Adding MotionValueCollection (fa32ab42) · Commits · e / os / android_frameworks_libs_systemui

mechanics/src/com/android/mechanics/MotionValue.kt

+8 −8

Original line number	Diff line number	Diff line
		@@ -129,7 +129,7 @@ class MotionValue(
		spec: () -> MotionSpec,
		label: String? = null,
		stableThreshold: Float = StableThresholdEffect,
		) : FloatState {
		) : MotionValueState {
		private val impl =
		ObservableComputations(
		inputProvider = input,
		@@ -144,7 +144,7 @@ class MotionValue(
		@get:FrequentlyChangingValue val spec: MotionSpec by impl::spec

		/** Animated [output] value. */
		@get:FrequentlyChangingValue val output: Float by impl::output
		@get:FrequentlyChangingValue override val output: Float by impl::output

		/**
		* [output] value, but without animations.
		@@ -154,14 +154,14 @@ class MotionValue(
		* While [isStable], [outputTarget] and [output] are the same value.
		*/
		// TODO(b/441041846): This should not change frequently
		@get:FrequentlyChangingValue val outputTarget: Float by impl::outputTarget
		@get:FrequentlyChangingValue override val outputTarget: Float by impl::outputTarget

		/** The [output] exposed as [FloatState]. */
		@get:FrequentlyChangingValue override val floatValue: Float by impl::output

		/** Whether an animation is currently running. */
		// TODO(b/441041846): This should not change frequently
		@get:FrequentlyChangingValue val isStable: Boolean by impl::isStable
		@get:FrequentlyChangingValue override val isStable: Boolean by impl::isStable

		/**
		* Whether the output can change its value.
		@@ -181,14 +181,14 @@ class MotionValue(
		*/
		// TODO(b/441041846): This should not change frequently
		@FrequentlyChangingValue
		operator fun <T> get(key: SemanticKey<T>): T? {
		override operator fun <T> get(key: SemanticKey<T>): T? {
		return impl.semanticState(key)
		}

		/** The current segment used to compute the output. */
		// TODO(b/441041846): This should not change frequently
		@get:FrequentlyChangingValue
		val segmentKey: SegmentKey
		override val segmentKey: SegmentKey
		get() = impl.currentComputedValues.segment.key

		/**
		@@ -223,7 +223,7 @@ class MotionValue(
		impl.keepRunning { continueRunning.invoke(this@MotionValue) }
		}

		val label: String? by impl::label
		override val label: String? by impl::label

		companion object {
		/** Creates a [MotionValue] whose [currentInput] is the animated [output] of [source]. */
		@@ -261,7 +261,7 @@ class MotionValue(
		*
		* The returned [DebugInspector] must be [DebugInspector.dispose]d when no longer needed.
		*/
		fun debugInspector(): DebugInspector {
		override fun debugInspector(): DebugInspector {
		if (debugInspectorRefCount.getAndIncrement() == 0) {
		impl.debugInspector =
		DebugInspector(

mechanics/src/com/android/mechanics/MotionValueCollection.kt

0 → 100644

+449 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2025 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.mechanics

		import androidx.annotation.VisibleForTesting
		import androidx.compose.runtime.getValue
		import androidx.compose.runtime.mutableFloatStateOf
		import androidx.compose.runtime.mutableLongStateOf
		import androidx.compose.runtime.mutableStateOf
		import androidx.compose.runtime.mutableStateSetOf
		import androidx.compose.runtime.referentialEqualityPolicy
		import androidx.compose.runtime.setValue
		import androidx.compose.runtime.snapshotFlow
		import androidx.compose.runtime.withFrameNanos
		import com.android.mechanics.MotionValue.Companion.StableThresholdSpatial
		import com.android.mechanics.debug.DebugInspector
		import com.android.mechanics.debug.FrameData
		import com.android.mechanics.impl.Computations
		import com.android.mechanics.impl.DiscontinuityAnimation
		import com.android.mechanics.impl.GuaranteeState
		import com.android.mechanics.spec.InputDirection
		import com.android.mechanics.spec.MotionSpec
		import com.android.mechanics.spec.SegmentData
		import com.android.mechanics.spec.SegmentKey
		import com.android.mechanics.spec.SemanticKey
		import com.android.mechanics.spring.SpringState
		import java.util.concurrent.atomic.AtomicInteger
		import kotlinx.coroutines.CoroutineName
		import kotlinx.coroutines.DisposableHandle
		import kotlinx.coroutines.flow.first
		import kotlinx.coroutines.withContext

		/** The type of MotionValue created by the [MotionValueCollection]. */
		sealed interface ManagedMotionValue : MotionValueState, DisposableHandle

		/**
		* A collection of motion values that all share the same input and gesture context.
		*
		* All [ManagedMotionValue]s are run from the same [keepRunning], and share the same lifecycle.
		*/
		class MotionValueCollection(
		internal val input: () -> Float,
		internal val gestureContext: GestureContext,
		internal val stableThreshold: Float = StableThresholdSpatial,
		val label: String? = null,
		) {
		private val managedComputations = mutableStateSetOf<ManagedMotionComputation>()

		/**
		* Creates a new [ManagedMotionValue], whose output is controlled by [spec].
		*
		* The returned [ManagedMotionValue] must be disposed when not used anymore, while this
		* [MotionValueCollection] is kept active.
		*/
		fun create(spec: () -> MotionSpec, label: String? = null): ManagedMotionValue {
		return ManagedMotionComputation(this, spec, label).also { managedComputations.add(it) }
		}

		/**
		* Keeps the all created [ManagedMotionValue]'s animated output running.
		*
		* Clients must call [keepRunning], and keep the coroutine running while any of the created
		* [ManagedMotionValue] is in use. Cancel the coroutine if no values are being used anymore.
		*
		* Internally, this method does suspend, unless there are animations ongoing.
		*/
		suspend fun keepRunning(): Nothing {
		withContext(CoroutineName("MotionValueCollection($label)")) {
		check(!isActive) { "MotionValueCollection($label) is already running" }
		isActive = true

		// These `captured` values will be applied to the `last` values, at the beginning
		// of the each new frame.
		// TODO(b/397837971): Encapsulate the state in a StateRecord.
		var capturedFrameTimeNanos = currentAnimationTimeNanos
		var capturedInput = currentInput
		var capturedGestureDragOffset = currentGestureDragOffset
		var capturedDirection = currentDirection

		val activeComputations = mutableSetOf<ManagedMotionComputation>()
		managedComputations.forEach {
		it.onActivate()
		activeComputations.add(it)
		}
		activeComputationCount = activeComputations.size

		try {
		isAnimating = true

		// indicates whether withFrameNanos is called continuously (as opposed to being
		// suspended for an undetermined amount of time in between withFrameNanos).
		// This is essential after `withFrameNanos` returned: if true at this point,
		// currentAnimationTimeNanos - lastFrameNanos is the duration of the last frame.
		var isAnimatingUninterrupted = false

		while (true) {

		withFrameNanos { frameTimeNanos ->
		val addedComputations = managedComputations - activeComputations
		val removedComputations = activeComputations - managedComputations
		addedComputations.forEach {
		it.onActivate()
		activeComputations.add(it)
		}
		removedComputations.forEach {
		it.onDeactivate()
		activeComputations.remove(it)
		}
		activeComputationCount = activeComputations.size
		frameCount++

		currentAnimationTimeNanos = frameTimeNanos
		lastFrameTimeNanos = capturedFrameTimeNanos
		lastInput = capturedInput
		lastGestureDragOffset = capturedGestureDragOffset

		// TODO - capture input

		activeComputations.forEach { it.onFrameStart() }
		}

		// At this point, the complete frame is done (including layout, drawing and
		// everything else), and this MotionValue has been updated.

		// Capture the `current*` MotionValue state, so that it can be applied as the
		// `last*` state when the next frame starts. Its imperative to capture at this
		// point
		// already (since the input could change before the next frame starts), while at
		// the
		// same time not already applying the `last*` state (as this would cause a
		// re-computation if the current state is being read before the next frame).

		var scheduleNextFrame = false
		activeComputations.forEach {
		if (it.onFrameEnd(isAnimatingUninterrupted)) {
		scheduleNextFrame = true
		}
		}

		if (capturedInput != currentInput) {
		capturedInput = currentInput
		scheduleNextFrame = true
		}

		if (capturedGestureDragOffset != currentGestureDragOffset) {
		capturedGestureDragOffset = currentGestureDragOffset
		scheduleNextFrame = true
		}

		if (capturedDirection != currentDirection) {
		capturedDirection = currentDirection
		scheduleNextFrame = true
		}

		capturedFrameTimeNanos = currentAnimationTimeNanos

		isAnimatingUninterrupted = scheduleNextFrame
		if (scheduleNextFrame) {
		continue
		}

		isAnimating = false
		activeComputations.forEach { it.debugInspector?.isAnimating = false }
		snapshotFlow {
		val hasComputations =
		activeComputations.isNotEmpty() \|\| managedComputations.isNotEmpty()

		val wakeup =
		hasComputations &&
		(activeComputations != managedComputations \|\|
		activeComputations.any { it.wantWakeup() } \|\|
		currentInput != capturedInput \|\|
		currentDirection != capturedDirection \|\|
		currentGestureDragOffset != capturedGestureDragOffset)
		wakeup
		}
		.first { it }
		isAnimating = true
		activeComputations.forEach { it.debugInspector?.isAnimating = true }
		}
		} finally {
		isActive = false
		activeComputations.forEach { it.onDeactivate() }
		activeComputationCount = 0
		}
		}
		}

		// ---- Implementation - State shared with all ManagedMotionComputations ----------------------

		internal var currentAnimationTimeNanos by mutableLongStateOf(-1L)

		@VisibleForTesting
		val currentInput: Float
		get() = input.invoke()

		@VisibleForTesting
		val currentDirection: InputDirection
		get() = gestureContext.direction

		@VisibleForTesting
		val currentGestureDragOffset: Float
		get() = gestureContext.dragOffset

		internal var lastFrameTimeNanos by mutableLongStateOf(-1L)
		internal var lastInput by mutableFloatStateOf(currentInput)
		internal var lastGestureDragOffset by mutableFloatStateOf(currentGestureDragOffset)

		// ---- Testing related state ------------------------------------------------------------------

		@VisibleForTesting
		var isActive = false
		private set

		@VisibleForTesting
		var isAnimating = false
		private set

		@VisibleForTesting
		var frameCount = 0
		private set

		@VisibleForTesting
		var activeComputationCount = 0
		private set

		@VisibleForTesting
		// Note - this is public so that its accessible by the mechanics:testing library
		val managedMotionValues: Set<ManagedMotionValue>
		get() = managedComputations

		internal fun onDispose(toDispose: ManagedMotionComputation) {
		managedComputations.remove(toDispose)
		}
		}

		internal class ManagedMotionComputation(
		private val owner: MotionValueCollection,
		private val specProvider: () -> MotionSpec,
		override val label: String?,
		) : Computations(), ManagedMotionValue {

		override val stableThreshold: Float
		get() = owner.stableThreshold

		// ---- ManagedMotionValue --------------------------------------------------------------------

		override val spec
		get() = specProvider.invoke()

		override fun <T> get(key: SemanticKey<T>): T? = semanticState(key)

		override val segmentKey: SegmentKey
		get() = currentComputedValues.segment.key

		override val floatValue: Float
		get() = output

		override fun dispose() {
		owner.onDispose(this)
		}

		override fun debugInspector(): DebugInspector {
		if (debugInspectorRefCount.getAndIncrement() == 0) {
		debugInspector =
		DebugInspector(
		FrameData(
		lastInput,
		lastSegment.direction,
		lastGestureDragOffset,
		lastFrameTimeNanos,
		lastSpringState,
		lastSegment,
		lastAnimation,
		isOutputFixed,
		),
		owner.isActive,
		owner.isAnimating,
		::onDisposeDebugInspector,
		)
		}

		return checkNotNull(debugInspector)
		}

		private var debugInspectorRefCount = AtomicInteger(0)

		private fun onDisposeDebugInspector() {
		if (debugInspectorRefCount.decrementAndGet() == 0) {
		debugInspector = null
		}
		}

		// ---- CurrentFrameInput ---------------------------------------------------------------------

		override val currentInput: Float
		get() = owner.currentInput

		override val currentDirection: InputDirection
		get() = owner.currentDirection

		override val currentGestureDragOffset: Float
		get() = owner.currentGestureDragOffset

		override val currentAnimationTimeNanos
		get() = owner.currentAnimationTimeNanos

		// ---- LastFrameState ---------------------------------------------------------------------

		override var lastSegment: SegmentData by
		mutableStateOf(
		this.spec.segmentAtInput(currentInput, currentDirection),
		referentialEqualityPolicy(),
		)

		override var lastGuaranteeState: GuaranteeState
		get() = GuaranteeState(_lastGuaranteeStatePacked)
		set(value) {
		_lastGuaranteeStatePacked = value.packedValue
		}

		private var _lastGuaranteeStatePacked: Long by
		mutableLongStateOf(GuaranteeState.Inactive.packedValue)

		override var lastAnimation: DiscontinuityAnimation by
		mutableStateOf(DiscontinuityAnimation.None, referentialEqualityPolicy())

		override var directMappedVelocity: Float = 0f

		override var lastSpringState: SpringState
		get() = SpringState(_lastSpringStatePacked)
		set(value) {
		_lastSpringStatePacked = value.packedValue
		}

		private var _lastSpringStatePacked: Long by
		mutableLongStateOf(lastAnimation.springStartState.packedValue)

		override val lastFrameTimeNanos
		get() = owner.lastFrameTimeNanos

		override val lastInput
		get() = owner.lastInput

		override val lastGestureDragOffset
		get() = owner.lastGestureDragOffset

		// ---- Computations ---------------------------------------------------------------------------

		var debugInspector: DebugInspector? = null

		// These `captured` values will be applied to the `last` values, at the beginning
		// of the each new frame.
		// TODO(b/397837971): Encapsulate the state in a StateRecord.
		var capturedSegment = currentComputedValues.segment
		var capturedGuaranteeState = currentComputedValues.guarantee
		var capturedAnimation = currentComputedValues.animation
		var capturedSpringState = currentSpringState

		fun onActivate() {
		val currentComputedValues = currentComputedValues
		capturedSegment = currentComputedValues.segment
		capturedGuaranteeState = currentComputedValues.guarantee
		capturedAnimation = currentComputedValues.animation
		capturedSpringState = currentSpringState

		debugInspector?.isAnimating = true
		debugInspector?.isActive = true
		}

		fun onDeactivate() {
		debugInspector?.isAnimating = false
		debugInspector?.isActive = false
		}

		fun onFrameStart() {
		lastSegment = capturedSegment
		lastGuaranteeState = capturedGuaranteeState
		lastAnimation = capturedAnimation
		lastSpringState = capturedSpringState
		}

		fun onFrameEnd(isAnimatingUninterrupted: Boolean): Boolean {
		directMappedVelocity =
		if (isAnimatingUninterrupted) {
		computeDirectMappedVelocity(currentAnimationTimeNanos - lastFrameTimeNanos)
		} else 0f

		var scheduleNextFrame = false
		if (!isSameSegmentAndAtRest) {
		// Read currentComputedValues only once and update it, if necessary
		val currentValues = currentComputedValues

		if (capturedSegment != currentValues.segment) {
		capturedSegment = currentValues.segment
		scheduleNextFrame = true
		}

		if (capturedGuaranteeState != currentValues.guarantee) {
		capturedGuaranteeState = currentValues.guarantee
		scheduleNextFrame = true
		}

		if (capturedAnimation != currentValues.animation) {
		capturedAnimation = currentValues.animation
		scheduleNextFrame = true
		}

		if (capturedSpringState != currentSpringState) {
		capturedSpringState = currentSpringState
		scheduleNextFrame = true
		}
		}

		debugInspector?.run {
		frame =
		FrameData(
		currentInput,
		currentDirection,
		currentGestureDragOffset,
		currentAnimationTimeNanos,
		capturedSpringState,
		capturedSegment,
		capturedAnimation,
		isOutputFixed,
		)
		}

		return scheduleNextFrame
		}

		fun wantWakeup(): Boolean {
		return spec != capturedSegment.spec
		}
		}

mechanics/src/com/android/mechanics/MotionValueState.kt

0 → 100644

+63 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2025 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.mechanics

		import androidx.compose.runtime.FloatState
		import androidx.compose.runtime.Stable
		import com.android.mechanics.debug.DebugInspector
		import com.android.mechanics.spec.SegmentKey
		import com.android.mechanics.spec.SemanticKey

		/** State produces by a motion value. */
		@Stable
		sealed interface MotionValueState : FloatState {

		/**
		* Animated [output] value.
		*
		* Same as [floatValue].
		*/
		val output: Float

		/**
		* [output] value, but without animations.
		*
		* This value always reports the target value, even before a animation is finished.
		*
		* While [isStable], [outputTarget] and [output] are the same value.
		*/
		val outputTarget: Float

		/** Whether an animation is currently running. */
		val isStable: Boolean

		/**
		* The current value for the [SemanticKey].
		*
		* `null` if not defined in the spec.
		*/
		operator fun <T> get(key: SemanticKey<T>): T?

		/** The current segment used to compute the output. */
		val segmentKey: SegmentKey

		/** Debug label of the motion value. */
		val label: String?

		/** Provides access to the current state for debugging.. */
		fun debugInspector(): DebugInspector
		}

mechanics/testing/src/com/android/mechanics/testing/ComposeMotionValueCollectionToolkit.kt

0 → 100644

+210 −0

File added.

Preview size limit exceeded, changes collapsed.

mechanics/testing/src/com/android/mechanics/testing/ComposeMotionValueToolkit.kt

+8 −1

Original line number	Diff line number	Diff line
		@@ -26,6 +26,7 @@ import com.android.mechanics.DistanceGestureContext
		import com.android.mechanics.MotionValue
		import com.android.mechanics.spec.InputDirection
		import com.android.mechanics.spec.MotionSpec
		import com.android.mechanics.testing.MotionValueToolkit.Companion.FrameDuration
		import kotlinx.coroutines.Dispatchers
		import kotlinx.coroutines.ExperimentalCoroutinesApi
		import kotlinx.coroutines.flow.MutableStateFlow
		@@ -43,7 +44,13 @@ import platform.test.motion.golden.TimeSeries
		import platform.test.motion.golden.TimestampFrameId

		/** Toolkit to support [MotionValue] motion tests. */
		data object ComposeMotionValueToolkit : MotionValueToolkit<MotionValue, DistanceGestureContext>() {
		data object ComposeMotionValueToolkit :
		MotionValueToolkit<
		InputScope<MotionValue, DistanceGestureContext>,
		MotionValue,
		MotionValue,
		DistanceGestureContext,
		>() {

		override fun goldenTest(
		motionTestRule: MotionTestRule<*>,