Clean up computeValue() (2d23c9e6) · Commits · e / os / android_frameworks_base

packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/Element.kt

+195 −154

Original line number	Diff line number	Diff line
		@@ -1307,8 +1307,7 @@ private inline fun <T> computeValue(

		val currentContent = currentContentState.contents.last()

		// The element is shared: interpolate between the value in fromContent and the value in
		// toContent.
		// The element is shared: interpolate between the value in fromContent and toContent.
		// TODO(b/290184746): Support non linear shared paths as well as a way to make sure that shared
		// elements follow the finger direction.
		val isSharedElement = fromState != null && toState != null
		@@ -1343,28 +1342,133 @@ private inline fun <T> computeValue(
		// The content for which we compute the transformation. Note that this is not necessarily
		// [currentContent] because [currentContent] could be a different content than the transition
		// fromContent or toContent during interruptions or when a ancestor transition is running.
		val content: ContentKey
		val transformationContentKey: ContentKey =
		getTransformationContentKey(
		isDisabledSharedElement = isSharedElement,
		currentContent = currentContent,
		layoutImpl = layoutImpl,
		transition = transition,
		element = element,
		currentSceneState = currentSceneState,
		)
		// Get the transformed value, i.e. the target value at the beginning (for entering elements) or
		// end (for leaving elements) of the transition.
		val contentState: Element.State
		val targetState: Element.State = element.stateByContent.getValue(transformationContentKey)
		val idleValue = contentValue(targetState)

		val transformationWithRange =
		transformation(
		transition.transformationSpec.transformations(element.key, transformationContentKey)
		)

		val isElementEntering =
		when {
		isSharedElement -> {
		content = currentContent
		contentState = currentContentState
		transformationContentKey == toContent -> true
		transformationContentKey == fromContent -> false
		isAncestorTransition(layoutImpl, transition) ->
		isEnteringAncestorTransition(layoutImpl, transition)
		transformationContentKey == transition.currentScene -> toState == null
		else -> transformationContentKey == toContent
		}

		val previewTransformation =
		transition.previewTransformationSpec?.let {
		transformation(it.transformations(element.key, transformationContentKey))
		}

		if (previewTransformation != null) {
		return computePreviewTransformationValue(
		transition,
		idleValue,
		transformationContentKey,
		isElementEntering,
		previewTransformation,
		element,
		layoutImpl,
		transformationWithRange,
		lerp,
		)
		}

		if (transformationWithRange == null) {
		// If there is no transformation explicitly associated to this element value, let's use
		// the value given by the system (like the current position and size given by the layout
		// pass).
		return currentValue()
		}

		val transformation = transformationWithRange.transformation
		when (transformation) {
		is CustomPropertyTransformation ->
		return with(transformation) {
		layoutImpl.propertyTransformationScope.transform(
		transformationContentKey,
		element.key,
		transition,
		transition.coroutineScope,
		)
		}
		is InterpolatedPropertyTransformation -> {
		/* continue */
		}
		}

		val targetValue =
		with(transformation) {
		layoutImpl.propertyTransformationScope.transform(
		transformationContentKey,
		element.key,
		transition,
		idleValue,
		)
		}

		// Make sure we don't read progress if values are the same and we don't need to interpolate, so
		// we don't invalidate the phase where this is read.
		if (targetValue == idleValue) {
		return targetValue
		}

		val progress = transition.progress
		// TODO(b/290184746): Make sure that we don't overflow transformations associated to a range.
		val rangeProgress = transformationWithRange.range?.progress(progress) ?: progress

		return if (isElementEntering) {
		lerp(targetValue, idleValue, rangeProgress)
		} else {
		lerp(idleValue, targetValue, rangeProgress)
		}
		}

		private fun getTransformationContentKey(
		isDisabledSharedElement: Boolean,
		currentContent: ContentKey,
		layoutImpl: SceneTransitionLayoutImpl,
		transition: TransitionState.Transition,
		element: Element,
		currentSceneState: Element.State?,
		): ContentKey {
		return when {
		isDisabledSharedElement -> {
		currentContent
		}
		isAncestorTransition(layoutImpl, transition) -> {
		if (
		fromState != null &&
		transition.transformationSpec.hasTransformation(element.key, fromContent)
		element.stateByContent[transition.fromContent] != null &&
		transition.transformationSpec.hasTransformation(
		element.key,
		transition.fromContent,
		)
		) {
		content = fromContent
		contentState = fromState
		transition.fromContent
		} else if (
		toState != null &&
		transition.transformationSpec.hasTransformation(element.key, toContent)
		element.stateByContent[transition.toContent] != null &&
		transition.transformationSpec.hasTransformation(
		element.key,
		transition.toContent,
		)
		) {
		content = toContent
		contentState = toState
		transition.toContent
		} else {
		throw IllegalStateException(
		"Ancestor transition is active but no transformation " +
		@@ -1374,31 +1478,30 @@ private inline fun <T> computeValue(
		}
		}
		currentSceneState != null && currentContent == transition.currentScene -> {
		content = currentContent
		contentState = currentSceneState
		currentContent
		}
		fromState != null -> {
		content = fromContent
		contentState = fromState
		element.stateByContent[transition.fromContent] != null -> {
		transition.fromContent
		}
		else -> {
		content = toContent
		contentState = toState!!
		transition.toContent
		}
		}

		val transformationWithRange =
		transformation(transition.transformationSpec.transformations(element.key, content))

		val previewTransformation =
		transition.previewTransformationSpec?.let {
		transformation(it.transformations(element.key, content))
		}
		if (previewTransformation != null) {

		private inline fun <T> computePreviewTransformationValue(
		transition: TransitionState.Transition,
		idleValue: T,
		transformationContentKey: ContentKey,
		isEntering: Boolean,
		previewTransformation: TransformationWithRange<PropertyTransformation<T>>,
		element: Element,
		layoutImpl: SceneTransitionLayoutImpl,
		transformationWithRange: TransformationWithRange<PropertyTransformation<T>>?,
		lerp: (T, T, Float) -> T,
		): T {
		val isInPreviewStage = transition.isInPreviewStage

		val idleValue = contentValue(contentState)
		val isEntering = content == toContent
		val previewTargetValue =
		with(
		previewTransformation.transformation.requireInterpolatedTransformation(
		@@ -1409,7 +1512,7 @@ private inline fun <T> computeValue(
		}
		) {
		layoutImpl.propertyTransformationScope.transform(
		content,
		transformationContentKey,
		element.key,
		transition,
		idleValue,
		@@ -1427,7 +1530,7 @@ private inline fun <T> computeValue(
		}
		) {
		layoutImpl.propertyTransformationScope.transform(
		content,
		transformationContentKey,
		element.key,
		transition,
		idleValue,
		@@ -1485,74 +1588,12 @@ private inline fun <T> computeValue(
		lerp(
		lerp(idleValue, previewTargetValue, previewRangeProgress),
		targetValueOrNull,
		transformationWithRange.range?.progress(transition.progress)
		?: transition.progress,
		transformationWithRange.range?.progress(transition.progress) ?: transition.progress,
		)
		}
		}
		}

		if (transformationWithRange == null) {
		// If there is no transformation explicitly associated to this element value, let's use
		// the value given by the system (like the current position and size given by the layout
		// pass).
		return currentValue()
		}

		val transformation = transformationWithRange.transformation
		when (transformation) {
		is CustomPropertyTransformation ->
		return with(transformation) {
		layoutImpl.propertyTransformationScope.transform(
		content,
		element.key,
		transition,
		transition.coroutineScope,
		)
		}
		is InterpolatedPropertyTransformation -> {
		/* continue */
		}
		}

		val idleValue = contentValue(contentState)
		val targetValue =
		with(transformation) {
		layoutImpl.propertyTransformationScope.transform(
		content,
		element.key,
		transition,
		idleValue,
		)
		}

		// Make sure we don't read progress if values are the same and we don't need to interpolate, so
		// we don't invalidate the phase where this is read.
		if (targetValue == idleValue) {
		return targetValue
		}

		val progress = transition.progress
		// TODO(b/290184746): Make sure that we don't overflow transformations associated to a range.
		val rangeProgress = transformationWithRange.range?.progress(progress) ?: progress

		// Interpolate between the value at rest and the value before entering/after leaving.
		val isEntering =
		when {
		content == toContent -> true
		content == fromContent -> false
		isAncestorTransition(layoutImpl, transition) ->
		isEnteringAncestorTransition(layoutImpl, transition)
		content == transition.currentScene -> toState == null
		else -> content == toContent
		}
		return if (isEntering) {
		lerp(targetValue, idleValue, rangeProgress)
		} else {
		lerp(idleValue, targetValue, rangeProgress)
		}
		}

		private fun isAncestorTransition(
		layoutImpl: SceneTransitionLayoutImpl,
		transition: TransitionState.Transition,
		@@ -1564,7 +1605,7 @@ private fun isAncestorTransition(

		private fun isEnteringAncestorTransition(
		layoutImpl: SceneTransitionLayoutImpl,
		transition: TransitionState.Transition
		transition: TransitionState.Transition,
		): Boolean {
		return layoutImpl.ancestors.fastAny { it.inContent == transition.toContent }
		}