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

Commit 07a66114 authored by Omar Miatello's avatar Omar Miatello
Browse files

MM: fast path to calculate output/target in MotionValues when stable 

When a MotionValue is stable (i.e., there's no animation happening), we
can calculate the output and the targetOutput directly from the previous
mapping or animation.

The fast path enabled performance gains of up to 20x in some of our
tests.

Test: MotionValueBenchmark (run on AS, results go/mm-microbenchmarks)
Test: atest MotionValueTest
Bug: 404975090
Flag: com.android.systemui.scene_container
Change-Id: I041ddb8411832e746924b7c6ada0771d02656de9
parent 8c5e4b54

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

+18 −16
Original line number Diff line number Diff line
@@ -376,7 +376,8 @@ private class ObservableComputations( 
                    directMappedVelocity = 0f

                }



                var scheduleNextFrame = !isStable

                var scheduleNextFrame = false

                if (!isSameSegmentAndAtRest) {

                    if (capturedSegment != currentSegment) {

                        capturedSegment = currentSegment

                        scheduleNextFrame = true
@@ -396,6 +397,7 @@ private class ObservableComputations( 
                        capturedSpringState = currentSpringState

                        scheduleNextFrame = true

                    }

                }



                if (capturedInput != currentInput) {

                    capturedInput = currentInput

mechanics/src/com/android/mechanics/impl/Computations.kt

+39 −6
Original line number Diff line number Diff line
@@ -423,22 +423,55 @@ internal interface ComputeSpringState : ComputeAnimation { 
internal interface Computations : ComputeSpringState {

    val currentSpringState: SpringState



    val isSameSegmentAndAtRest: Boolean

        get() =

            lastAnimation.isAtRest &&

                lastSegment.spec == spec &&

                lastSegment.isValidForInput(currentInput, currentDirection)



    val currentDirectMapped: Float

        get() = currentSegment.mapping.map(currentInput) - currentAnimation.targetValue

        get() =

            if (isSameSegmentAndAtRest) {

                lastSegment.mapping.map(currentInput)

            } else {

                currentSegment.mapping.map(currentInput) - currentAnimation.targetValue

            }



    val currentAnimatedDelta: Float

        get() = currentAnimation.targetValue + currentSpringState.displacement

        get() =

            if (isSameSegmentAndAtRest) {

                0f

            } else {

                currentAnimation.targetValue + currentSpringState.displacement

            }



    val output: Float

        get() = currentDirectMapped + currentAnimatedDelta

        get() =

            if (isSameSegmentAndAtRest) {

                lastSegment.mapping.map(currentInput)

            } else {

                currentDirectMapped + currentAnimatedDelta

            }



    val outputTarget: Float

        get() = currentDirectMapped + currentAnimation.targetValue

        get() =

            if (isSameSegmentAndAtRest) {

                lastAnimation.targetValue

            } else {

                currentDirectMapped + currentAnimation.targetValue

            }



    val isStable: Boolean

        get() = currentSpringState == SpringState.AtRest

        get() =

            if (isSameSegmentAndAtRest) {

                true

            } else {

                currentSpringState == SpringState.AtRest

            }



    fun <T> semanticState(semanticKey: SemanticKey<T>): T? {

        return with(currentSegment) { spec.semanticState(semanticKey, key) }

        return with(if (isSameSegmentAndAtRest) lastSegment else currentSegment) {

            spec.semanticState(semanticKey, key)

        }

    }

}

mechanics/src/com/android/mechanics/view/ViewMotionValue.kt

+6 −4
Original line number Diff line number Diff line
@@ -277,10 +277,12 @@ private class ImperativeComputations( 


        currentAnimationTimeNanos = frameTimeMillis * 1_000_000L



        if (!isSameSegmentAndAtRest) {

            currentSegment = computeCurrentSegment()

            currentGuaranteeState = computeCurrentGuaranteeState()

            currentAnimation = computeCurrentAnimation()

            currentSpringState = computeCurrentSpringState()

        }



        debugInspector?.run {

            frame =