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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#ifndef mozilla_layers_AnimationHelper_h
#define mozilla_layers_AnimationHelper_h
#include "mozilla/dom/Nullable.h"
#include "mozilla/layers/AnimationStorageData.h"
#include "mozilla/layers/LayersMessages.h" // for TransformData, etc
#include "mozilla/webrender/WebRenderTypes.h" // for RenderRoot
#include "mozilla/TimeStamp.h" // for TimeStamp
#include "mozilla/TimingParams.h"
#include "mozilla/Types.h" // for SideBits
#include "X11UndefineNone.h"
#include <unordered_map>
namespace mozilla::layers {
class Animation;
class APZSampler;
class CompositorAnimationStorage;
struct AnimatedValue;
using AnimationArray = nsTArray<layers::Animation>;
using SampledAnimationArray = AutoTArray<RefPtr<StyleAnimationValue>, 1>;
/**
* This utility class allows reusing code between the webrender and
* non-webrender compositor-side implementations. It provides
* utility functions for sampling animations at particular timestamps.
*/
class AnimationHelper {
public:
struct SampleResult {
enum class Type : uint8_t { None, Skipped, Sampled };
enum class Reason : uint8_t { None, ScrollToDelayPhase };
Type mType = Type::None;
Reason mReason = Reason::None;
SampleResult() = default;
SampleResult(Type aType, Reason aReason) : mType(aType), mReason(aReason) {}
static SampleResult Skipped() { return {Type::Skipped, Reason::None}; }
static SampleResult Sampled() { return {Type::Sampled, Reason::None}; }
bool IsNone() { return mType == Type::None; }
bool IsSkipped() { return mType == Type::Skipped; }
bool IsSampled() { return mType == Type::Sampled; }
};
/**
* Sample animations based on a given time stamp for a element(layer) with
* its animation data.
* Generally |aPreviousFrameTime| is used for the sampling if it's
* supplied to make the animation more in sync with other animations on the
* main-thread. But in the case where the animation just started at the time
* when the animation was sent to the compositor, |aCurrentFrameTime| is used
* for sampling instead to avoid flicker.
*
* Returns SampleResult::None if none of the animations are producing a result
* (e.g. they are in the delay phase with no backwards fill),
* SampleResult::Skipped if the animation output did not change since the last
* call of this function,
* SampleResult::Sampled if the animation output was updated.
*
* The only exception is the scroll-driven animation. When the user move the
* scrollbar to make the animations go from active phase to delay phase, this
* returns SampleResult::None but sets its |mReason| to
* Reason::ScrollToDelayPhase. The caller can check this flag so we can store
* the base style into the hash table to make sure we have the correct
* rendering result. The base style stays in the hash table until we sync with
* main thread.
*
* Using the same example from ExtractAnimations (below):
*
* Input |aPropertyAnimationGroups| (ignoring the base animation style):
*
* [
* Group A: [ { rotate, Animation A }, { rotate, Animation B } ],
* Group B: [ { scale, Animation B } ],
* Group C: [ { transform, Animation A }, { transform, Animation B } ],
* ]
*
* For each property group, this function interpolates each animation in turn,
* using the result of interpolating one animation as input for the next such
* that it reduces each property group to a single output value:
*
* [
* { rotate, StyleAnimationValue },
* { scale, StyleAnimationValue },
* { transform, StyleAnimationValue },
* ]
*
* For transform animations, the caller (SampleAnimations) will combine the
* result of the various transform properties into a final matrix.
*/
static SampleResult SampleAnimationForEachNode(
const APZSampler* aAPZSampler, const LayersId& aLayersId,
const MutexAutoLock& aProofOfMapLock, TimeStamp aPreviousFrameTime,
TimeStamp aCurrentFrameTime, const AnimatedValue* aPreviousValue,
nsTArray<PropertyAnimationGroup>& aPropertyAnimationGroups,
SampledAnimationArray& aAnimationValues /* output */);
/**
* Extract organized animation data by property into an array of
* PropertyAnimationGroup objects.
*
* For example, suppose we have the following animations:
*
* Animation A: [ transform, rotate ]
* Animation B: [ rotate, scale ]
* Animation C: [ transform ]
* Animation D: [ opacity ]
*
* When we go to send transform-like properties to the compositor, we
* sort them as follows:
*
* [
* { rotate: Animation A (rotate segments only) },
* { rotate: Animation B ( " " ) },
* { scale: Animation B (scale segments only) },
* { transform: Animation A (transform segments only) },
* { transform: Animation C ( " " ) },
* ]
*
* In this function, we group these animations together by property producing
* output such as the following:
*
* [
* [ { rotate, Animation A }, { rotate, Animation B } ],
* [ { scale, Animation B } ],
* [ { transform, Animation A }, { transform, Animation B } ],
* ]
*
* In the process of grouping these animations, we also convert their values
* from the rather compact representation we use for transferring across the
* IPC boundary into something we can readily use for sampling.
*
* Note: the animation groups:
* 1. transform-like properties: transfrom, translate, rotate, scale,
* offset-*.
* 2. opacity property: opacity.
* 3. background color property: background-color.
*/
static AnimationStorageData ExtractAnimations(
const LayersId& aLayersId, const AnimationArray& aAnimations,
const CompositorAnimationStorage* aStorage,
const TimeStamp& aPreviousSampleTime);
/**
* Get a unique id to represent the compositor animation between child
* and parent side. This id will be used as a key to store animation
* data in the CompositorAnimationStorage per compositor.
* Each layer on the content side calls this when it gets new animation
* data.
*/
static uint64_t GetNextCompositorAnimationsId();
/**
* Convert an array of animation values into a matrix given the corresponding
* transform parameters. |aValue| must be a transform-like value
* (e.g. transform, translate etc.).
*/
static gfx::Matrix4x4 ServoAnimationValueToMatrix4x4(
const SampledAnimationArray& aValue, const TransformData& aTransformData,
gfx::Path* aCachedMotionPath);
/**
* Returns true if |aPrerenderedRect| transformed by |aTransform| were
* composited in |aClipRect| there appears area which wasn't pre-rendered
* on the main-thread. I.e. checkerboarding.
*/
static bool ShouldBeJank(const LayoutDeviceRect& aPrerenderedRect,
SideBits aOverflowedSides,
const gfx::Matrix4x4& aTransform,
const ParentLayerRect& aClipRect);
};
} // namespace mozilla::layers
#endif // mozilla_layers_AnimationHelper_h