Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 8a22cd58 authored by Michal Brzezinski's avatar Michal Brzezinski
Browse files

Refactoring gesture recognition logic 

1/n of introducing gesture live progress tracking

Main motivation for refactoring is making gesture recognition more composition-friendly and extendable, currently ThreeFingerDistanceBasedGestureMonitor is counter-example of that. Goal is to easily filter by number of gestures and react on distance changes and - in the future - to velocity at the end. And to be able to have any combination of that.
Also I think the new code is easier to understand because we avoid inheritance.

Incoming further changes:
- Rename *GestureMonitor to *GestureRecognizer
- Refactor Recent apps gesture logic to follow similar design of compositing features

Bug: 369817369
Test: All tests are passing
Flag: com.android.systemui.shared.new_touchpad_gestures_tutorial
Change-Id: I690b8a95d93a4a18f41ade98e4b214d14153cd6a
parent 88dcc78c

packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/BackGestureMonitor.kt

+17 −19
Original line number Diff line number Diff line
@@ -16,26 +16,24 @@ 


package com.android.systemui.touchpad.tutorial.ui.gesture



import android.view.MotionEvent

import kotlin.math.abs



/** Monitors for touchpad back gesture, that is three fingers swiping left or right */

class BackGestureMonitor(

    override val gestureDistanceThresholdPx: Int,

    override val gestureStateChangedCallback: (GestureState) -> Unit

) :

    TouchpadGestureMonitor by ThreeFingerDistanceBasedGestureMonitor(

        gestureDistanceThresholdPx = gestureDistanceThresholdPx,

        gestureStateChangedCallback = gestureStateChangedCallback,

        donePredicate =

            object : GestureDonePredicate {

                override fun wasGestureDone(

                    startX: Float,

                    startY: Float,

                    endX: Float,

                    endY: Float

                ): Boolean {

                    val distance = abs(endX - startX)

                    return distance >= gestureDistanceThresholdPx

    private val gestureDistanceThresholdPx: Int,

    override val gestureStateChangedCallback: (GestureState) -> Unit,

) : TouchpadGestureMonitor {

    private val distanceTracker = DistanceTracker()



    override fun processTouchpadEvent(event: MotionEvent) {

        if (!isThreeFingerTouchpadSwipe(event)) return

        val distanceState = distanceTracker.processEvent(event)

        updateGestureStateBasedOnDistance(

            gestureStateChangedCallback,

            distanceState,

            isFinished = { abs(it.deltaX) >= gestureDistanceThresholdPx },

            progress = { 0f },

        )

    }

}
 
    )

packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/ThreeFingerDistanceBasedGestureMonitor.kt→packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/DistanceTracker.kt

+47 −0
Original line number Diff line number Diff line
@@ -18,46 +18,30 @@ package com.android.systemui.touchpad.tutorial.ui.gesture 


import android.view.MotionEvent



interface GestureDonePredicate {

/**

     * Should return if gesture was finished. The only events this predicate receives are ACTION_UP.

 * Tracks distance change for processed MotionEvents. Useful for recognizing gestures based on

 * distance travelled instead of specific position on the screen.

 */

    fun wasGestureDone(startX: Float, startY: Float, endX: Float, endY: Float): Boolean

}



/**

 * Common implementation for three-finger gesture monitors that are only distance-based. E.g. recent

 * apps gesture is not only distance-based because it requires going over threshold distance and

 * slowing down the movement.

 */

class ThreeFingerDistanceBasedGestureMonitor(

    override val gestureDistanceThresholdPx: Int,

    override val gestureStateChangedCallback: (GestureState) -> Unit,

    private val donePredicate: GestureDonePredicate

) : TouchpadGestureMonitor {



    private var xStart = 0f

    private var yStart = 0f



    override fun processTouchpadEvent(event: MotionEvent) {

class DistanceTracker(var startX: Float = 0f, var startY: Float = 0f) {

    fun processEvent(event: MotionEvent): DistanceGestureState? {

        val action = event.actionMasked

        when (action) {

        return when (action) {

            MotionEvent.ACTION_DOWN -> {

                if (isThreeFingerTouchpadSwipe(event)) {

                    xStart = event.x

                    yStart = event.y

                    gestureStateChangedCallback(GestureState.InProgress())

                }

            }

            MotionEvent.ACTION_UP -> {

                if (isThreeFingerTouchpadSwipe(event)) {

                    if (donePredicate.wasGestureDone(xStart, yStart, event.x, event.y)) {

                        gestureStateChangedCallback(GestureState.Finished)

                    } else {

                        gestureStateChangedCallback(GestureState.NotStarted)

                    }

                }

                startX = event.x

                startY = event.y

                Started(event.x, event.y)

            }

            MotionEvent.ACTION_MOVE -> Moving(event.x - startX, event.y - startY)

            MotionEvent.ACTION_UP -> Finished(event.x - startX, event.y - startY)

            else -> null

        }

    }

}



sealed interface DistanceGestureState



class Started(val deltaX: Float, val deltaY: Float) : DistanceGestureState



class Moving(val deltaX: Float, val deltaY: Float) : DistanceGestureState



class Finished(val deltaX: Float, val deltaY: Float) : DistanceGestureState

packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/GestureStateUpdates.kt

0 → 100644
+43 −0
Original line number Diff line number Diff line 
/*

 * Copyright (C) 2024 The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */



package com.android.systemui.touchpad.tutorial.ui.gesture



/**

 * Helper function for gesture recognizers to have common state triggering logic based on distance

 * only.

 */

inline fun updateGestureStateBasedOnDistance(

    gestureStateChangedCallback: (GestureState) -> Unit,

    gestureState: DistanceGestureState?,

    isFinished: (Finished) -> Boolean,

    progress: (Moving) -> Float,

) {

    when (gestureState) {

        is Finished -> {

            if (isFinished(gestureState)) {

                gestureStateChangedCallback(GestureState.Finished)

            } else {

                gestureStateChangedCallback(GestureState.NotStarted)

            }

        }

        is Moving -> {

            gestureStateChangedCallback(GestureState.InProgress(progress(gestureState)))

        }

        is Started -> gestureStateChangedCallback(GestureState.InProgress())

        else -> {}

    }

}

packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/HomeGestureMonitor.kt

+18 −19
Original line number Diff line number Diff line
@@ -16,24 +16,23 @@ 


package com.android.systemui.touchpad.tutorial.ui.gesture



import android.view.MotionEvent



/** Monitors for touchpad home gesture, that is three fingers swiping up */

class HomeGestureMonitor(

    override val gestureDistanceThresholdPx: Int,

    override val gestureStateChangedCallback: (GestureState) -> Unit

) :

    TouchpadGestureMonitor by ThreeFingerDistanceBasedGestureMonitor(

        gestureDistanceThresholdPx = gestureDistanceThresholdPx,

        gestureStateChangedCallback = gestureStateChangedCallback,

        donePredicate =

            object : GestureDonePredicate {

                override fun wasGestureDone(

                    startX: Float,

                    startY: Float,

                    endX: Float,

                    endY: Float

                ): Boolean {

                    val distance = startY - endY

                    return distance >= gestureDistanceThresholdPx

    private val gestureDistanceThresholdPx: Int,

    override val gestureStateChangedCallback: (GestureState) -> Unit,

) : TouchpadGestureMonitor {

    private val distanceTracker = DistanceTracker()



    override fun processTouchpadEvent(event: MotionEvent) {

        if (!isThreeFingerTouchpadSwipe(event)) return

        val distanceState = distanceTracker.processEvent(event)

        updateGestureStateBasedOnDistance(

            gestureStateChangedCallback,

            distanceState,

            isFinished = { -it.deltaY >= gestureDistanceThresholdPx },

            progress = { 0f },

        )

    }

}
 
    )

packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/RecentAppsGestureMonitor.kt

+1 −1
Original line number Diff line number Diff line
@@ -26,7 +26,7 @@ import kotlin.math.abs 
 * is based on [com.android.quickstep.util.TriggerSwipeUpTouchTracker]

 */

class RecentAppsGestureMonitor(

    override val gestureDistanceThresholdPx: Int,

    private val gestureDistanceThresholdPx: Int,

    override val gestureStateChangedCallback: (GestureState) -> Unit,

    private val velocityThresholdPxPerMs: Float,

    private val velocityTracker: VelocityTracker1D = VelocityTracker1D(isDataDifferential = false),