 && x3 == 0 && y3 == 0){
+            this.Length = 1;
+        }else if (x3 == 0 && y3 == 0){
+            this.Length = 2;
+        }else this.Length = 3;
     }
     public ThreeFingersPoints(TouchpadContact[] contacts){
         if(contacts.Length >= 1){
@@ -110,9 +126,10 @@ public ThreeFingersPoints(TouchpadContact[] contacts){
             this.x3 = contacts[0].X;
             this.y3 = contacts[0].Y;
         }
+        this.Length = contacts.Length;
     }
-    public static ThreeFingersPoints Empty = new (0, 0, 0, 0, 0, 0);
-    
+    public static ThreeFingersPoints Empty = new();
+
     public static bool operator ==(ThreeFingersPoints a, ThreeFingersPoints b){
         return a.x1 == b.x1 && a.y1 == b.y1 && a.x2 == b.x2 && a.y2 == b.y2 && a.x3 == b.x3 && a.y3 == b.y3;
     }