wip trackpad

alt-tab-macos.xcodeproj/project.pbxproj

@@ -64,6 +64,7 @@
 		442E26DB1F7DA80AF794CCB6 /* Pods_unit_tests.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C7E6F409CA442F83B7BE71AD /* Pods_unit_tests.framework */; };
 		4807A6C623A9CD190052A53E /* SkyLight.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 4807A6C523A9CD190052A53E /* SkyLight.framework */; };
 		48F3E16224EC0D8800A1C64B /* Localizable.strings in Resources */ = {isa = PBXBuildFile; fileRef = D04BABDA79F8EF76E3ACDD5F /* Localizable.strings */; };
+		5883F0A829A5182C0071DB65 /* TrackpadEvents.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5883F0A729A5182C0071DB65 /* TrackpadEvents.swift */; };
 		5F21C9E02C6E94240091F72F /* ShortcutsWhenActiveSheet.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5F21C9DF2C6E94240091F72F /* ShortcutsWhenActiveSheet.swift */; };
 		5F21C9E22C6E94410091F72F /* AdditionalControlsSheet.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5F21C9E12C6E94410091F72F /* AdditionalControlsSheet.swift */; };
 		5F21C9E42C6E94700091F72F /* CustomizeStyleSheet.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5F21C9E32C6E94700091F72F /* CustomizeStyleSheet.swift */; };
@@ -324,6 +325,7 @@
 		1C961FB3DCF4906FEEF4A23D /* TableGroupView.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = TableGroupView.swift; sourceTree = "<group>"; };
 		4807A6C523A9CD190052A53E /* SkyLight.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = SkyLight.framework; path = ../../../../System/Library/PrivateFrameworks/SkyLight.framework; sourceTree = "<group>"; };
 		481FE54624D2D387001032F1 /* alt-tab-macos-Bridging-Header.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "alt-tab-macos-Bridging-Header.h"; sourceTree = "<group>"; };
+		5883F0A729A5182C0071DB65 /* TrackpadEvents.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TrackpadEvents.swift; sourceTree = "<group>"; };
 		59DD4BE63D42EEFF1182BA7F /* Pods-alt-tab-macos.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-alt-tab-macos.release.xcconfig"; path = "Target Support Files/Pods-alt-tab-macos/Pods-alt-tab-macos.release.xcconfig"; sourceTree = "<group>"; };
 		5F21C9DF2C6E94240091F72F /* ShortcutsWhenActiveSheet.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ShortcutsWhenActiveSheet.swift; sourceTree = "<group>"; };
 		5F21C9E12C6E94410091F72F /* AdditionalControlsSheet.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AdditionalControlsSheet.swift; sourceTree = "<group>"; };
@@ -1709,6 +1711,7 @@
 				D04BA76AEE37D6656EB80126 /* RunningApplicationsEvents.swift */,
 				D04BA5D9B4EBEB9E4333AE39 /* UserDefaultsEvents.swift */,
 				D04BAF320F4D43F0DDFE063E /* MouseEvents.swift */,
+				5883F0A729A5182C0071DB65 /* TrackpadEvents.swift */,
 				BF0C870C14C20C936BA4AF40 /* DockEvents.swift */,
 				BF0C8DF008F1EB5F23291A13 /* SpacesEvents.swift */,
 				BF0C822D3BEDAB1F1C9F775E /* ScreensEvents.swift */,
@@ -2226,6 +2229,7 @@
 				D04BA8757C9F20F25EB50785 /* TextField.swift in Sources */,
 				5F21C9E02C6E94240091F72F /* ShortcutsWhenActiveSheet.swift in Sources */,
 				D04BAE8B16A06A10E2FA94DE /* AccessibilityEvents.swift in Sources */,
+				5883F0A829A5182C0071DB65 /* TrackpadEvents.swift in Sources */,
 				D04BAAAF5CFA991D3B078DB8 /* KeyboardEvents.swift in Sources */,
 				D04BA1766FBCB2E941D081A5 /* RunningApplicationsEvents.swift in Sources */,
 				D04BA0AE9865276FF8EF5DEB /* UserDefaultsEvents.swift in Sources */,

resources/l10n/Localizable.strings

@@ -166,6 +166,9 @@
 /* No comment provided by engineer. */
 "Dark" = "Dark";
 
+/* No comment provided by engineer. */
+"Disabled" = "Disabled";
+
 /* No comment provided by engineer. */
 "Do nothing" = "Do nothing";
 
@@ -193,6 +196,9 @@
 /* No comment provided by engineer. */
 "General" = "General";
 
+/* No comment provided by engineer. */
+"Gesture" = "Gesture";
+
 /* Menubar callout button */
 "Grant permission" = "Grant permission";
 
@@ -289,6 +295,9 @@
 /* No comment provided by engineer. */
 "Open Screen Recording Preferences…" = "Open Screen Recording Preferences…";
 
+/* No comment provided by engineer. */
+"Open Trackpad Preferences…" = "Open Trackpad Preferences…";
+
 /* No comment provided by engineer. */
 "Optional: email (if you want a reply)" = "Optional: email (if you want a reply)";
 
@@ -475,6 +484,15 @@
 /* Menubar option */
 "Support this project ❤️" = "Support this project ❤️";
 
+/* No comment provided by engineer. */
+"Swipe may conflict with system shortcuts" = "Swipe may conflict with system shortcuts";
+
+/* No comment provided by engineer. */
+"Swipe with Four Fingers" = "Swipe with Four Fingers";
+
+/* No comment provided by engineer. */
+"Swipe with Three Fingers" = "Swipe with Three Fingers";
+
 /* No comment provided by engineer. */
 "Switch between 3 different styles. You can customize them." = "Switch between 3 different styles. You can customize them.";
 

src/logic/Preferences.swift

@@ -15,6 +15,7 @@ class Preferences {
         "nextWindowShortcut3": "",
         "nextWindowShortcut4": "",
         "nextWindowShortcut5": "",
+        "nextWindowGesture": GesturePreference.disabled.indexAsString,
         "focusWindowShortcut": "Space",
         "previousWindowShortcut": "⇧",
         "cancelShortcut": "⎋",
@@ -32,21 +33,25 @@ class Preferences {
         "showMinimizedWindows3": ShowHowPreference.show.indexAsString,
         "showMinimizedWindows4": ShowHowPreference.show.indexAsString,
         "showMinimizedWindows5": ShowHowPreference.show.indexAsString,
+        "showMinimizedWindows6": ShowHowPreference.show.indexAsString,
         "showHiddenWindows": ShowHowPreference.show.indexAsString,
         "showHiddenWindows2": ShowHowPreference.show.indexAsString,
         "showHiddenWindows3": ShowHowPreference.show.indexAsString,
         "showHiddenWindows4": ShowHowPreference.show.indexAsString,
         "showHiddenWindows5": ShowHowPreference.show.indexAsString,
+        "showHiddenWindows6": ShowHowPreference.show.indexAsString,
         "showFullscreenWindows": ShowHowPreference.show.indexAsString,
         "showFullscreenWindows2": ShowHowPreference.show.indexAsString,
         "showFullscreenWindows3": ShowHowPreference.show.indexAsString,
         "showFullscreenWindows4": ShowHowPreference.show.indexAsString,
         "showFullscreenWindows5": ShowHowPreference.show.indexAsString,
+        "showFullscreenWindows6": ShowHowPreference.show.indexAsString,
         "windowOrder": WindowOrderPreference.recentlyFocused.indexAsString,
         "windowOrder2": WindowOrderPreference.recentlyFocused.indexAsString,
         "windowOrder3": WindowOrderPreference.recentlyFocused.indexAsString,
         "windowOrder4": WindowOrderPreference.recentlyFocused.indexAsString,
         "windowOrder5": WindowOrderPreference.recentlyFocused.indexAsString,
+        "windowOrder6": WindowOrderPreference.recentlyFocused.indexAsString,
         "showTabsAsWindows": "false",
         "hideColoredCircles": "false",
         "windowDisplayDelay": "100",
@@ -65,16 +70,19 @@ class Preferences {
         "appsToShow3": AppsToShowPreference.all.indexAsString,
         "appsToShow4": AppsToShowPreference.all.indexAsString,
         "appsToShow5": AppsToShowPreference.all.indexAsString,
+        "appsToShow6": AppsToShowPreference.all.indexAsString,
         "spacesToShow": SpacesToShowPreference.all.indexAsString,
         "spacesToShow2": SpacesToShowPreference.all.indexAsString,
         "spacesToShow3": SpacesToShowPreference.all.indexAsString,
         "spacesToShow4": SpacesToShowPreference.all.indexAsString,
         "spacesToShow5": SpacesToShowPreference.all.indexAsString,
+        "spacesToShow6": SpacesToShowPreference.all.indexAsString,
         "screensToShow": ScreensToShowPreference.all.indexAsString,
         "screensToShow2": ScreensToShowPreference.all.indexAsString,
         "screensToShow3": ScreensToShowPreference.all.indexAsString,
         "screensToShow4": ScreensToShowPreference.all.indexAsString,
         "screensToShow5": ScreensToShowPreference.all.indexAsString,
+        "screensToShow6": ScreensToShowPreference.all.indexAsString,
         "fadeOutAnimation": "false",
         "hideSpaceNumberLabels": "false",
         "hideStatusIcons": "false",
@@ -90,6 +98,7 @@ class Preferences {
         "shortcutStyle3": ShortcutStylePreference.focusOnRelease.indexAsString,
         "shortcutStyle4": ShortcutStylePreference.focusOnRelease.indexAsString,
         "shortcutStyle5": ShortcutStylePreference.focusOnRelease.indexAsString,
+        "shortcutStyle6": ShortcutStylePreference.focusOnRelease.indexAsString,
         "hideAppBadges": "false",
         "hideWindowlessApps": "false",
         "hideThumbnails": "false",
@@ -106,6 +115,7 @@ class Preferences {
     // persisted values
     static var holdShortcut: [String] { ["holdShortcut", "holdShortcut2", "holdShortcut3", "holdShortcut4", "holdShortcut5"].map { UserDefaults.standard.string($0) } }
     static var nextWindowShortcut: [String] { ["nextWindowShortcut", "nextWindowShortcut2", "nextWindowShortcut3", "nextWindowShortcut4", "nextWindowShortcut5"].map { UserDefaults.standard.string($0) } }
+    static var nextWindowGesture: GesturePreference { UserDefaults.standard.macroPref("nextWindowGesture", GesturePreference.allCases) }
     static var focusWindowShortcut: String { UserDefaults.standard.string("focusWindowShortcut") }
     static var previousWindowShortcut: String { UserDefaults.standard.string("previousWindowShortcut") }
     static var cancelShortcut: String { UserDefaults.standard.string("cancelShortcut") }
@@ -148,14 +158,14 @@ class Preferences {
     static var showTitles: ShowTitlesPreference { UserDefaults.standard.macroPref("showTitles", ShowTitlesPreference.allCases) }
     static var updatePolicy: UpdatePolicyPreference { UserDefaults.standard.macroPref("updatePolicy", UpdatePolicyPreference.allCases) }
     static var crashPolicy: CrashPolicyPreference { UserDefaults.standard.macroPref("crashPolicy", CrashPolicyPreference.allCases) }
-    static var appsToShow: [AppsToShowPreference] { ["appsToShow", "appsToShow2", "appsToShow3", "appsToShow4", "appsToShow5"].map { UserDefaults.standard.macroPref($0, AppsToShowPreference.allCases) } }
+    static var appsToShow: [AppsToShowPreference] { ["appsToShow", "appsToShow2", "appsToShow3", "appsToShow4", "appsToShow5", "appsToShow6"].map { UserDefaults.standard.macroPref($0, AppsToShowPreference.allCases) } }
-    static var spacesToShow: [SpacesToShowPreference] { ["spacesToShow", "spacesToShow2", "spacesToShow3", "spacesToShow4", "spacesToShow5"].map { UserDefaults.standard.macroPref($0, SpacesToShowPreference.allCases) } }
+    static var spacesToShow: [SpacesToShowPreference] { ["spacesToShow", "spacesToShow2", "spacesToShow3", "spacesToShow4", "spacesToShow5", "spacesToShow6"].map { UserDefaults.standard.macroPref($0, SpacesToShowPreference.allCases) } }
-    static var screensToShow: [ScreensToShowPreference] { ["screensToShow", "screensToShow2", "screensToShow3", "screensToShow4", "screensToShow5"].map { UserDefaults.standard.macroPref($0, ScreensToShowPreference.allCases) } }
+    static var screensToShow: [ScreensToShowPreference] { ["screensToShow", "screensToShow2", "screensToShow3", "screensToShow4", "screensToShow5", "screensToShow6"].map { UserDefaults.standard.macroPref($0, ScreensToShowPreference.allCases) } }
-    static var showMinimizedWindows: [ShowHowPreference] { ["showMinimizedWindows", "showMinimizedWindows2", "showMinimizedWindows3", "showMinimizedWindows4", "showMinimizedWindows5"].map { UserDefaults.standard.macroPref($0, ShowHowPreference.allCases) } }
+    static var showMinimizedWindows: [ShowHowPreference] { ["showMinimizedWindows", "showMinimizedWindows2", "showMinimizedWindows3", "showMinimizedWindows4", "showMinimizedWindows5", "showMinimizedWindows6"].map { UserDefaults.standard.macroPref($0, ShowHowPreference.allCases) } }
-    static var showHiddenWindows: [ShowHowPreference] { ["showHiddenWindows", "showHiddenWindows2", "showHiddenWindows3", "showHiddenWindows4", "showHiddenWindows5"].map { UserDefaults.standard.macroPref($0, ShowHowPreference.allCases) } }
+    static var showHiddenWindows: [ShowHowPreference] { ["showHiddenWindows", "showHiddenWindows2", "showHiddenWindows3", "showHiddenWindows4", "showHiddenWindows5", "showHiddenWindows6"].map { UserDefaults.standard.macroPref($0, ShowHowPreference.allCases) } }
-    static var showFullscreenWindows: [ShowHowPreference] { ["showFullscreenWindows", "showFullscreenWindows2", "showFullscreenWindows3", "showFullscreenWindows4", "showFullscreenWindows5"].map { UserDefaults.standard.macroPref($0, ShowHowPreference.allCases) } }
+    static var showFullscreenWindows: [ShowHowPreference] { ["showFullscreenWindows", "showFullscreenWindows2", "showFullscreenWindows3", "showFullscreenWindows4", "showFullscreenWindows5", "showFullscreenWindows6"].map { UserDefaults.standard.macroPref($0, ShowHowPreference.allCases) } }
-    static var windowOrder: [WindowOrderPreference] { ["windowOrder", "windowOrder2", "windowOrder3", "windowOrder4", "windowOrder5"].map { UserDefaults.standard.macroPref($0, WindowOrderPreference.allCases) } }
+    static var windowOrder: [WindowOrderPreference] { ["windowOrder", "windowOrder2", "windowOrder3", "windowOrder4", "windowOrder5", "windowOrder6"].map { UserDefaults.standard.macroPref($0, WindowOrderPreference.allCases) } }
-    static var shortcutStyle: [ShortcutStylePreference] { ["shortcutStyle", "shortcutStyle2", "shortcutStyle3", "shortcutStyle4", "shortcutStyle5"].map { UserDefaults.standard.macroPref($0, ShortcutStylePreference.allCases) } }
+    static var shortcutStyle: [ShortcutStylePreference] { ["shortcutStyle", "shortcutStyle2", "shortcutStyle3", "shortcutStyle4", "shortcutStyle5", "shortcutStyle6"].map { UserDefaults.standard.macroPref($0, ShortcutStylePreference.allCases) } }
     static var menubarIcon: MenubarIconPreference { UserDefaults.standard.macroPref("menubarIcon", MenubarIconPreference.allCases) }
     static var menubarIconShown: Bool { UserDefaults.standard.bool("menubarIconShown") }
     static var language: LanguagePreference { UserDefaults.standard.macroPref("language", LanguagePreference.allCases) }
@@ -512,6 +522,20 @@ enum MenubarIconPreference: CaseIterable, MacroPreference {
     }
 }
 
+enum GesturePreference: CaseIterable, MacroPreference {
+    case disabled
+    case threeFingerSwipe
+    case fourFingerSwipe
+
+    var localizedString: LocalizedString {
+        switch self {
+            case .disabled: return NSLocalizedString("Disabled", comment: "")
+            case .threeFingerSwipe: return NSLocalizedString("Swipe with Three Fingers", comment: "")
+            case .fourFingerSwipe: return NSLocalizedString("Swipe with Four Fingers", comment: "")
+        }
+    }
+}
+
 enum LanguagePreference: CaseIterable, MacroPreference {
     case systemDefault
     case indonesian

src/logic/Windows.swift

@@ -182,10 +182,10 @@ class Windows {
         return list.count > focusedWindowIndex ? list[focusedWindowIndex] : nil
     }
 
-    static func cycleFocusedWindowIndex(_ step: Int) {
+    static func cycleFocusedWindowIndex(_ step: Int, allowWrap: Bool = true) {
         let nextIndex = windowIndexAfterCycling(step)
         if ((step > 0 && nextIndex < focusedWindowIndex) || (step < 0 && nextIndex > focusedWindowIndex)) &&
-               (ATShortcut.lastEventIsARepeat || KeyRepeatTimer.timer?.isValid ?? false) {
+               (!allowWrap || ATShortcut.lastEventIsARepeat || KeyRepeatTimer.timer?.isValid ?? false) {
             return
         }
         updateFocusedAndHoveredWindowIndex(nextIndex)

src/logic/events/TrackpadEvents.swift

@@ -0,0 +1,168 @@
+import Cocoa
+
+fileprivate var eventTap: CFMachPort!
+fileprivate var shouldBeEnabled: Bool!
+
+//TODO: Should we add a sensitivity setting instead of these magic numbers?
+fileprivate let SHOW_UI_THRESHOLD: Float = 0.003
+fileprivate let CYCLE_THRESHOLD: Float = 0.04
+
+// gesture tracking state
+fileprivate var prevTouchPositions: [String: NSPoint] = [:]
+fileprivate var totalDisplacement = (x: Float(0), y: Float(0))
+fileprivate var extendNextXThreshold = false
+
+//TODO: underlying content scrolls if both Mission Control and App Expose use 4-finger swipes or are off in Trackpad settings. It doesn't scroll if any of them use 3-finger swipe though.
+class TrackpadEvents {
+    static func observe() {
+        observe_()
+        TrackpadEvents.toggle(Preferences.nextWindowGesture != .disabled)
+    }
+
+    static func toggle(_ enabled: Bool) {
+        shouldBeEnabled = enabled
+        if let eventTap = eventTap {
+            CGEvent.tapEnable(tap: eventTap, enable: enabled)
+        }
+    }
+}
+
+private func observe_() {
+    // CGEvent.tapCreate returns null if ensureAccessibilityCheckboxIsChecked() didn't pass
+    eventTap = CGEvent.tapCreate(
+        tap: .cghidEventTap, // we need raw data
+        place: .headInsertEventTap,
+        options: .defaultTap,
+        eventsOfInterest: NSEvent.EventTypeMask.gesture.rawValue,
+        callback: handleEvent,
+        userInfo: nil)
+    if let eventTap = eventTap {
+        let runLoopSource = CFMachPortCreateRunLoopSource(nil, eventTap, 0)
+        CFRunLoopAddSource(BackgroundWork.keyboardEventsThread.runLoop, runLoopSource, .commonModes)
+    } else {
+        App.app.restart()
+    }
+}
+
+private let handleEvent: CGEventTapCallBack = { _, type, cgEvent, _ in
+    if type.rawValue == NSEvent.EventType.gesture.rawValue {
+        if touchEventHandler(cgEvent) {
+            return nil // focused app won't receive the event
+        }
+    } else if (type == .tapDisabledByUserInput || type == .tapDisabledByTimeout) && shouldBeEnabled {
+        CGEvent.tapEnable(tap: eventTap!, enable: true)
+    }
+    return Unmanaged.passUnretained(cgEvent) // focused app will receive the event
+}
+
+private func touchEventHandler(_ cgEvent: CGEvent) -> Bool {
+    var nsEvent: NSEvent?
+    DispatchQueue.main.sync {
+        nsEvent = NSEvent(cgEvent: cgEvent)
+    }
+    guard let nsEvent = nsEvent else { return false }
+    let touches = nsEvent.allTouches()
+    // Sometimes there are empty touch events that we have to skip. There are no empty touch events if Mission Control or App Expose use 3-finger swipes though.
+    if touches.isEmpty { return false }
+    let requiredFingers = Preferences.nextWindowGesture == .fourFingerSwipe ? 4 : 3
+    if touches.allSatisfy({ $0.phase == .ended }) || touches.count != requiredFingers {
+        clearState()
+        if App.app.appIsBeingUsed && touches.count < requiredFingers && App.app.shortcutIndex == 5
+            && Preferences.shortcutStyle[App.app.shortcutIndex] == .focusOnRelease {
+            DispatchQueue.main.async { App.app.focusTarget() }
+            return true
+        }
+        return false
+    }
+
+    guard let delta = calculateTouchDelta(touches) else { return false }
+    let displacement = (x: totalDisplacement.x + delta.x, y: totalDisplacement.y + delta.y)
+    totalDisplacement = displacement
+
+    // handle showing the app initially
+    if !App.app.appIsBeingUsed {
+        if abs(displacement.x) > SHOW_UI_THRESHOLD && abs(displacement.y) < SHOW_UI_THRESHOLD {
+            resetDisplacement(x: true, y: false)
+            // the SHOW_UI_THRESHOLD is much less then the CYCLE_THRESHOLD
+            // so for consistency when swiping, extend the threshold for the next horizontal swipe
+            extendNextXThreshold = true
+            DispatchQueue.main.async { App.app.showUiOrCycleSelection(5) }
+            return true
+        }
+        return false
+    }
+
+    // handle swipes when the app is open
+    if abs(displacement.x) > CYCLE_THRESHOLD {
+        // if extendNextXThreshold is set, extend the threshold for a right swipe to account for the show ui swipe
+        if !extendNextXThreshold || displacement.x < 0
+            || displacement.x > 2 * CYCLE_THRESHOLD - SHOW_UI_THRESHOLD
+        {
+            let direction: Direction = displacement.x < 0 ? .left : .right
+            resetDisplacement(x: true, y: false)
+            extendNextXThreshold = false
+        DispatchQueue.main.async { App.app.cycleSelection(direction, allowWrap: false) }
+        return true
+        }
+    }
+    if abs(displacement.y) > CYCLE_THRESHOLD {
+        let direction: Direction = displacement.y < 0 ? .down : .up
+        resetDisplacement(x: false, y: true)
+        DispatchQueue.main.async { App.app.cycleSelection(direction, allowWrap: false) }
+        return true
+    }
+    return false
+}
+
+private func calculateTouchDelta(_ touches: Set<NSTouch>) -> (x: Float, y: Float)? {
+    var allRight = true
+    var allLeft = true
+    var allUp = true
+    var allDown = true
+    var sumDelta = (x: Float(0), y: Float(0))
+    var count = 0
+
+    for touch in touches {
+        let prevPosition = prevTouchPositions["\(touch.identity)"]
+        let position = touch.normalizedPosition
+        if touch.phase == .ended {
+            prevTouchPositions.removeValue(forKey: "\(touch.identity)")
+        } else {
+            prevTouchPositions["\(touch.identity)"] = position
+        }
+        if prevPosition == nil { continue }
+
+        let delta = (
+            x: Float(position.x - prevPosition!.x), y: Float(position.y - prevPosition!.y)
+        )
+
+        allRight = allRight && delta.x > 0
+        allLeft = allLeft && delta.x < 0
+        allUp = allUp && delta.y > 0
+        allDown = allDown && delta.y < 0
+
+        sumDelta.x += delta.x
+        sumDelta.y += delta.y
+        count += 1
+    }
+
+    // All fingers should move in the same direction.
+    if count == 0 || (!allRight && !allLeft && !allUp && !allDown) { return nil }
+    return (x: sumDelta.x / Float(count), y: sumDelta.y / Float(count))
+}
+
+private func clearState() {
+    prevTouchPositions.removeAll()
+    resetDisplacement()
+    extendNextXThreshold = false
+}
+
+private func resetDisplacement(x: Bool = true, y: Bool = true) {
+    if x && y {
+        totalDisplacement = (0, 0)
+    } else if x {
+        totalDisplacement.x = 0
+    } else if y {
+        totalDisplacement.y = 0
+    }
+}

src/ui/App.swift

@@ -74,6 +74,7 @@ class App: AppCenterApplication, NSApplicationDelegate {
             self.feedbackWindow = FeedbackWindow()
             KeyboardEvents.addEventHandlers()
             MouseEvents.observe()
+            TrackpadEvents.observe()
             // TODO: undeterministic; events in the queue may still be processing; good enough for now
             DispatchQueue.main.async { () -> () in Windows.sortByLevel() }
             self.preloadWindows()
@@ -216,11 +217,11 @@ class App: AppCenterApplication, NSApplicationDelegate {
         showPreferencesWindow()
     }
 
-    func cycleSelection(_ direction: Direction) {
+    func cycleSelection(_ direction: Direction, allowWrap: Bool = true) {
         if direction == .up || direction == .down {
-            thumbnailsPanel.thumbnailsView.navigateUpOrDown(direction)
+            thumbnailsPanel.thumbnailsView.navigateUpOrDown(direction, allowWrap: allowWrap)
         } else {
-            Windows.cycleFocusedWindowIndex(direction.step())
+            Windows.cycleFocusedWindowIndex(direction.step(), allowWrap: allowWrap)
         }
     }
 

src/ui/main-window/ThumbnailsView.swift

@@ -57,24 +57,32 @@ class ThumbnailsView: NSVisualEffectView {
         }
     }
 
-    func nextRow(_ direction: Direction) -> [ThumbnailView]? {
+    func nextRow(_ direction: Direction, allowWrap: Bool = true) -> [ThumbnailView]? {
         let step = direction == .down ? 1 : -1
         if let currentRow = Windows.focusedWindow()?.rowIndex {
-            let nextRow = (currentRow + step) % rows.count
+            var nextRow = currentRow + step
-            let nextRow_ = nextRow < 0 ? rows.count + nextRow : nextRow
+            if nextRow >= rows.count {
-            if ((step > 0 && nextRow_ < currentRow) || (step < 0 && nextRow_ > currentRow)) &&
+                if allowWrap {
+                    nextRow = nextRow % rows.count
+                } else { return nil }
+            } else if nextRow < 0 {
+                if allowWrap {
+                    nextRow = rows.count + nextRow
+                } else { return nil }
+            }
+            if ((step > 0 && nextRow < currentRow) || (step < 0 && nextRow > currentRow)) &&
                    (ATShortcut.lastEventIsARepeat || KeyRepeatTimer.timer?.isValid ?? false) {
                 return nil
             }
-            return rows[nextRow_]
+            return rows[nextRow]
         }
         return nil
     }
 
-    func navigateUpOrDown(_ direction: Direction) {
+    func navigateUpOrDown(_ direction: Direction, allowWrap: Bool = true) {
         let focusedViewFrame = ThumbnailsView.recycledViews[Windows.focusedWindowIndex].frame
         let originCenter = NSMidX(focusedViewFrame)
-        if let targetRow = nextRow(direction) {
+        if let targetRow = nextRow(direction, allowWrap: allowWrap) {
             let leftSide = originCenter < NSMidX(frame)
             let leadingSide = App.shared.userInterfaceLayoutDirection == .leftToRight ? leftSide : !leftSide
             let iterable = leadingSide ? targetRow : targetRow.reversed()

src/ui/preferences-window/tabs/controls/ControlsTab.swift

@@ -41,12 +41,13 @@ class ControlsTab {
     static var additionalControlsSheet: AdditionalControlsSheet!
 
     static func initTab() -> NSView {
-        let (holdShortcut, nextWindowShortcut, tab1View) = toShowSection(0)
+        let (holdShortcut, nextWindowShortcut, tab1View) = shortcutTab(0)
-        let (holdShortcut2, nextWindowShortcut2, tab2View) = toShowSection(1)
+        let (holdShortcut2, nextWindowShortcut2, tab2View) = shortcutTab(1)
-        let (holdShortcut3, nextWindowShortcut3, tab3View) = toShowSection(2)
+        let (holdShortcut3, nextWindowShortcut3, tab3View) = shortcutTab(2)
-        let (holdShortcut4, nextWindowShortcut4, tab4View) = toShowSection(3)
+        let (holdShortcut4, nextWindowShortcut4, tab4View) = shortcutTab(3)
-        let (holdShortcut5, nextWindowShortcut5, tab5View) = toShowSection(4)
+        let (holdShortcut5, nextWindowShortcut5, tab5View) = shortcutTab(4)
-        tableGroupViews = [tab1View, tab2View, tab3View, tab4View, tab5View]
+        let tab6View = gestureTab(5)
+        tableGroupViews = [tab1View, tab2View, tab3View, tab4View, tab5View, tab6View]
         // trigger shortcutChanged for these shortcuts to trigger .restrictModifiers
         [holdShortcut, holdShortcut2, holdShortcut3, holdShortcut4, holdShortcut5].forEach { ControlsTab.shortcutChangedCallback($0[1] as! NSControl) }
         [nextWindowShortcut, nextWindowShortcut2, nextWindowShortcut3, nextWindowShortcut4, nextWindowShortcut5].forEach { ControlsTab.shortcutChangedCallback($0[0] as! NSControl) }
@@ -62,6 +63,7 @@ class ControlsTab {
             NSLocalizedString("Shortcut 3", comment: ""),
             NSLocalizedString("Shortcut 4", comment: ""),
             NSLocalizedString("Shortcut 5", comment: ""),
+            NSLocalizedString("Gesture", comment: ""),
         ], trackingMode: .selectOne, target: self, action: #selector(switchTab(_:)))
         tab.selectedSegment = 0
         tab.segmentStyle = .automatic
@@ -71,7 +73,7 @@ class ControlsTab {
         let additionalControlsButton = NSButton(title: NSLocalizedString("Additional controls…", comment: ""), target: self, action: #selector(ControlsTab.showAdditionalControlsSettings))
         let shortcutsButton = NSButton(title: NSLocalizedString("Shortcuts when active…", comment: ""), target: self, action: #selector(ControlsTab.showShortcutsSettings))
         let tools = StackView([additionalControlsButton, shortcutsButton], .horizontal)
-        let view = TableGroupSetView(originalViews: [table, tab1View, tab2View, tab3View, tab4View, tab5View], toolsViews: [tools], toolsAlignment: .trailing)
+        let view = TableGroupSetView(originalViews: [table, tab1View, tab2View, tab3View, tab4View, tab5View, tab6View], toolsViews: [tools], toolsAlignment: .trailing)
         view.translatesAutoresizingMaskIntoConstraints = false
 
         shortcutsWhenActiveSheet = ShortcutsWhenActiveSheet()
@@ -82,7 +84,28 @@ class ControlsTab {
         return view
     }
 
-    private static func toShowSection(_ index: Int) -> ([NSView], [NSView], TableGroupView) {
+    private static func shortcutTab(_ index: Int) -> ([NSView], [NSView], TableGroupView) {
+        var holdShortcut = LabelAndControl.makeLabelWithRecorder(NSLocalizedString("Hold", comment: ""), Preferences.indexToName("holdShortcut", index), Preferences.holdShortcut[index], false, labelPosition: .leftWithoutSeparator)
+        holdShortcut.append(LabelAndControl.makeLabel(NSLocalizedString("and press", comment: "")))
+        let nextWindowShortcut = LabelAndControl.makeLabelWithRecorder(NSLocalizedString("Select next window", comment: ""), Preferences.indexToName("nextWindowShortcut", index), Preferences.nextWindowShortcut[index], labelPosition: .right)
+        let tab = controlTab(index, holdShortcut + [nextWindowShortcut[0]])
+        return (holdShortcut, nextWindowShortcut, tab)
+    }
+
+    private static func gestureTab(_ index: Int) -> TableGroupView {
+        let label = NSLocalizedString("Swipe may conflict with system shortcuts", comment: "")
+        let button = NSButton(title: NSLocalizedString("Open Trackpad Preferences…", comment: ""), target: self, action: #selector(openSystemGestures(_:)))
+        let infoBtn = LabelAndControl.makeInfoButton(onMouseEntered: { event, view in
+            Popover.shared.show(event: event, positioningView: view, message: label, extraView: button)
+        })
+        let gesture = LabelAndControl.makeDropdown("nextWindowGesture", GesturePreference.allCases, extraAction: ControlsTab.gestureChangedCallback)
+        let gestureWithTooltip = StackView([infoBtn, gesture], .horizontal)
+        gestureWithTooltip.spacing = 8
+        gestureWithTooltip.alignment = .centerY
+        return controlTab(index, [gestureWithTooltip])
+    }
+
+    private static func controlTab(_ index: Int, _ trigger: [NSView]) -> TableGroupView {
         let appsToShow = LabelAndControl.makeDropdown(Preferences.indexToName("appsToShow", index), AppsToShowPreference.allCases)
         let spacesToShow = LabelAndControl.makeDropdown(Preferences.indexToName("spacesToShow", index), SpacesToShowPreference.allCases)
         let screensToShow = LabelAndControl.makeDropdown(Preferences.indexToName("screensToShow", index), ScreensToShowPreference.allCases)
@@ -90,14 +113,10 @@ class ControlsTab {
         let showHiddenWindows = LabelAndControl.makeDropdown(Preferences.indexToName("showHiddenWindows", index), ShowHowPreference.allCases)
         let showFullscreenWindows = LabelAndControl.makeDropdown(Preferences.indexToName("showFullscreenWindows", index), ShowHowPreference.allCases.filter { $0 != .showAtTheEnd })
         let windowOrder = LabelAndControl.makeDropdown(Preferences.indexToName("windowOrder", index), WindowOrderPreference.allCases)
-
-        var holdShortcut = LabelAndControl.makeLabelWithRecorder(NSLocalizedString("Hold", comment: ""), Preferences.indexToName("holdShortcut", index), Preferences.holdShortcut[index], false, labelPosition: .leftWithoutSeparator)
-        holdShortcut.append(LabelAndControl.makeLabel(NSLocalizedString("and press", comment: "")))
-        let nextWindowShortcut = LabelAndControl.makeLabelWithRecorder(NSLocalizedString("Select next window", comment: ""), Preferences.indexToName("nextWindowShortcut", index), Preferences.nextWindowShortcut[index], labelPosition: .right)
         let shortcutStyle = LabelAndControl.makeDropdown(Preferences.indexToName("shortcutStyle", index), ShortcutStylePreference.allCases)
 
         let table = TableGroupView(width: PreferencesWindow.width)
-        table.addRow(TableGroupView.Row(leftTitle: NSLocalizedString("Trigger shortcut", comment: ""), rightViews: holdShortcut + [nextWindowShortcut[0]]))
+        table.addRow(TableGroupView.Row(leftTitle: NSLocalizedString("Trigger shortcut", comment: ""), rightViews: trigger))
         table.addRow(TableGroupView.Row(leftTitle: NSLocalizedString("After release", comment: ""), rightViews: [shortcutStyle]))
 
         table.addNewTable()
@@ -109,7 +128,7 @@ class ControlsTab {
         table.addRow(TableGroupView.Row(leftTitle: NSLocalizedString("Show fullscreen windows", comment: ""), rightViews: [showFullscreenWindows]))
         table.addRow(TableGroupView.Row(leftTitle: NSLocalizedString("Order windows by", comment: ""), rightViews: [windowOrder]))
         table.fit()
-        return (holdShortcut, nextWindowShortcut, table)
+        return table
     }
 
     @objc static func switchTab(_ sender: NSSegmentedControl) {
@@ -293,6 +312,15 @@ class ControlsTab {
         }
     }
 
+    @objc static func gestureChangedCallback(_ sender: NSControl) {
+        TrackpadEvents.toggle(Preferences.nextWindowGesture != .disabled)
+    }
+
+    @objc private static func openSystemGestures(_ sender: NSButton) {
+        // Apple doesn't expose the More Gestures tab directly
+        NSWorkspace.shared.open(URL(string: "x-apple.systempreferences:com.apple.Trackpad-Settings.extension")!)
+    }
+
     static func executeAction(_ action: String) {
         shortcutsActions[action]!()
     }