/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set sw=2 ts=8 et 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include <math.h> // for fabsf, fabs, atan2
#include <stdint.h> // for uint32_t, uint64_t
#include <sys/types.h> // for int32_t
#include <algorithm> // for max, min
#include "AsyncPanZoomController.h" // for AsyncPanZoomController, etc
#include "Axis.h" // for AxisX, AxisY, Axis, etc
#include "CheckerboardEvent.h" // for CheckerboardEvent
#include "Compositor.h" // for Compositor
#include "FrameMetrics.h" // for FrameMetrics, etc
#include "GenericFlingAnimation.h" // for GenericFlingAnimation
#include "GestureEventListener.h" // for GestureEventListener
#include "HitTestingTreeNode.h" // for HitTestingTreeNode
#include "InputData.h" // for MultiTouchInput, etc
#include "InputBlockState.h" // for InputBlockState, TouchBlockState
#include "InputQueue.h" // for InputQueue
#include "Overscroll.h" // for OverscrollAnimation
#include "OverscrollHandoffState.h" // for OverscrollHandoffState
#include "Units.h" // for CSSRect, CSSPoint, etc
#include "UnitTransforms.h" // for TransformTo
#include "base/message_loop.h" // for MessageLoop
#include "base/task.h" // for NewRunnableMethod, etc
#include "gfxPrefs.h" // for gfxPrefs
#include "gfxTypes.h" // for gfxFloat
#include "LayersLogging.h" // for print_stderr
#include "mozilla/Assertions.h" // for MOZ_ASSERT, etc
#include "mozilla/BasicEvents.h" // for Modifiers, MODIFIER_*
#include "mozilla/ClearOnShutdown.h" // for ClearOnShutdown
#include "mozilla/ComputedTimingFunction.h" // for ComputedTimingFunction
#include "mozilla/EventForwards.h" // for nsEventStatus_*
#include "mozilla/MouseEvents.h" // for WidgetWheelEvent
#include "mozilla/Preferences.h" // for Preferences
#include "mozilla/ReentrantMonitor.h" // for ReentrantMonitorAutoEnter, etc
#include "mozilla/RefPtr.h" // for RefPtr
#include "mozilla/StaticPtr.h" // for StaticAutoPtr
#include "mozilla/TimeStamp.h" // for TimeDuration, TimeStamp
#include "mozilla/dom/CheckerboardReportService.h" // for CheckerboardEventStorage
// note: CheckerboardReportService.h actually lives in gfx/layers/apz/util/
#include "mozilla/dom/Touch.h" // for Touch
#include "mozilla/gfx/BasePoint.h" // for BasePoint
#include "mozilla/gfx/BaseRect.h" // for BaseRect
#include "mozilla/gfx/Point.h" // for Point, RoundedToInt, etc
#include "mozilla/gfx/Rect.h" // for RoundedIn
#include "mozilla/gfx/ScaleFactor.h" // for ScaleFactor
#include "mozilla/layers/APZCTreeManager.h" // for ScrollableLayerGuid
#include "mozilla/layers/APZThreadUtils.h" // for AssertOnControllerThread, etc
#include "mozilla/layers/AsyncCompositionManager.h" // for ViewTransform
#include "mozilla/layers/AxisPhysicsModel.h" // for AxisPhysicsModel
#include "mozilla/layers/AxisPhysicsMSDModel.h" // for AxisPhysicsMSDModel
#include "mozilla/layers/CompositorController.h" // for CompositorController
#include "mozilla/layers/LayerTransactionParent.h" // for LayerTransactionParent
#include "mozilla/layers/MetricsSharingController.h" // for MetricsSharingController
#include "mozilla/layers/ScrollInputMethods.h" // for ScrollInputMethod
#include "mozilla/mozalloc.h" // for operator new, etc
#include "mozilla/Unused.h" // for unused
#include "mozilla/FloatingPoint.h" // for FuzzyEquals*
#include "nsAlgorithm.h" // for clamped
#include "nsCOMPtr.h" // for already_AddRefed
#include "nsDebug.h" // for NS_WARNING
#include "nsIDOMWindowUtils.h" // for nsIDOMWindowUtils
#include "nsMathUtils.h" // for NS_hypot
#include "nsPoint.h" // for nsIntPoint
#include "nsStyleConsts.h"
#include "nsStyleStruct.h" // for nsTimingFunction
#include "nsTArray.h" // for nsTArray, nsTArray_Impl, etc
#include "nsThreadUtils.h" // for NS_IsMainThread
#include "nsViewportInfo.h" // for kViewportMinScale, kViewportMaxScale
#include "prsystem.h" // for PR_GetPhysicalMemorySize
#include "SharedMemoryBasic.h" // for SharedMemoryBasic
#include "ScrollSnap.h" // for ScrollSnapUtils
#include "WheelScrollAnimation.h"
#if defined(MOZ_WIDGET_ANDROID)
#include "AndroidAPZ.h"
#endif // defined(MOZ_WIDGET_ANDROID)
#define ENABLE_APZC_LOGGING 0
// #define ENABLE_APZC_LOGGING 1
#if ENABLE_APZC_LOGGING
# define APZC_LOG(...) printf_stderr("APZC: " __VA_ARGS__)
# define APZC_LOG_FM(fm, prefix, ...) \
{ std::stringstream ss; \
ss << nsPrintfCString(prefix, __VA_ARGS__).get(); \
AppendToString(ss, fm, ":", "", true); \
APZC_LOG("%s\n", ss.str().c_str()); \
}
#else
# define APZC_LOG(...)
# define APZC_LOG_FM(fm, prefix, ...)
#endif
namespace mozilla {
namespace layers {
typedef mozilla::layers::AllowedTouchBehavior AllowedTouchBehavior;
typedef GeckoContentController::APZStateChange APZStateChange;
typedef GeckoContentController::TapType TapType;
typedef mozilla::gfx::Point Point;
typedef mozilla::gfx::Matrix4x4 Matrix4x4;
using mozilla::gfx::PointTyped;
// Choose between platform-specific implementations.
#ifdef MOZ_WIDGET_ANDROID
typedef WidgetOverscrollEffect OverscrollEffect;
typedef AndroidSpecificState PlatformSpecificState;
typedef AndroidFlingAnimation FlingAnimation;
#else
typedef GenericOverscrollEffect OverscrollEffect;
typedef PlatformSpecificStateBase PlatformSpecificState; // no extra state, just use the base class
typedef GenericFlingAnimation FlingAnimation;
#endif
/**
* \page APZCPrefs APZ preferences
*
* The following prefs are used to control the behaviour of the APZC.
* The default values are provided in gfxPrefs.h.
*
* \li\b apz.allow_checkerboarding
* Pref that allows or disallows checkerboarding
*
* \li\b apz.allow_immediate_handoff
* If set to true, scroll can be handed off from one APZC to another within
* a single input block. If set to false, a single input block can only
* scroll one APZC.
*
* \li\b apz.axis_lock.mode
* The preferred axis locking style. See AxisLockMode for possible values.
*
* \li\b apz.axis_lock.lock_angle
* Angle from axis within which we stay axis-locked.\n
* Units: radians
*
* \li\b apz.axis_lock.breakout_threshold
* Distance in inches the user must pan before axis lock can be broken.\n
* Units: (real-world, i.e. screen) inches
*
* \li\b apz.axis_lock.breakout_angle
* Angle at which axis lock can be broken.\n
* Units: radians
*
* \li\b apz.axis_lock.direct_pan_angle
* If the angle from an axis to the line drawn by a pan move is less than
* this value, we can assume that panning can be done in the allowed direction
* (horizontal or vertical).\n
* Currently used only for touch-action css property stuff and was addded to
* keep behaviour consistent with IE.\n
* Units: radians
*
* \li\b apz.content_response_timeout
* Amount of time before we timeout response from content. For example, if
* content is being unruly/slow and we don't get a response back within this
* time, we will just pretend that content did not preventDefault any touch
* events we dispatched to it.\n
* Units: milliseconds
*
* \li\b apz.danger_zone_x
* \li\b apz.danger_zone_y
* When drawing high-res tiles, we drop down to drawing low-res tiles
* when we know we can't keep up with the scrolling. The way we determine
* this is by checking if we are entering the "danger zone", which is the
* boundary of the painted content. For example, if the painted content
* goes from y=0...1000 and the visible portion is y=250...750 then
* we're far from checkerboarding. If we get to y=490...990 though then we're
* only 10 pixels away from showing checkerboarding so we are probably in
* a state where we can't keep up with scrolling. The danger zone prefs specify
* how wide this margin is; in the above example a y-axis danger zone of 10
* pixels would make us drop to low-res at y=490...990.\n
* This value is in layer pixels.
*
* \li\b apz.disable_for_scroll_linked_effects
* Setting this pref to true will disable APZ scrolling on documents where
* scroll-linked effects are detected. A scroll linked effect is detected if
* positioning or transform properties are updated inside a scroll event
* dispatch; we assume that such an update is in response to the scroll event
* and is therefore a scroll-linked effect which will be laggy with APZ
* scrolling.
*
* \li\b apz.displayport_expiry_ms
* While a scrollable frame is scrolling async, we set a displayport on it
* to make sure it is layerized. However this takes up memory, so once the
* scrolling stops we want to remove the displayport. This pref controls how
* long after scrolling stops the displayport is removed. A value of 0 will
* disable the expiry behavior entirely.
* Units: milliseconds
*
* \li\b apz.enlarge_displayport_when_clipped
* Pref that enables enlarging of the displayport along one axis when the
* generated displayport's size is beyond that of the scrollable rect on the
* opposite axis.
*
* \li\b apz.fling_accel_interval_ms
* The time that determines whether a second fling will be treated as
* accelerated. If two flings are started within this interval, the second one
* will be accelerated. Setting an interval of 0 means that acceleration will
* be disabled.\n
* Units: milliseconds
*
* \li\b apz.fling_accel_min_velocity
* The minimum velocity of the second fling for it to be considered for fling
* acceleration.
* Units: screen pixels per milliseconds
*
* \li\b apz.fling_accel_base_mult
* \li\b apz.fling_accel_supplemental_mult
* When applying an acceleration on a fling, the new computed velocity is
* (new_fling_velocity * base_mult) + (old_velocity * supplemental_mult).
* The base_mult and supplemental_mult multiplier values are controlled by
* these prefs. Note that "old_velocity" here is the initial velocity of the
* previous fling _after_ acceleration was applied to it (if applicable).
*
* \li\b apz.fling_curve_function_x1
* \li\b apz.fling_curve_function_y1
* \li\b apz.fling_curve_function_x2
* \li\b apz.fling_curve_function_y2
* \li\b apz.fling_curve_threshold_inches_per_ms
* These five parameters define a Bezier curve function and threshold used to
* increase the actual velocity relative to the user's finger velocity. When the
* finger velocity is below the threshold (or if the threshold is not positive),
* the velocity is used as-is. If the finger velocity exceeds the threshold
* velocity, then the function defined by the curve is applied on the part of
* the velocity that exceeds the threshold. Note that the upper bound of the
* velocity is still specified by the \b apz.max_velocity_inches_per_ms pref, and
* the function will smoothly curve the velocity from the threshold to the
* max. In general the function parameters chosen should define an ease-out
* curve in order to increase the velocity in this range, or an ease-in curve to
* decrease the velocity. A straight-line curve is equivalent to disabling the
* curve entirely by setting the threshold to -1. The max velocity pref must
* also be set in order for the curving to take effect, as it defines the upper
* bound of the velocity curve.\n
* The points (x1, y1) and (x2, y2) used as the two intermediate control points
* in the cubic bezier curve; the first and last points are (0,0) and (1,1).\n
* Some example values for these prefs can be found at\n
* https://dxr.mozilla.org/mozilla-central/rev/70e05c6832e831374604ac3ce7433971368dffe0/layout/style/nsStyleStruct.cpp#2729
*
* \li\b apz.fling_friction
* Amount of friction applied during flings. This is used in the following
* formula: v(t1) = v(t0) * (1 - f)^(t1 - t0), where v(t1) is the velocity
* for a new sample, v(t0) is the velocity at the previous sample, f is the
* value of this pref, and (t1 - t0) is the amount of time, in milliseconds,
* that has elapsed between the two samples.\n
* NOTE: Not currently used in Android fling calculations.
*
* \li\b apz.fling_min_velocity_threshold
* Minimum velocity for a fling to actually kick off. If the user pans and lifts
* their finger such that the velocity is smaller than this amount, no fling
* is initiated.\n
* Units: screen pixels per millisecond
*
* \li\b apz.fling_stop_on_tap_threshold
* When flinging, if the velocity is above this number, then a tap on the
* screen will stop the fling without dispatching a tap to content. If the
* velocity is below this threshold a tap will also be dispatched.
* Note: when modifying this pref be sure to run the APZC gtests as some of
* them depend on the value of this pref.\n
* Units: screen pixels per millisecond
*
* \li\b apz.fling_stopped_threshold
* When flinging, if the velocity goes below this number, we just stop the
* animation completely. This is to prevent asymptotically approaching 0
* velocity and rerendering unnecessarily.\n
* Units: screen pixels per millisecond.\n
* NOTE: Should not be set to anything
* other than 0.0 for Android except for tests to disable flings.
*
* \li\b apz.max_velocity_inches_per_ms
* Maximum velocity. Velocity will be capped at this value if a faster fling
* occurs. Negative values indicate unlimited velocity.\n
* Units: (real-world, i.e. screen) inches per millisecond
*
* \li\b apz.max_velocity_queue_size
* Maximum size of velocity queue. The queue contains last N velocity records.
* On touch end we calculate the average velocity in order to compensate
* touch/mouse drivers misbehaviour.
*
* \li\b apz.min_skate_speed
* Minimum amount of speed along an axis before we switch to "skate" multipliers
* rather than using the "stationary" multipliers.\n
* Units: CSS pixels per millisecond
*
* \li\b apz.overscroll.enabled
* Pref that enables overscrolling. If this is disabled, excess scroll that
* cannot be handed off is discarded.
*
* \li\b apz.overscroll.min_pan_distance_ratio
* The minimum ratio of the pan distance along one axis to the pan distance
* along the other axis needed to initiate overscroll along the first axis
* during panning.
*
* \li\b apz.overscroll.stretch_factor
* How much overscrolling can stretch content along an axis.
* The maximum stretch along an axis is a factor of (1 + kStretchFactor).
* (So if kStretchFactor is 0, you can't stretch at all; if kStretchFactor
* is 1, you can stretch at most by a factor of 2).
*
* \li\b apz.overscroll.spring_stiffness
* The stiffness of the spring used in the physics model for the overscroll
* animation.
*
* \li\b apz.overscroll.spring_friction
* The friction of the spring used in the physics model for the overscroll
* animation.
* Even though a realistic physics model would dictate that this be the same
* as \b apz.fling_friction, we allow it to be set to be something different,
* because in practice we want flings to skate smoothly (low friction), while
* we want the overscroll bounce-back to oscillate few times (high friction).
*
* \li\b apz.overscroll.stop_distance_threshold
* \li\b apz.overscroll.stop_velocity_threshold
* Thresholds for stopping the overscroll animation. When both the distance
* and the velocity fall below their thresholds, we stop oscillating.\n
* Units: screen pixels (for distance)
* screen pixels per millisecond (for velocity)
*
* \li\b apz.paint_skipping.enabled
* When APZ is scrolling and sending repaint requests to the main thread, often
* the main thread doesn't actually need to do a repaint. This pref allows the
* main thread to skip doing those repaints in cases where it doesn't need to.
*
* \li\b apz.record_checkerboarding
* Whether or not to record detailed info on checkerboarding events.
*
* \li\b apz.test.logging_enabled
* Enable logging of APZ test data (see bug 961289).
*
* \li\b apz.touch_move_tolerance
* See the description for apz.touch_start_tolerance below. This is a similar
* threshold, except it is used to suppress touchmove events from being delivered
* to content for NON-scrollable frames (or more precisely, for APZCs where
* ArePointerEventsConsumable returns false).\n
* Units: (real-world, i.e. screen) inches
*
* \li\b apz.touch_start_tolerance
* Constant describing the tolerance in distance we use, multiplied by the
* device DPI, before we start panning the screen. This is to prevent us from
* accidentally processing taps as touch moves, and from very short/accidental
* touches moving the screen. touchmove events are also not delivered to content
* within this distance on scrollable frames.\n
* Units: (real-world, i.e. screen) inches
*
* \li\b apz.velocity_bias
* How much to adjust the displayport in the direction of scrolling. This value
* is multiplied by the velocity and added to the displayport offset.
*
* \li\b apz.velocity_relevance_time_ms
* When computing a fling velocity from the most recently stored velocity
* information, only velocities within the most X milliseconds are used.
* This pref controls the value of X.\n
* Units: ms
*
* \li\b apz.x_skate_size_multiplier
* \li\b apz.y_skate_size_multiplier
* The multiplier we apply to the displayport size if it is skating (current
* velocity is above \b apz.min_skate_speed). We prefer to increase the size of
* the Y axis because it is more natural in the case that a user is reading a
* page page that scrolls up/down. Note that one, both or neither of these may be
* used at any instant.\n
* In general we want \b apz.[xy]_skate_size_multiplier to be smaller than the corresponding
* stationary size multiplier because when panning fast we would like to paint
* less and get faster, more predictable paint times. When panning slowly we
* can afford to paint more even though it's slower.
*
* \li\b apz.x_stationary_size_multiplier
* \li\b apz.y_stationary_size_multiplier
* The multiplier we apply to the displayport size if it is not skating (see
* documentation for the skate size multipliers above).
*
* \li\b apz.x_skate_highmem_adjust
* \li\b apz.y_skate_highmem_adjust
* On high memory systems, we adjust the displayport during skating
* to be larger so we can reduce checkerboarding.
*
* \li\b apz.zoom_animation_duration_ms
* This controls how long the zoom-to-rect animation takes.\n
* Units: ms
*
* \li\b apz.scale_repaint_delay_ms
* How long to delay between repaint requests during a scale.
* A negative number prevents repaint requests during a scale.\n
* Units: ms
*
*/
/**
* Computed time function used for sampling frames of a zoom to animation.
*/
StaticAutoPtr<ComputedTimingFunction> gZoomAnimationFunction;
/**
* Computed time function used for curving up velocity when it gets high.
*/
StaticAutoPtr<ComputedTimingFunction> gVelocityCurveFunction;
/**
* The estimated duration of a paint for the purposes of calculating a new
* displayport, in milliseconds.
*/
static const double kDefaultEstimatedPaintDurationMs = 50;
/**
* Returns true if this is a high memory system and we can use
* extra memory for a larger displayport to reduce checkerboarding.
*/
static bool gIsHighMemSystem = false;
static bool IsHighMemSystem()
{
return gIsHighMemSystem;
}
/**
* Is aAngle within the given threshold of the horizontal axis?
* @param aAngle an angle in radians in the range [0, pi]
* @param aThreshold an angle in radians in the range [0, pi/2]
*/
static bool IsCloseToHorizontal(float aAngle, float aThreshold)
{
return (aAngle < aThreshold || aAngle > (M_PI - aThreshold));
}
// As above, but for the vertical axis.
static bool IsCloseToVertical(float aAngle, float aThreshold)
{
return (fabs(aAngle - (M_PI / 2)) < aThreshold);
}
// Counter used to give each APZC a unique id
static uint32_t sAsyncPanZoomControllerCount = 0;
TimeStamp
AsyncPanZoomController::GetFrameTime() const
{
APZCTreeManager* treeManagerLocal = GetApzcTreeManager();
return treeManagerLocal ? treeManagerLocal->GetFrameTime() : TimeStamp::Now();
}
class MOZ_STACK_CLASS StateChangeNotificationBlocker {
public:
explicit StateChangeNotificationBlocker(AsyncPanZoomController* aApzc)
: mApzc(aApzc)
{
ReentrantMonitorAutoEnter lock(mApzc->mMonitor);
mInitialState = mApzc->mState;
mApzc->mNotificationBlockers++;
}
~StateChangeNotificationBlocker()
{
AsyncPanZoomController::PanZoomState newState;
{
ReentrantMonitorAutoEnter lock(mApzc->mMonitor);
mApzc->mNotificationBlockers--;
newState = mApzc->mState;
}
mApzc->DispatchStateChangeNotification(mInitialState, newState);
}
private:
AsyncPanZoomController* mApzc;
AsyncPanZoomController::PanZoomState mInitialState;
};
class ZoomAnimation: public AsyncPanZoomAnimation {
public:
ZoomAnimation(CSSPoint aStartOffset, CSSToParentLayerScale2D aStartZoom,
CSSPoint aEndOffset, CSSToParentLayerScale2D aEndZoom)
: mTotalDuration(TimeDuration::FromMilliseconds(gfxPrefs::APZZoomAnimationDuration()))
, mStartOffset(aStartOffset)
, mStartZoom(aStartZoom)
, mEndOffset(aEndOffset)
, mEndZoom(aEndZoom)
{}
virtual bool DoSample(FrameMetrics& aFrameMetrics,
const TimeDuration& aDelta) override
{
mDuration += aDelta;
double animPosition = mDuration / mTotalDuration;
if (animPosition >= 1.0) {
aFrameMetrics.SetZoom(mEndZoom);
aFrameMetrics.SetScrollOffset(mEndOffset);
return false;
}
// Sample the zoom at the current time point. The sampled zoom
// will affect the final computed resolution.
float sampledPosition =
gZoomAnimationFunction->GetValue(animPosition,
ComputedTimingFunction::BeforeFlag::Unset);
// We scale the scrollOffset linearly with sampledPosition, so the zoom
// needs to scale inversely to match.
aFrameMetrics.SetZoom(CSSToParentLayerScale2D(
1 / (sampledPosition / mEndZoom.xScale + (1 - sampledPosition) / mStartZoom.xScale),
1 / (sampledPosition / mEndZoom.yScale + (1 - sampledPosition) / mStartZoom.yScale)));
aFrameMetrics.SetScrollOffset(CSSPoint::FromUnknownPoint(gfx::Point(
mEndOffset.x * sampledPosition + mStartOffset.x * (1 - sampledPosition),
mEndOffset.y * sampledPosition + mStartOffset.y * (1 - sampledPosition)
)));
return true;
}
virtual bool WantsRepaints() override
{
return false;
}
private:
TimeDuration mDuration;
const TimeDuration mTotalDuration;
// Old metrics from before we started a zoom animation. This is only valid
// when we are in the "ANIMATED_ZOOM" state. This is used so that we can
// interpolate between the start and end frames. We only use the
// |mViewportScrollOffset| and |mResolution| fields on this.
CSSPoint mStartOffset;
CSSToParentLayerScale2D mStartZoom;
// Target metrics for a zoom to animation. This is only valid when we are in
// the "ANIMATED_ZOOM" state. We only use the |mViewportScrollOffset| and
// |mResolution| fields on this.
CSSPoint mEndOffset;
CSSToParentLayerScale2D mEndZoom;
};
class SmoothScrollAnimation : public AsyncPanZoomAnimation {
public:
SmoothScrollAnimation(AsyncPanZoomController& aApzc,
const nsPoint &aInitialPosition,
const nsPoint &aInitialVelocity,
const nsPoint& aDestination, double aSpringConstant,
double aDampingRatio)
: mApzc(aApzc)
, mXAxisModel(aInitialPosition.x, aDestination.x, aInitialVelocity.x,
aSpringConstant, aDampingRatio)
, mYAxisModel(aInitialPosition.y, aDestination.y, aInitialVelocity.y,
aSpringConstant, aDampingRatio)
{
}
/**
* Advances a smooth scroll simulation based on the time passed in |aDelta|.
* This should be called whenever sampling the content transform for this
* frame. Returns true if the smooth scroll should be advanced by one frame,
* or false if the smooth scroll has ended.
*/
bool DoSample(FrameMetrics& aFrameMetrics, const TimeDuration& aDelta) override {
nsPoint oneParentLayerPixel =
CSSPoint::ToAppUnits(ParentLayerPoint(1, 1) / aFrameMetrics.GetZoom());
if (mXAxisModel.IsFinished(oneParentLayerPixel.x) &&
mYAxisModel.IsFinished(oneParentLayerPixel.y)) {
// Set the scroll offset to the exact destination. If we allow the scroll
// offset to end up being a bit off from the destination, we can get
// artefacts like "scroll to the next snap point in this direction"
// scrolling to the snap point we're already supposed to be at.
aFrameMetrics.SetScrollOffset(
aFrameMetrics.CalculateScrollRange().ClampPoint(
CSSPoint::FromAppUnits(nsPoint(mXAxisModel.GetDestination(),
mYAxisModel.GetDestination()))));
return false;
}
mXAxisModel.Simulate(aDelta);
mYAxisModel.Simulate(aDelta);
CSSPoint position = CSSPoint::FromAppUnits(nsPoint(mXAxisModel.GetPosition(),
mYAxisModel.GetPosition()));
CSSPoint css_velocity = CSSPoint::FromAppUnits(nsPoint(mXAxisModel.GetVelocity(),
mYAxisModel.GetVelocity()));
// Convert from points/second to points/ms
ParentLayerPoint velocity = ParentLayerPoint(css_velocity.x, css_velocity.y) / 1000.0f;
// Keep the velocity updated for the Axis class so that any animations
// chained off of the smooth scroll will inherit it.
if (mXAxisModel.IsFinished(oneParentLayerPixel.x)) {
mApzc.mX.SetVelocity(0);
} else {
mApzc.mX.SetVelocity(velocity.x);
}
if (mYAxisModel.IsFinished(oneParentLayerPixel.y)) {
mApzc.mY.SetVelocity(0);
} else {
mApzc.mY.SetVelocity(velocity.y);
}
// If we overscroll, hand off to a fling animation that will complete the
// spring back.
CSSToParentLayerScale2D zoom = aFrameMetrics.GetZoom();
ParentLayerPoint displacement = (position - aFrameMetrics.GetScrollOffset()) * zoom;
ParentLayerPoint overscroll;
ParentLayerPoint adjustedOffset;
mApzc.mX.AdjustDisplacement(displacement.x, adjustedOffset.x, overscroll.x);
mApzc.mY.AdjustDisplacement(displacement.y, adjustedOffset.y, overscroll.y);
aFrameMetrics.ScrollBy(adjustedOffset / zoom);
// The smooth scroll may have caused us to reach the end of our scroll range.
// This can happen if either the layout.css.scroll-behavior.damping-ratio
// preference is set to less than 1 (underdamped) or if a smooth scroll
// inherits velocity from a fling gesture.
if (!IsZero(overscroll)) {
// Hand off a fling with the remaining momentum to the next APZC in the
// overscroll handoff chain.
// We may have reached the end of the scroll range along one axis but
// not the other. In such a case we only want to hand off the relevant
// component of the fling.
if (FuzzyEqualsAdditive(overscroll.x, 0.0f, COORDINATE_EPSILON)) {
velocity.x = 0;
} else if (FuzzyEqualsAdditive(overscroll.y, 0.0f, COORDINATE_EPSILON)) {
velocity.y = 0;
}
// To hand off the fling, we attempt to find a target APZC and start a new
// fling with the same velocity on that APZC. For simplicity, the actual
// overscroll of the current sample is discarded rather than being handed
// off. The compositor should sample animations sufficiently frequently
// that this is not noticeable. The target APZC is chosen by seeing if
// there is an APZC further in the handoff chain which is pannable; if
// there isn't, we take the new fling ourselves, entering an overscrolled
// state.
// Note: APZC is holding mMonitor, so directly calling
// HandleSmoothScrollOverscroll() (which acquires the tree lock) would violate
// the lock ordering. Instead we schedule HandleSmoothScrollOverscroll() to be
// called after mMonitor is released.
mDeferredTasks.AppendElement(
NewRunnableMethod<ParentLayerPoint>(&mApzc,
&AsyncPanZoomController::HandleSmoothScrollOverscroll,
velocity));
return false;
}
return true;
}
void SetDestination(const nsPoint& aNewDestination) {
mXAxisModel.SetDestination(static_cast<int32_t>(aNewDestination.x));
mYAxisModel.SetDestination(static_cast<int32_t>(aNewDestination.y));
}
CSSPoint GetDestination() const {
return CSSPoint::FromAppUnits(
nsPoint(mXAxisModel.GetDestination(), mYAxisModel.GetDestination()));
}
SmoothScrollAnimation* AsSmoothScrollAnimation() override {
return this;
}
private:
AsyncPanZoomController& mApzc;
AxisPhysicsMSDModel mXAxisModel, mYAxisModel;
};
/*static*/ void
AsyncPanZoomController::InitializeGlobalState()
{
static bool sInitialized = false;
if (sInitialized)
return;
sInitialized = true;
MOZ_ASSERT(NS_IsMainThread());
gZoomAnimationFunction = new ComputedTimingFunction();
gZoomAnimationFunction->Init(
nsTimingFunction(NS_STYLE_TRANSITION_TIMING_FUNCTION_EASE));
ClearOnShutdown(&gZoomAnimationFunction);
gVelocityCurveFunction = new ComputedTimingFunction();
gVelocityCurveFunction->Init(
nsTimingFunction(gfxPrefs::APZCurveFunctionX1(),
gfxPrefs::APZCurveFunctionY2(),
gfxPrefs::APZCurveFunctionX2(),
gfxPrefs::APZCurveFunctionY2()));
ClearOnShutdown(&gVelocityCurveFunction);
uint64_t sysmem = PR_GetPhysicalMemorySize();
uint64_t threshold = 1LL << 32; // 4 GB in bytes
gIsHighMemSystem = sysmem >= threshold;
}
AsyncPanZoomController::AsyncPanZoomController(uint64_t aLayersId,
APZCTreeManager* aTreeManager,
const RefPtr<InputQueue>& aInputQueue,
GeckoContentController* aGeckoContentController,
GestureBehavior aGestures)
: mLayersId(aLayersId),
mGeckoContentController(aGeckoContentController),
mRefPtrMonitor("RefPtrMonitor"),
// mTreeManager must be initialized before GetFrameTime() is called
mTreeManager(aTreeManager),
mFrameMetrics(mScrollMetadata.GetMetrics()),
mMonitor("AsyncPanZoomController"),
mLastContentPaintMetrics(mLastContentPaintMetadata.GetMetrics()),
mX(this),
mY(this),
mPanDirRestricted(false),
mZoomConstraints(false, false,
mFrameMetrics.GetDevPixelsPerCSSPixel() * kViewportMinScale / ParentLayerToScreenScale(1),
mFrameMetrics.GetDevPixelsPerCSSPixel() * kViewportMaxScale / ParentLayerToScreenScale(1)),
mLastSampleTime(GetFrameTime()),
mLastCheckerboardReport(GetFrameTime()),
mOverscrollEffect(MakeUnique<OverscrollEffect>(*this)),
mState(NOTHING),
mNotificationBlockers(0),
mInputQueue(aInputQueue),
mPinchPaintTimerSet(false),
mAPZCId(sAsyncPanZoomControllerCount++),
mSharedLock(nullptr),
mAsyncTransformAppliedToContent(false),
mCheckerboardEventLock("APZCBELock")
{
if (aGestures == USE_GESTURE_DETECTOR) {
mGestureEventListener = new GestureEventListener(this);
}
}
AsyncPanZoomController::~AsyncPanZoomController()
{
MOZ_ASSERT(IsDestroyed());
}
PlatformSpecificStateBase*
AsyncPanZoomController::GetPlatformSpecificState()
{
if (!mPlatformSpecificState) {
mPlatformSpecificState = MakeUnique<PlatformSpecificState>();
}
return mPlatformSpecificState.get();
}
already_AddRefed<GeckoContentController>
AsyncPanZoomController::GetGeckoContentController() const {
MonitorAutoLock lock(mRefPtrMonitor);
RefPtr<GeckoContentController> controller = mGeckoContentController;
return controller.forget();
}
already_AddRefed<GestureEventListener>
AsyncPanZoomController::GetGestureEventListener() const {
MonitorAutoLock lock(mRefPtrMonitor);
RefPtr<GestureEventListener> listener = mGestureEventListener;
return listener.forget();
}
const RefPtr<InputQueue>&
AsyncPanZoomController::GetInputQueue() const {
return mInputQueue;
}
void
AsyncPanZoomController::Destroy()
{
APZThreadUtils::AssertOnCompositorThread();
CancelAnimation(CancelAnimationFlags::ScrollSnap);
{ // scope the lock
MonitorAutoLock lock(mRefPtrMonitor);
mGeckoContentController = nullptr;
mGestureEventListener = nullptr;
}
mParent = nullptr;
mTreeManager = nullptr;
// Only send the release message if the SharedFrameMetrics has been created.
if (mMetricsSharingController && mSharedFrameMetricsBuffer) {
Unused << mMetricsSharingController->StopSharingMetrics(mFrameMetrics.GetScrollId(), mAPZCId);
}
{ // scope the lock
ReentrantMonitorAutoEnter lock(mMonitor);
mSharedFrameMetricsBuffer = nullptr;
delete mSharedLock;
mSharedLock = nullptr;
}
}
bool
AsyncPanZoomController::IsDestroyed() const
{
return mTreeManager == nullptr;
}
/* static */ScreenCoord
AsyncPanZoomController::GetTouchStartTolerance()
{
return (gfxPrefs::APZTouchStartTolerance() * APZCTreeManager::GetDPI());
}
/* static */AsyncPanZoomController::AxisLockMode AsyncPanZoomController::GetAxisLockMode()
{
return static_cast<AxisLockMode>(gfxPrefs::APZAxisLockMode());
}
bool
AsyncPanZoomController::ArePointerEventsConsumable(TouchBlockState* aBlock, uint32_t aTouchPoints) {
if (aTouchPoints == 0) {
// Cant' do anything with zero touch points
return false;
}
// This logic is simplified, erring on the side of returning true
// if we're not sure. It's safer to pretend that we can consume the
// event and then not be able to than vice-versa.
// We could probably enhance this logic to determine things like "we're
// not pannable, so we can only zoom in, and the zoom is already maxed
// out, so we're not zoomable either" but no need for that at this point.
bool pannable = aBlock->GetOverscrollHandoffChain()->CanBePanned(this);
bool zoomable = mZoomConstraints.mAllowZoom;
pannable &= (aBlock->TouchActionAllowsPanningX() || aBlock->TouchActionAllowsPanningY());
zoomable &= (aBlock->TouchActionAllowsPinchZoom());
// XXX once we fix bug 1031443, consumable should be assigned
// pannable || zoomable if aTouchPoints > 1.
bool consumable = (aTouchPoints == 1 ? pannable : zoomable);
if (!consumable) {
return false;
}
return true;
}
template <typename Units>
static CoordTyped<Units> GetAxisStart(AsyncDragMetrics::DragDirection aDir, const PointTyped<Units>& aValue) {
if (aDir == AsyncDragMetrics::HORIZONTAL) {
return aValue.x;
} else {
return aValue.y;
}
}
template <typename Units>
static CoordTyped<Units> GetAxisStart(AsyncDragMetrics::DragDirection aDir, const RectTyped<Units>& aValue) {
if (aDir == AsyncDragMetrics::HORIZONTAL) {
return aValue.x;
} else {
return aValue.y;
}
}
template <typename Units>
static IntCoordTyped<Units> GetAxisStart(AsyncDragMetrics::DragDirection aDir, const IntRectTyped<Units>& aValue) {
if (aDir == AsyncDragMetrics::HORIZONTAL) {
return aValue.x;
} else {
return aValue.y;
}
}
template <typename Units>
static IntCoordTyped<Units> GetAxisEnd(AsyncDragMetrics::DragDirection aDir, const IntRectTyped<Units>& aValue) {
if (aDir == AsyncDragMetrics::HORIZONTAL) {
return aValue.x + aValue.width;
} else {
return aValue.y + aValue.height;
}
}
template <typename Units>
static CoordTyped<Units> GetAxisSize(AsyncDragMetrics::DragDirection aDir, const RectTyped<Units>& aValue) {
if (aDir == AsyncDragMetrics::HORIZONTAL) {
return aValue.width;
} else {
return aValue.height;
}
}
template <typename FromUnits, typename ToUnits>
static float GetAxisScale(AsyncDragMetrics::DragDirection aDir, const ScaleFactors2D<FromUnits, ToUnits>& aValue) {
if (aDir == AsyncDragMetrics::HORIZONTAL) {
return aValue.xScale;
} else {
return aValue.yScale;
}
}
nsEventStatus AsyncPanZoomController::HandleDragEvent(const MouseInput& aEvent,
const AsyncDragMetrics& aDragMetrics)
{
if (!gfxPrefs::APZDragEnabled()) {
return nsEventStatus_eIgnore;
}
if (!GetApzcTreeManager()) {
return nsEventStatus_eConsumeNoDefault;
}
RefPtr<HitTestingTreeNode> node =
GetApzcTreeManager()->FindScrollNode(aDragMetrics);
if (!node) {
return nsEventStatus_eConsumeNoDefault;
}
ReentrantMonitorAutoEnter lock(mMonitor);
CSSPoint scrollFramePoint = aEvent.mLocalOrigin / GetFrameMetrics().GetZoom();
// The scrollbar can be transformed with the frame but the pres shell
// resolution is only applied to the scroll frame.
CSSPoint scrollbarPoint = scrollFramePoint * mFrameMetrics.GetPresShellResolution();
CSSRect cssCompositionBound = mFrameMetrics.CalculateCompositedRectInCssPixels();
CSSCoord mousePosition = GetAxisStart(aDragMetrics.mDirection, scrollbarPoint) -
CSSCoord(aDragMetrics.mScrollbarDragOffset) -
GetAxisStart(aDragMetrics.mDirection, cssCompositionBound) -
CSSCoord(GetAxisStart(aDragMetrics.mDirection, aDragMetrics.mScrollTrack));
CSSCoord scrollMax = CSSCoord(GetAxisEnd(aDragMetrics.mDirection, aDragMetrics.mScrollTrack));
scrollMax -= node->GetScrollSize() /
GetAxisScale(aDragMetrics.mDirection, mFrameMetrics.GetZoom()) *
mFrameMetrics.GetPresShellResolution();
float scrollPercent = mousePosition / scrollMax;
CSSCoord minScrollPosition =
GetAxisStart(aDragMetrics.mDirection, mFrameMetrics.GetScrollableRect().TopLeft());
CSSCoord maxScrollPosition =
GetAxisSize(aDragMetrics.mDirection, mFrameMetrics.GetScrollableRect()) -
GetAxisSize(aDragMetrics.mDirection, cssCompositionBound);
CSSCoord scrollPosition = scrollPercent * maxScrollPosition;
scrollPosition = std::max(scrollPosition, minScrollPosition);
scrollPosition = std::min(scrollPosition, maxScrollPosition);
CSSPoint scrollOffset = mFrameMetrics.GetScrollOffset();
if (aDragMetrics.mDirection == AsyncDragMetrics::HORIZONTAL) {
scrollOffset.x = scrollPosition;
} else {
scrollOffset.y = scrollPosition;
}
mFrameMetrics.SetScrollOffset(scrollOffset);
ScheduleCompositeAndMaybeRepaint();
UpdateSharedCompositorFrameMetrics();
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::HandleInputEvent(const InputData& aEvent,
const ScreenToParentLayerMatrix4x4& aTransformToApzc) {
APZThreadUtils::AssertOnControllerThread();
nsEventStatus rv = nsEventStatus_eIgnore;
switch (aEvent.mInputType) {
case MULTITOUCH_INPUT: {
MultiTouchInput multiTouchInput = aEvent.AsMultiTouchInput();
if (!multiTouchInput.TransformToLocal(aTransformToApzc)) {
return rv;
}
RefPtr<GestureEventListener> listener = GetGestureEventListener();
if (listener) {
rv = listener->HandleInputEvent(multiTouchInput);
if (rv == nsEventStatus_eConsumeNoDefault) {
return rv;
}
}
switch (multiTouchInput.mType) {
case MultiTouchInput::MULTITOUCH_START: rv = OnTouchStart(multiTouchInput); break;
case MultiTouchInput::MULTITOUCH_MOVE: rv = OnTouchMove(multiTouchInput); break;
case MultiTouchInput::MULTITOUCH_END: rv = OnTouchEnd(multiTouchInput); break;
case MultiTouchInput::MULTITOUCH_CANCEL: rv = OnTouchCancel(multiTouchInput); break;
default: NS_WARNING("Unhandled multitouch"); break;
}
break;
}
case PANGESTURE_INPUT: {
PanGestureInput panGestureInput = aEvent.AsPanGestureInput();
if (!panGestureInput.TransformToLocal(aTransformToApzc)) {
return rv;
}
switch (panGestureInput.mType) {
case PanGestureInput::PANGESTURE_MAYSTART: rv = OnPanMayBegin(panGestureInput); break;
case PanGestureInput::PANGESTURE_CANCELLED: rv = OnPanCancelled(panGestureInput); break;
case PanGestureInput::PANGESTURE_START: rv = OnPanBegin(panGestureInput); break;
case PanGestureInput::PANGESTURE_PAN: rv = OnPan(panGestureInput, true); break;
case PanGestureInput::PANGESTURE_END: rv = OnPanEnd(panGestureInput); break;
case PanGestureInput::PANGESTURE_MOMENTUMSTART: rv = OnPanMomentumStart(panGestureInput); break;
case PanGestureInput::PANGESTURE_MOMENTUMPAN: rv = OnPan(panGestureInput, false); break;
case PanGestureInput::PANGESTURE_MOMENTUMEND: rv = OnPanMomentumEnd(panGestureInput); break;
default: NS_WARNING("Unhandled pan gesture"); break;
}
break;
}
case MOUSE_INPUT: {
MouseInput mouseInput = aEvent.AsMouseInput();
if (!mouseInput.TransformToLocal(aTransformToApzc)) {
return rv;
}
// TODO Need to implement blocks to properly handle this.
//rv = HandleDragEvent(mouseInput, dragMetrics);
break;
}
case SCROLLWHEEL_INPUT: {
ScrollWheelInput scrollInput = aEvent.AsScrollWheelInput();
if (!scrollInput.TransformToLocal(aTransformToApzc)) {
return rv;
}
rv = OnScrollWheel(scrollInput);
break;
}
case PINCHGESTURE_INPUT: {
PinchGestureInput pinchInput = aEvent.AsPinchGestureInput();
if (!pinchInput.TransformToLocal(aTransformToApzc)) {
return rv;
}
rv = HandleGestureEvent(pinchInput);
break;
}
case TAPGESTURE_INPUT: {
TapGestureInput tapInput = aEvent.AsTapGestureInput();
if (!tapInput.TransformToLocal(aTransformToApzc)) {
return rv;
}
rv = HandleGestureEvent(tapInput);
break;
}
default: NS_WARNING("Unhandled input event type"); break;
}
return rv;
}
nsEventStatus AsyncPanZoomController::HandleGestureEvent(const InputData& aEvent)
{
APZThreadUtils::AssertOnControllerThread();
nsEventStatus rv = nsEventStatus_eIgnore;
switch (aEvent.mInputType) {
case PINCHGESTURE_INPUT: {
const PinchGestureInput& pinchGestureInput = aEvent.AsPinchGestureInput();
switch (pinchGestureInput.mType) {
case PinchGestureInput::PINCHGESTURE_START: rv = OnScaleBegin(pinchGestureInput); break;
case PinchGestureInput::PINCHGESTURE_SCALE: rv = OnScale(pinchGestureInput); break;
case PinchGestureInput::PINCHGESTURE_END: rv = OnScaleEnd(pinchGestureInput); break;
default: NS_WARNING("Unhandled pinch gesture"); break;
}
break;
}
case TAPGESTURE_INPUT: {
const TapGestureInput& tapGestureInput = aEvent.AsTapGestureInput();
switch (tapGestureInput.mType) {
case TapGestureInput::TAPGESTURE_LONG: rv = OnLongPress(tapGestureInput); break;
case TapGestureInput::TAPGESTURE_LONG_UP: rv = OnLongPressUp(tapGestureInput); break;
case TapGestureInput::TAPGESTURE_UP: rv = OnSingleTapUp(tapGestureInput); break;
case TapGestureInput::TAPGESTURE_CONFIRMED: rv = OnSingleTapConfirmed(tapGestureInput); break;
case TapGestureInput::TAPGESTURE_DOUBLE: rv = OnDoubleTap(tapGestureInput); break;
case TapGestureInput::TAPGESTURE_SECOND: rv = OnSecondTap(tapGestureInput); break;
case TapGestureInput::TAPGESTURE_CANCEL: rv = OnCancelTap(tapGestureInput); break;
default: NS_WARNING("Unhandled tap gesture"); break;
}
break;
}
default: NS_WARNING("Unhandled input event"); break;
}
return rv;
}
void AsyncPanZoomController::HandleTouchVelocity(uint32_t aTimesampMs, float aSpeedY)
{
mY.HandleTouchVelocity(aTimesampMs, aSpeedY);
}
nsEventStatus AsyncPanZoomController::OnTouchStart(const MultiTouchInput& aEvent) {
APZC_LOG("%p got a touch-start in state %d\n", this, mState);
mPanDirRestricted = false;
ParentLayerPoint point = GetFirstTouchPoint(aEvent);
switch (mState) {
case FLING:
case ANIMATING_ZOOM:
case SMOOTH_SCROLL:
case OVERSCROLL_ANIMATION:
case WHEEL_SCROLL:
case PAN_MOMENTUM:
MOZ_ASSERT(GetCurrentTouchBlock());
GetCurrentTouchBlock()->GetOverscrollHandoffChain()->CancelAnimations(ExcludeOverscroll);
MOZ_FALLTHROUGH;
case NOTHING: {
mX.StartTouch(point.x, aEvent.mTime);
mY.StartTouch(point.y, aEvent.mTime);
if (RefPtr<GeckoContentController> controller = GetGeckoContentController()) {
MOZ_ASSERT(GetCurrentTouchBlock());
controller->NotifyAPZStateChange(
GetGuid(), APZStateChange::eStartTouch,
GetCurrentTouchBlock()->GetOverscrollHandoffChain()->CanBePanned(this));
}
SetState(TOUCHING);
break;
}
case TOUCHING:
case PANNING:
case PANNING_LOCKED_X:
case PANNING_LOCKED_Y:
case PINCHING:
NS_WARNING("Received impossible touch in OnTouchStart");
break;
default:
NS_WARNING("Unhandled case in OnTouchStart");
break;
}
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnTouchMove(const MultiTouchInput& aEvent) {
APZC_LOG("%p got a touch-move in state %d\n", this, mState);
switch (mState) {
case FLING:
case SMOOTH_SCROLL:
case NOTHING:
case ANIMATING_ZOOM:
// May happen if the user double-taps and drags without lifting after the
// second tap. Ignore the move if this happens.
return nsEventStatus_eIgnore;
case TOUCHING: {
ScreenCoord panThreshold = GetTouchStartTolerance();
UpdateWithTouchAtDevicePoint(aEvent);
if (PanDistance() < panThreshold) {
return nsEventStatus_eIgnore;
}
MOZ_ASSERT(GetCurrentTouchBlock());
if (gfxPrefs::TouchActionEnabled() && GetCurrentTouchBlock()->TouchActionAllowsPanningXY()) {
// User tries to trigger a touch behavior. If allowed touch behavior is vertical pan
// + horizontal pan (touch-action value is equal to AUTO) we can return ConsumeNoDefault
// status immediately to trigger cancel event further. It should happen independent of
// the parent type (whether it is scrolling or not).
StartPanning(aEvent);
return nsEventStatus_eConsumeNoDefault;
}
return StartPanning(aEvent);
}
case PANNING:
case PANNING_LOCKED_X:
case PANNING_LOCKED_Y:
case PAN_MOMENTUM:
TrackTouch(aEvent);
return nsEventStatus_eConsumeNoDefault;
case PINCHING:
// The scale gesture listener should have handled this.
NS_WARNING("Gesture listener should have handled pinching in OnTouchMove.");
return nsEventStatus_eIgnore;
case WHEEL_SCROLL:
case OVERSCROLL_ANIMATION:
// Should not receive a touch-move in the OVERSCROLL_ANIMATION state
// as touch blocks that begin in an overscrolled state cancel the
// animation. The same is true for wheel scroll animations.
NS_WARNING("Received impossible touch in OnTouchMove");
break;
}
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnTouchEnd(const MultiTouchInput& aEvent) {
APZC_LOG("%p got a touch-end in state %d\n", this, mState);
RefPtr<GeckoContentController> controller = GetGeckoContentController();
if (controller) {
controller->SetScrollingRootContent(false);
}
OnTouchEndOrCancel();
// In case no touch behavior triggered previously we can avoid sending
// scroll events or requesting content repaint. This condition is added
// to make tests consistent - in case touch-action is NONE (and therefore
// no pans/zooms can be performed) we expected neither scroll or repaint
// events.
if (mState != NOTHING) {
ReentrantMonitorAutoEnter lock(mMonitor);
}
switch (mState) {
case FLING:
// Should never happen.
NS_WARNING("Received impossible touch end in OnTouchEnd.");
MOZ_FALLTHROUGH;
case ANIMATING_ZOOM:
case SMOOTH_SCROLL:
case NOTHING:
// May happen if the user double-taps and drags without lifting after the
// second tap. Ignore if this happens.
return nsEventStatus_eIgnore;
case TOUCHING:
// We may have some velocity stored on the axis from move events
// that were not big enough to trigger scrolling. Clear that out.
mX.SetVelocity(0);
mY.SetVelocity(0);
MOZ_ASSERT(GetCurrentTouchBlock());
APZC_LOG("%p still has %u touch points active\n", this,
GetCurrentTouchBlock()->GetActiveTouchCount());
// In cases where the user is panning, then taps the second finger without
// entering a pinch, we will arrive here when the second finger is lifted.
// However the first finger is still down so we want to remain in state
// TOUCHING.
if (GetCurrentTouchBlock()->GetActiveTouchCount() == 0) {
// It's possible we may be overscrolled if the user tapped during a
// previous overscroll pan. Make sure to snap back in this situation.
// An ancestor APZC could be overscrolled instead of this APZC, so
// walk the handoff chain as well.
GetCurrentTouchBlock()->GetOverscrollHandoffChain()->SnapBackOverscrolledApzc(this);
// SnapBackOverscrolledApzc() will put any APZC it causes to snap back
// into the OVERSCROLL_ANIMATION state. If that's not us, since we're
// done TOUCHING enter the NOTHING state.
if (mState != OVERSCROLL_ANIMATION) {
SetState(NOTHING);
}
}
return nsEventStatus_eIgnore;
case PANNING:
case PANNING_LOCKED_X:
case PANNING_LOCKED_Y:
case PAN_MOMENTUM:
{
MOZ_ASSERT(GetCurrentTouchBlock());
GetCurrentTouchBlock()->GetOverscrollHandoffChain()->FlushRepaints();
mX.EndTouch(aEvent.mTime);
mY.EndTouch(aEvent.mTime);
ParentLayerPoint flingVelocity = GetVelocityVector();
// Clear our velocities; if DispatchFling() gives the fling to us,
// the fling velocity gets *added* to our existing velocity in
// AcceptFling().
mX.SetVelocity(0);
mY.SetVelocity(0);
// Clear our state so that we don't stay in the PANNING state
// if DispatchFling() gives the fling to somone else. However,
// don't send the state change notification until we've determined
// what our final state is to avoid notification churn.
StateChangeNotificationBlocker blocker(this);
SetState(NOTHING);
APZC_LOG("%p starting a fling animation if %f >= %f\n", this,
flingVelocity.Length().value, gfxPrefs::APZFlingMinVelocityThreshold());
if (flingVelocity.Length() < gfxPrefs::APZFlingMinVelocityThreshold()) {
return nsEventStatus_eConsumeNoDefault;
}
// Make a local copy of the tree manager pointer and check that it's not
// null before calling DispatchFling(). This is necessary because Destroy(),
// which nulls out mTreeManager, could be called concurrently.
if (APZCTreeManager* treeManagerLocal = GetApzcTreeManager()) {
FlingHandoffState handoffState{flingVelocity,
GetCurrentTouchBlock()->GetOverscrollHandoffChain(),
false /* not handoff */,
GetCurrentTouchBlock()->GetScrolledApzc()};
treeManagerLocal->DispatchFling(this, handoffState);
}
return nsEventStatus_eConsumeNoDefault;
}
case PINCHING:
SetState(NOTHING);
// Scale gesture listener should have handled this.
NS_WARNING("Gesture listener should have handled pinching in OnTouchEnd.");
return nsEventStatus_eIgnore;
case WHEEL_SCROLL:
case OVERSCROLL_ANIMATION:
// Should not receive a touch-end in the OVERSCROLL_ANIMATION state
// as touch blocks that begin in an overscrolled state cancel the
// animation. The same is true for WHEEL_SCROLL.
NS_WARNING("Received impossible touch in OnTouchEnd");
break;
}
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnTouchCancel(const MultiTouchInput& aEvent) {
APZC_LOG("%p got a touch-cancel in state %d\n", this, mState);
OnTouchEndOrCancel();
CancelAnimationAndGestureState();
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnScaleBegin(const PinchGestureInput& aEvent) {
APZC_LOG("%p got a scale-begin in state %d\n", this, mState);
mPinchPaintTimerSet = false;
// Note that there may not be a touch block at this point, if we received the
// PinchGestureEvent directly from widget code without any touch events.
if (HasReadyTouchBlock() && !GetCurrentTouchBlock()->TouchActionAllowsPinchZoom()) {
return nsEventStatus_eIgnore;
}
// For platforms that don't support APZ zooming, dispatch a message to the
// content controller, it may want to do something else with this gesture.
if (!gfxPrefs::APZAllowZooming()) {
if (RefPtr<GeckoContentController> controller = GetGeckoContentController()) {
controller->NotifyPinchGesture(aEvent.mType, GetGuid(), 0, aEvent.modifiers);
}
}
SetState(PINCHING);
mX.SetVelocity(0);
mY.SetVelocity(0);
mLastZoomFocus = aEvent.mLocalFocusPoint - mFrameMetrics.GetCompositionBounds().TopLeft();
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnScale(const PinchGestureInput& aEvent) {
APZC_LOG("%p got a scale in state %d\n", this, mState);
if (HasReadyTouchBlock() && !GetCurrentTouchBlock()->TouchActionAllowsPinchZoom()) {
return nsEventStatus_eIgnore;
}
if (mState != PINCHING) {
return nsEventStatus_eConsumeNoDefault;
}
if (!gfxPrefs::APZAllowZooming()) {
if (RefPtr<GeckoContentController> controller = GetGeckoContentController()) {
controller->NotifyPinchGesture(aEvent.mType, GetGuid(),
ViewAs<LayoutDevicePixel>(aEvent.mCurrentSpan - aEvent.mPreviousSpan,
PixelCastJustification::LayoutDeviceIsParentLayerForRCDRSF),
aEvent.modifiers);
}
}
// Only the root APZC is zoomable, and the root APZC is not allowed to have
// different x and y scales. If it did, the calculations in this function
// would have to be adjusted (as e.g. it would no longer be valid to take
// the minimum or maximum of the ratios of the widths and heights of the
// page rect and the composition bounds).
MOZ_ASSERT(mFrameMetrics.IsRootContent());
MOZ_ASSERT(mFrameMetrics.GetZoom().AreScalesSame());
{
ReentrantMonitorAutoEnter lock(mMonitor);
CSSToParentLayerScale userZoom = mFrameMetrics.GetZoom().ToScaleFactor();
ParentLayerPoint focusPoint = aEvent.mLocalFocusPoint - mFrameMetrics.GetCompositionBounds().TopLeft();
CSSPoint cssFocusPoint = focusPoint / mFrameMetrics.GetZoom();
ParentLayerPoint focusChange = mLastZoomFocus - focusPoint;
mLastZoomFocus = focusPoint;
// If displacing by the change in focus point will take us off page bounds,
// then reduce the displacement such that it doesn't.
focusChange.x -= mX.DisplacementWillOverscrollAmount(focusChange.x);
focusChange.y -= mY.DisplacementWillOverscrollAmount(focusChange.y);
ScrollBy(focusChange / userZoom);
// If the span is zero or close to it, we don't want to process this zoom
// change because we're going to get wonky numbers for the spanRatio. So
// let's bail out here. Note that we do this after the focus-change-scroll
// above, so that if we have a pinch with zero span but changing focus,
// such as generated by some Synaptics touchpads on Windows, we still
// scroll properly.
float prevSpan = aEvent.mPreviousSpan;
if (fabsf(prevSpan) <= EPSILON || fabsf(aEvent.mCurrentSpan) <= EPSILON) {
// We might have done a nonzero ScrollBy above, so update metrics and
// repaint/recomposite
ScheduleCompositeAndMaybeRepaint();
UpdateSharedCompositorFrameMetrics();
return nsEventStatus_eConsumeNoDefault;
}
float spanRatio = aEvent.mCurrentSpan / aEvent.mPreviousSpan;
// When we zoom in with focus, we can zoom too much towards the boundaries
// that we actually go over them. These are the needed displacements along
// either axis such that we don't overscroll the boundaries when zooming.
CSSPoint neededDisplacement;
CSSToParentLayerScale realMinZoom = mZoomConstraints.mMinZoom;
CSSToParentLayerScale realMaxZoom = mZoomConstraints.mMaxZoom;
realMinZoom.scale = std::max(realMinZoom.scale,
mFrameMetrics.GetCompositionBounds().width / mFrameMetrics.GetScrollableRect().width);
realMinZoom.scale = std::max(realMinZoom.scale,
mFrameMetrics.GetCompositionBounds().height / mFrameMetrics.GetScrollableRect().height);
if (realMaxZoom < realMinZoom) {
realMaxZoom = realMinZoom;
}
bool doScale = (spanRatio > 1.0 && userZoom < realMaxZoom) ||
(spanRatio < 1.0 && userZoom > realMinZoom);
if (!mZoomConstraints.mAllowZoom) {
doScale = false;
}
if (doScale) {
spanRatio = clamped(spanRatio,
realMinZoom.scale / userZoom.scale,
realMaxZoom.scale / userZoom.scale);
// Note that the spanRatio here should never put us into OVERSCROLL_BOTH because
// up above we clamped it.
neededDisplacement.x = -mX.ScaleWillOverscrollAmount(spanRatio, cssFocusPoint.x);
neededDisplacement.y = -mY.ScaleWillOverscrollAmount(spanRatio, cssFocusPoint.y);
ScaleWithFocus(spanRatio, cssFocusPoint);
if (neededDisplacement != CSSPoint()) {
ScrollBy(neededDisplacement);
}
// We don't want to redraw on every scale, so throttle it.
if (!mPinchPaintTimerSet) {
const int delay = gfxPrefs::APZScaleRepaintDelay();
if (delay >= 0) {
if (RefPtr<GeckoContentController> controller = GetGeckoContentController()) {
mPinchPaintTimerSet = true;
controller->PostDelayedTask(
NewRunnableMethod(this,
&AsyncPanZoomController::DoDelayedRequestContentRepaint),
delay);
}
}
}
UpdateSharedCompositorFrameMetrics();
}
// We did a ScrollBy call above even if we didn't do a scale, so we
// should composite for that.
ScheduleComposite();
}
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnScaleEnd(const PinchGestureInput& aEvent) {
APZC_LOG("%p got a scale-end in state %d\n", this, mState);
mPinchPaintTimerSet = false;
if (HasReadyTouchBlock() && !GetCurrentTouchBlock()->TouchActionAllowsPinchZoom()) {
return nsEventStatus_eIgnore;
}
if (!gfxPrefs::APZAllowZooming()) {
if (RefPtr<GeckoContentController> controller = GetGeckoContentController()) {
controller->NotifyPinchGesture(aEvent.mType, GetGuid(), 0, aEvent.modifiers);
}
}
SetState(NOTHING);
{
ReentrantMonitorAutoEnter lock(mMonitor);
ScheduleComposite();
RequestContentRepaint();
UpdateSharedCompositorFrameMetrics();
}
// Non-negative focus point would indicate that one finger is still down
if (aEvent.mLocalFocusPoint.x != -1 && aEvent.mLocalFocusPoint.y != -1) {
mPanDirRestricted = false;
mX.StartTouch(aEvent.mLocalFocusPoint.x, aEvent.mTime);
mY.StartTouch(aEvent.mLocalFocusPoint.y, aEvent.mTime);
SetState(TOUCHING);
} else {
// Otherwise, handle the fingers being lifted.
ReentrantMonitorAutoEnter lock(mMonitor);
// We can get into a situation where we are overscrolled at the end of a
// pinch if we go into overscroll with a two-finger pan, and then turn
// that into a pinch by increasing the span sufficiently. In such a case,
// there is no snap-back animation to get us out of overscroll, so we need
// to get out of it somehow.
// Moreover, in cases of scroll handoff, the overscroll can be on an APZC
// further up in the handoff chain rather than on the current APZC, so
// we need to clear overscroll along the entire handoff chain.
if (HasReadyTouchBlock()) {
GetCurrentTouchBlock()->GetOverscrollHandoffChain()->ClearOverscroll();
} else {
ClearOverscroll();
}
// Along with clearing the overscroll, we also want to snap to the nearest
// snap point as appropriate.
ScrollSnap();
}
return nsEventStatus_eConsumeNoDefault;
}
bool
AsyncPanZoomController::ConvertToGecko(const ScreenIntPoint& aPoint, LayoutDevicePoint* aOut)
{
if (APZCTreeManager* treeManagerLocal = GetApzcTreeManager()) {
ScreenToScreenMatrix4x4 transformScreenToGecko =
treeManagerLocal->GetScreenToApzcTransform(this)
* treeManagerLocal->GetApzcToGeckoTransform(this);
Maybe<ScreenIntPoint> layoutPoint = UntransformBy(
transformScreenToGecko, aPoint);
if (!layoutPoint) {
return false;
}
*aOut = LayoutDevicePoint(ViewAs<LayoutDevicePixel>(*layoutPoint,
PixelCastJustification::LayoutDeviceIsScreenForUntransformedEvent));
return true;
}
return false;
}
static bool
AllowsScrollingMoreThanOnePage(double aMultiplier)
{
const int32_t kMinAllowPageScroll =
EventStateManager::MIN_MULTIPLIER_VALUE_ALLOWING_OVER_ONE_PAGE_SCROLL;
return Abs(aMultiplier) >= kMinAllowPageScroll;
}
ParentLayerPoint
AsyncPanZoomController::GetScrollWheelDelta(const ScrollWheelInput& aEvent) const
{
ParentLayerSize scrollAmount;
ParentLayerSize pageScrollSize;
{
// Grab the lock to access the frame metrics.
ReentrantMonitorAutoEnter lock(mMonitor);
LayoutDeviceIntSize scrollAmountLD = mScrollMetadata.GetLineScrollAmount();
LayoutDeviceIntSize pageScrollSizeLD = mScrollMetadata.GetPageScrollAmount();
scrollAmount = scrollAmountLD /
mFrameMetrics.GetDevPixelsPerCSSPixel() * mFrameMetrics.GetZoom();
pageScrollSize = pageScrollSizeLD /
mFrameMetrics.GetDevPixelsPerCSSPixel() * mFrameMetrics.GetZoom();
}
ParentLayerPoint delta;
switch (aEvent.mDeltaType) {
case ScrollWheelInput::SCROLLDELTA_LINE: {
delta.x = aEvent.mDeltaX * scrollAmount.width;
delta.y = aEvent.mDeltaY * scrollAmount.height;
break;
}
case ScrollWheelInput::SCROLLDELTA_PAGE: {
delta.x = aEvent.mDeltaX * pageScrollSize.width;
delta.y = aEvent.mDeltaY * pageScrollSize.height;
break;
}
case ScrollWheelInput::SCROLLDELTA_PIXEL: {
delta = ToParentLayerCoordinates(ScreenPoint(aEvent.mDeltaX, aEvent.mDeltaY), aEvent.mOrigin);
break;
}
default:
MOZ_ASSERT_UNREACHABLE("unexpected scroll delta type");
}
// Apply user-set multipliers.
delta.x *= aEvent.mUserDeltaMultiplierX;
delta.y *= aEvent.mUserDeltaMultiplierY;
// For the conditions under which we allow system scroll overrides, see
// EventStateManager::DeltaAccumulator::ComputeScrollAmountForDefaultAction
// and WheelTransaction::OverrideSystemScrollSpeed. Note that we do *not*
// restrict this to the root content, see bug 1217715 for discussion on this.
if (gfxPrefs::MouseWheelHasRootScrollDeltaOverride() &&
!aEvent.IsCustomizedByUserPrefs() &&
aEvent.mDeltaType == ScrollWheelInput::SCROLLDELTA_LINE &&
aEvent.mAllowToOverrideSystemScrollSpeed) {
delta.x = WidgetWheelEvent::ComputeOverriddenDelta(delta.x, false);
delta.y = WidgetWheelEvent::ComputeOverriddenDelta(delta.y, true);
}
// If this is a line scroll, and this event was part of a scroll series, then
// it might need extra acceleration. See WheelHandlingHelper.cpp.
if (aEvent.mDeltaType == ScrollWheelInput::SCROLLDELTA_LINE &&
aEvent.mScrollSeriesNumber > 0)
{
int32_t start = gfxPrefs::MouseWheelAccelerationStart();
if (start >= 0 && aEvent.mScrollSeriesNumber >= uint32_t(start)) {
int32_t factor = gfxPrefs::MouseWheelAccelerationFactor();
if (factor > 0) {
delta.x = ComputeAcceleratedWheelDelta(delta.x, aEvent.mScrollSeriesNumber, factor);
delta.y = ComputeAcceleratedWheelDelta(delta.y, aEvent.mScrollSeriesNumber, factor);
}
}
}
// We shouldn't scroll more than one page at once except when the
// user preference is large.
if (!AllowsScrollingMoreThanOnePage(aEvent.mUserDeltaMultiplierX) &&
Abs(delta.x) > pageScrollSize.width) {
delta.x = (delta.x >= 0)
? pageScrollSize.width
: -pageScrollSize.width;
}
if (!AllowsScrollingMoreThanOnePage(aEvent.mUserDeltaMultiplierY) &&
Abs(delta.y) > pageScrollSize.height) {
delta.y = (delta.y >= 0)
? pageScrollSize.height
: -pageScrollSize.height;
}
return delta;
}
// Return whether or not the underlying layer can be scrolled on either axis.
bool
AsyncPanZoomController::CanScroll(const InputData& aEvent) const
{
ParentLayerPoint delta;
if (aEvent.mInputType == SCROLLWHEEL_INPUT) {
delta = GetScrollWheelDelta(aEvent.AsScrollWheelInput());
} else if (aEvent.mInputType == PANGESTURE_INPUT) {
const PanGestureInput& panInput = aEvent.AsPanGestureInput();
delta = ToParentLayerCoordinates(panInput.UserMultipliedPanDisplacement(), panInput.mPanStartPoint);
}
if (!delta.x && !delta.y) {
return false;
}
return CanScrollWithWheel(delta);
}
bool
AsyncPanZoomController::CanScrollWithWheel(const ParentLayerPoint& aDelta) const
{
ReentrantMonitorAutoEnter lock(mMonitor);
if (mX.CanScroll(aDelta.x)) {
return true;
}
if (mY.CanScroll(aDelta.y) && mScrollMetadata.AllowVerticalScrollWithWheel()) {
return true;
}
return false;
}
bool
AsyncPanZoomController::CanScroll(Layer::ScrollDirection aDirection) const
{
ReentrantMonitorAutoEnter lock(mMonitor);
switch (aDirection) {
case Layer::HORIZONTAL: return mX.CanScroll();
case Layer::VERTICAL: return mY.CanScroll();
default: MOZ_ASSERT(false); return false;
}
}
bool
AsyncPanZoomController::AllowScrollHandoffInCurrentBlock() const
{
bool result = mInputQueue->AllowScrollHandoff();
if (!gfxPrefs::APZAllowImmediateHandoff()) {
if (InputBlockState* currentBlock = GetCurrentInputBlock()) {
// Do not allow handoff beyond the first APZC to scroll.
if (currentBlock->GetScrolledApzc() == this) {
result = false;
}
}
}
return result;
}
void AsyncPanZoomController::DoDelayedRequestContentRepaint()
{
if (!IsDestroyed() && mPinchPaintTimerSet) {
ReentrantMonitorAutoEnter lock(mMonitor);
RequestContentRepaint();
}
mPinchPaintTimerSet = false;
}
nsEventStatus AsyncPanZoomController::OnScrollWheel(const ScrollWheelInput& aEvent)
{
ParentLayerPoint delta = GetScrollWheelDelta(aEvent);
APZC_LOG("%p got a scroll-wheel with delta %s\n", this, Stringify(delta).c_str());
if ((delta.x || delta.y) && !CanScrollWithWheel(delta)) {
// We can't scroll this apz anymore, so we simply drop the event.
if (mInputQueue->GetActiveWheelTransaction() &&
gfxPrefs::MouseScrollTestingEnabled()) {
if (RefPtr<GeckoContentController> controller = GetGeckoContentController()) {
controller->NotifyMozMouseScrollEvent(
mFrameMetrics.GetScrollId(),
NS_LITERAL_STRING("MozMouseScrollFailed"));
}
}
return nsEventStatus_eConsumeNoDefault;
}
if (delta.x == 0 && delta.y == 0) {
// Avoid spurious state changes and unnecessary work
return nsEventStatus_eIgnore;
}
switch (aEvent.mScrollMode) {
case ScrollWheelInput::SCROLLMODE_INSTANT: {
// Wheel events from "clicky" mouse wheels trigger scroll snapping to the
// next snap point. Check for this, and adjust the delta to take into
// account the snap point.
CSSPoint startPosition = mFrameMetrics.GetScrollOffset();
MaybeAdjustDeltaForScrollSnapping(aEvent, delta, startPosition);
ScreenPoint distance = ToScreenCoordinates(
ParentLayerPoint(fabs(delta.x), fabs(delta.y)), aEvent.mLocalOrigin);
CancelAnimation();
MOZ_ASSERT(mInputQueue->GetCurrentWheelBlock());
OverscrollHandoffState handoffState(
*mInputQueue->GetCurrentWheelBlock()->GetOverscrollHandoffChain(),
distance,
ScrollSource::Wheel);
ParentLayerPoint startPoint = aEvent.mLocalOrigin;
ParentLayerPoint endPoint = aEvent.mLocalOrigin - delta;
CallDispatchScroll(startPoint, endPoint, handoffState);
SetState(NOTHING);
// The calls above handle their own locking; moreover,
// ToScreenCoordinates() and CallDispatchScroll() can grab the tree lock.
ReentrantMonitorAutoEnter lock(mMonitor);
RequestContentRepaint();
break;
}
case ScrollWheelInput::SCROLLMODE_SMOOTH: {
// The lock must be held across the entire update operation, so the
// compositor doesn't end the animation before we get a chance to
// update it.
ReentrantMonitorAutoEnter lock(mMonitor);
// Perform scroll snapping if appropriate.
CSSPoint startPosition = mFrameMetrics.GetScrollOffset();
// If we're already in a wheel scroll or smooth scroll animation,
// the delta is applied to its destination, not to the current
// scroll position. Take this into account when finding a snap point.
if (mState == WHEEL_SCROLL) {
startPosition = mAnimation->AsWheelScrollAnimation()->GetDestination();
} else if (mState == SMOOTH_SCROLL) {
startPosition = mAnimation->AsSmoothScrollAnimation()->GetDestination();
}
if (MaybeAdjustDeltaForScrollSnapping(aEvent, delta, startPosition)) {
// If we're scroll snapping, use a smooth scroll animation to get
// the desired physics. Note that SmoothScrollTo() will re-use an
// existing smooth scroll animation if there is one.
APZC_LOG("%p wheel scrolling to snap point %s\n", this, Stringify(startPosition).c_str());
SmoothScrollTo(startPosition);
break;
}
// Otherwise, use a wheel scroll animation, also reusing one if possible.
if (mState != WHEEL_SCROLL) {
CancelAnimation();
SetState(WHEEL_SCROLL);
nsPoint initialPosition = CSSPoint::ToAppUnits(mFrameMetrics.GetScrollOffset());
StartAnimation(new WheelScrollAnimation(
*this, initialPosition, aEvent.mDeltaType));
}
nsPoint deltaInAppUnits =
CSSPoint::ToAppUnits(delta / mFrameMetrics.GetZoom());
// Cast velocity from ParentLayerPoints/ms to CSSPoints/ms then convert to
// appunits/second
nsPoint velocity =
CSSPoint::ToAppUnits(CSSPoint(mX.GetVelocity(), mY.GetVelocity())) * 1000.0f;
WheelScrollAnimation* animation = mAnimation->AsWheelScrollAnimation();
animation->Update(aEvent.mTimeStamp, deltaInAppUnits, nsSize(velocity.x, velocity.y));
break;
}
case ScrollWheelInput::SCROLLMODE_SENTINEL: {
MOZ_ASSERT_UNREACHABLE("Invalid ScrollMode.");
break;
}
}
return nsEventStatus_eConsumeNoDefault;
}
void
AsyncPanZoomController::NotifyMozMouseScrollEvent(const nsString& aString) const
{
RefPtr<GeckoContentController> controller = GetGeckoContentController();
if (!controller) {
return;
}
controller->NotifyMozMouseScrollEvent(mFrameMetrics.GetScrollId(), aString);
}
nsEventStatus AsyncPanZoomController::OnPanMayBegin(const PanGestureInput& aEvent) {
APZC_LOG("%p got a pan-maybegin in state %d\n", this, mState);
mX.StartTouch(aEvent.mLocalPanStartPoint.x, aEvent.mTime);
mY.StartTouch(aEvent.mLocalPanStartPoint.y, aEvent.mTime);
MOZ_ASSERT(GetCurrentPanGestureBlock());
GetCurrentPanGestureBlock()->GetOverscrollHandoffChain()->CancelAnimations();
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnPanCancelled(const PanGestureInput& aEvent) {
APZC_LOG("%p got a pan-cancelled in state %d\n", this, mState);
mX.CancelGesture();
mY.CancelGesture();
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnPanBegin(const PanGestureInput& aEvent) {
APZC_LOG("%p got a pan-begin in state %d\n", this, mState);
if (mState == SMOOTH_SCROLL) {
// SMOOTH_SCROLL scrolls are cancelled by pan gestures.
CancelAnimation();
}
mX.StartTouch(aEvent.mLocalPanStartPoint.x, aEvent.mTime);
mY.StartTouch(aEvent.mLocalPanStartPoint.y, aEvent.mTime);
if (GetAxisLockMode() == FREE) {
SetState(PANNING);
return nsEventStatus_eConsumeNoDefault;
}
float dx = aEvent.mPanDisplacement.x, dy = aEvent.mPanDisplacement.y;
if (dx || dy) {
double angle = atan2(dy, dx); // range [-pi, pi]
angle = fabs(angle); // range [0, pi]
HandlePanning(angle);
} else {
SetState(PANNING);
}
// Call into OnPan in order to process any delta included in this event.
OnPan(aEvent, true);
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnPan(const PanGestureInput& aEvent, bool aFingersOnTouchpad) {
APZC_LOG("%p got a pan-pan in state %d\n", this, mState);
if (mState == SMOOTH_SCROLL) {
if (!aFingersOnTouchpad) {
// When a SMOOTH_SCROLL scroll is being processed on a frame, mouse
// wheel and trackpad momentum scroll position updates will not cancel the
// SMOOTH_SCROLL scroll animations, enabling scripts that depend on
// them to be responsive without forcing the user to wait for the momentum
// scrolling to completely stop.
return nsEventStatus_eConsumeNoDefault;
}
// SMOOTH_SCROLL scrolls are cancelled by pan gestures.
CancelAnimation();
}
if (mState == NOTHING) {
// This event block was interrupted by something else. If the user's fingers
// are still on on the touchpad we want to resume scrolling, otherwise we
// ignore the rest of the scroll gesture.
if (!aFingersOnTouchpad) {
return nsEventStatus_eConsumeNoDefault;
}
// Resume / restart the pan.
// PanBegin will call back into this function with mState == PANNING.
return OnPanBegin(aEvent);
}
// Note that there is a multiplier that applies onto the "physical" pan
// displacement (how much the user's fingers moved) that produces the "logical"
// pan displacement (how much the page should move). For some of the code
// below it makes more sense to use the physical displacement rather than
// the logical displacement, and vice-versa.
ScreenPoint physicalPanDisplacement = aEvent.mPanDisplacement;
ParentLayerPoint logicalPanDisplacement = aEvent.UserMultipliedLocalPanDisplacement();
// We need to update the axis velocity in order to get a useful display port
// size and position. We need to do so even if this is a momentum pan (i.e.
// aFingersOnTouchpad == false); in that case the "with touch" part is not
// really appropriate, so we may want to rethink this at some point.
mX.UpdateWithTouchAtDevicePoint(aEvent.mLocalPanStartPoint.x, logicalPanDisplacement.x, aEvent.mTime);
mY.UpdateWithTouchAtDevicePoint(aEvent.mLocalPanStartPoint.y, logicalPanDisplacement.y, aEvent.mTime);
HandlePanningUpdate(physicalPanDisplacement);
ScreenPoint panDistance(fabs(physicalPanDisplacement.x), fabs(physicalPanDisplacement.y));
MOZ_ASSERT(GetCurrentPanGestureBlock());
OverscrollHandoffState handoffState(
*GetCurrentPanGestureBlock()->GetOverscrollHandoffChain(),
panDistance,
ScrollSource::Wheel);
// Create fake "touch" positions that will result in the desired scroll motion.
// Note that the pan displacement describes the change in scroll position:
// positive displacement values mean that the scroll position increases.
// However, an increase in scroll position means that the scrolled contents
// are moved to the left / upwards. Since our simulated "touches" determine
// the motion of the scrolled contents, not of the scroll position, they need
// to move in the opposite direction of the pan displacement.
ParentLayerPoint startPoint = aEvent.mLocalPanStartPoint;
ParentLayerPoint endPoint = aEvent.mLocalPanStartPoint - logicalPanDisplacement;
CallDispatchScroll(startPoint, endPoint, handoffState);
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnPanEnd(const PanGestureInput& aEvent) {
APZC_LOG("%p got a pan-end in state %d\n", this, mState);
// Call into OnPan in order to process any delta included in this event.
OnPan(aEvent, true);
mX.EndTouch(aEvent.mTime);
mY.EndTouch(aEvent.mTime);
// Drop any velocity on axes where we don't have room to scroll anyways
// (in this APZC, or an APZC further in the handoff chain).
// This ensures that we don't enlarge the display port unnecessarily.
MOZ_ASSERT(GetCurrentPanGestureBlock());
RefPtr<const OverscrollHandoffChain> overscrollHandoffChain =
GetCurrentPanGestureBlock()->GetOverscrollHandoffChain();
if (!overscrollHandoffChain->CanScrollInDirection(this, Layer::HORIZONTAL)) {
mX.SetVelocity(0);
}
if (!overscrollHandoffChain->CanScrollInDirection(this, Layer::VERTICAL)) {
mY.SetVelocity(0);
}
SetState(NOTHING);
RequestContentRepaint();
if (!aEvent.mFollowedByMomentum) {
ScrollSnap();
}
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnPanMomentumStart(const PanGestureInput& aEvent) {
APZC_LOG("%p got a pan-momentumstart in state %d\n", this, mState);
if (mState == SMOOTH_SCROLL) {
// SMOOTH_SCROLL scrolls are cancelled by pan gestures.
CancelAnimation();
}
SetState(PAN_MOMENTUM);
ScrollSnapToDestination();
// Call into OnPan in order to process any delta included in this event.
OnPan(aEvent, false);
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnPanMomentumEnd(const PanGestureInput& aEvent) {
APZC_LOG("%p got a pan-momentumend in state %d\n", this, mState);
// Call into OnPan in order to process any delta included in this event.
OnPan(aEvent, false);
// We need to reset the velocity to zero. We don't really have a "touch"
// here because the touch has already ended long before the momentum
// animation started, but I guess it doesn't really matter for now.
mX.CancelGesture();
mY.CancelGesture();
SetState(NOTHING);
RequestContentRepaint();
return nsEventStatus_eConsumeNoDefault;
}
nsEventStatus AsyncPanZoomController::OnLongPress(const TapGestureInput& aEvent) {
APZC_LOG("%p got a long-press in state %d\n", this, mState);
RefPtr<GeckoContentController> controller = GetGeckoContentController();
if (controller) {
LayoutDevicePoint geckoScreenPoint;
if (ConvertToGecko(aEvent.mPoint, &geckoScreenPoint)) {
TouchBlockState* touch = GetCurrentTouchBlock();
if (!touch) {
APZC_LOG("%p dropping long-press because some non-touch block interrupted it\n", this);
return nsEventStatus_eIgnore;
}
if (touch->IsDuringFastFling()) {
APZC_LOG("%p dropping long-press because of fast fling\n", this);
return nsEventStatus_eIgnore;
}
uint64_t blockId = GetInputQueue()->InjectNewTouchBlock(this);
controller->HandleTap(TapType::eLongTap, geckoScreenPoint, aEvent.modifiers, GetGuid(), blockId);
return nsEventStatus_eConsumeNoDefault;
}
}
return nsEventStatus_eIgnore;
}
nsEventStatus AsyncPanZoomController::OnLongPressUp(const TapGestureInput& aEvent) {
APZC_LOG("%p got a long-tap-up in state %d\n", this, mState);
return GenerateSingleTap(TapType::eLongTapUp, aEvent.mPoint, aEvent.modifiers);
}
nsEventStatus AsyncPanZoomController::GenerateSingleTap(TapType aType,
const ScreenIntPoint& aPoint, mozilla::Modifiers aModifiers) {
RefPtr<GeckoContentController> controller = GetGeckoContentController();
if (controller) {
LayoutDevicePoint geckoScreenPoint;
if (ConvertToGecko(aPoint, &geckoScreenPoint)) {
TouchBlockState* touch = GetCurrentTouchBlock();
// |touch| may be null in the case where this function is
// invoked by GestureEventListener on a timeout. In that case we already
// verified that the single tap is allowed so we let it through.
// XXX there is a bug here that in such a case the touch block that
// generated this tap will not get its mSingleTapOccurred flag set.
// See https://bugzilla.mozilla.org/show_bug.cgi?id=1256344#c6
if (touch) {
if (touch->IsDuringFastFling()) {
APZC_LOG("%p dropping single-tap because it was during a fast-fling\n", this);
return nsEventStatus_eIgnore;
}
touch->SetSingleTapOccurred();
}
// Because this may be being running as part of APZCTreeManager::ReceiveInputEvent,
// calling controller->HandleTap directly might mean that content receives
// the single tap message before the corresponding touch-up. To avoid that we
// schedule the singletap message to run on the next spin of the event loop.
// See bug 965381 for the issue this was causing.
RefPtr<Runnable> runnable =
NewRunnableMethod<TapType, LayoutDevicePoint, mozilla::Modifiers,
ScrollableLayerGuid, uint64_t>(controller,
&GeckoContentController::HandleTap,
aType, geckoScreenPoint,
aModifiers, GetGuid(),
touch ? touch->GetBlockId() : 0);
controller->PostDelayedTask(runnable.forget(), 0);
return nsEventStatus_eConsumeNoDefault;
}
}
return nsEventStatus_eIgnore;
}
void AsyncPanZoomController::OnTouchEndOrCancel() {
if (RefPtr<GeckoContentController> controller = GetGeckoContentController()) {
MOZ_ASSERT(GetCurrentTouchBlock());
controller->NotifyAPZStateChange(
GetGuid(), APZStateChange::eEndTouch, GetCurrentTouchBlock()->SingleTapOccurred());
}
}
nsEventStatus AsyncPanZoomController::OnSingleTapUp(const TapGestureInput& aEvent) {
APZC_LOG("%p got a single-tap-up in state %d\n", this, mState);
// If mZoomConstraints.mAllowDoubleTapZoom is true we wait for a call to OnSingleTapConfirmed before
// sending event to content
MOZ_ASSERT(GetCurrentTouchBlock());
if (!(mZoomConstraints.mAllowDoubleTapZoom && GetCurrentTouchBlock()->TouchActionAllowsDoubleTapZoom())) {
return GenerateSingleTap(TapType::eSingleTap, aEvent.mPoint, aEvent.modifiers);
}
return nsEventStatus_eIgnore;
}
nsEventStatus AsyncPanZoomController::OnSingleTapConfirmed(const TapGestureInput& aEvent) {
APZC_LOG("%p got a single-tap-confirmed in state %d\n", this, mState);
return GenerateSingleTap(TapType::eSingleTap, aEvent.mPoint, aEvent.modifiers);
}
nsEventStatus AsyncPanZoomController::OnDoubleTap(const TapGestureInput& aEvent) {
APZC_LOG("%p got a double-tap in state %d\n", this, mState);
RefPtr<GeckoContentController> controller = GetGeckoContentController();
if (controller) {
MOZ_ASSERT(GetCurrentTouchBlock());
if (mZoomConstraints.mAllowDoubleTapZoom && GetCurrentTouchBlock()->TouchActionAllowsDoubleTapZoom()) {
LayoutDevicePoint geckoScreenPoint;
if (ConvertToGecko(aEvent.mPoint, &geckoScreenPoint)) {
controller->HandleTap(TapType::eDoubleTap, geckoScreenPoint,
aEvent.modifiers, GetGuid(), GetCurrentTouchBlock()->GetBlockId());
}
}
return nsEventStatus_eConsumeNoDefault;
}
return nsEventStatus_eIgnore;
}
nsEventStatus AsyncPanZoomController::OnSecondTap(const TapGestureInput& aEvent)
{
APZC_LOG("%p got a second-tap in state %d\n", this, mState);
return GenerateSingleTap(TapType::eSecondTap, aEvent.mPoint, aEvent.modifiers);
}
nsEventStatus AsyncPanZoomController::OnCancelTap(const TapGestureInput& aEvent) {
APZC_LOG("%p got a cancel-tap in state %d\n", this, mState);
// XXX: Implement this.
return nsEventStatus_eIgnore;
}
ScreenToParentLayerMatrix4x4 AsyncPanZoomController::GetTransformToThis() const {
if (APZCTreeManager* treeManagerLocal = GetApzcTreeManager()) {
return treeManagerLocal->GetScreenToApzcTransform(this);
}
return ScreenToParentLayerMatrix4x4();
}
ScreenPoint AsyncPanZoomController::ToScreenCoordinates(const ParentLayerPoint& aVector,
const ParentLayerPoint& aAnchor) const {
return TransformVector(GetTransformToThis().Inverse(), aVector, aAnchor);
}
// TODO: figure out a good way to check the w-coordinate is positive and return the result
ParentLayerPoint AsyncPanZoomController::ToParentLayerCoordinates(const ScreenPoint& aVector,
const ScreenPoint& aAnchor) const {
return TransformVector(GetTransformToThis(), aVector, aAnchor);
}
bool AsyncPanZoomController::Contains(const ScreenIntPoint& aPoint) const
{
ScreenToParentLayerMatrix4x4 transformToThis = GetTransformToThis();
Maybe<ParentLayerIntPoint> point = UntransformBy(transformToThis, aPoint);
if (!point) {
return false;
}
ParentLayerIntRect cb;
{
ReentrantMonitorAutoEnter lock(mMonitor);
GetFrameMetrics().GetCompositionBounds().ToIntRect(&cb);
}
return cb.Contains(*point);
}
ScreenCoord AsyncPanZoomController::PanDistance() const {
ParentLayerPoint panVector;
ParentLayerPoint panStart;
{
ReentrantMonitorAutoEnter lock(mMonitor);
panVector = ParentLayerPoint(mX.PanDistance(), mY.PanDistance());
panStart = PanStart();
}
return ToScreenCoordinates(panVector, panStart).Length();
}
ParentLayerPoint AsyncPanZoomController::PanStart() const {
return ParentLayerPoint(mX.PanStart(), mY.PanStart());
}
const ParentLayerPoint AsyncPanZoomController::GetVelocityVector() const {
return ParentLayerPoint(mX.GetVelocity(), mY.GetVelocity());
}
void AsyncPanZoomController::SetVelocityVector(const ParentLayerPoint& aVelocityVector) {
mX.SetVelocity(aVelocityVector.x);
mY.SetVelocity(aVelocityVector.y);
}
void AsyncPanZoomController::HandlePanningWithTouchAction(double aAngle) {
// Handling of cross sliding will need to be added in this method after touch-action released
// enabled by default.
MOZ_ASSERT(GetCurrentTouchBlock());
if (GetCurrentTouchBlock()->TouchActionAllowsPanningXY()) {
if (mX.CanScrollNow() && mY.CanScrollNow()) {
if (IsCloseToHorizontal(aAngle, gfxPrefs::APZAxisLockAngle())) {
mY.SetAxisLocked(true);
SetState(PANNING_LOCKED_X);
} else if (IsCloseToVertical(aAngle, gfxPrefs::APZAxisLockAngle())) {
mX.SetAxisLocked(true);
SetState(PANNING_LOCKED_Y);
} else {
SetState(PANNING);
}
} else if (mX.CanScrollNow() || mY.CanScrollNow()) {
SetState(PANNING);
} else {
SetState(NOTHING);
}
} else if (GetCurrentTouchBlock()->TouchActionAllowsPanningX()) {
// Using bigger angle for panning to keep behavior consistent
// with IE.
if (IsCloseToHorizontal(aAngle, gfxPrefs::APZAllowedDirectPanAngle())) {
mY.SetAxisLocked(true);
SetState(PANNING_LOCKED_X);
mPanDirRestricted = true;
} else {
// Don't treat these touches as pan/zoom movements since 'touch-action' value
// requires it.
SetState(NOTHING);
}
} else if (GetCurrentTouchBlock()->TouchActionAllowsPanningY()) {
if (IsCloseToVertical(aAngle, gfxPrefs::APZAllowedDirectPanAngle())) {
mX.SetAxisLocked(true);
SetState(PANNING_LOCKED_Y);
mPanDirRestricted = true;
} else {
SetState(NOTHING);
}
} else {
SetState(NOTHING);
}
if (!IsInPanningState()) {
// If we didn't enter a panning state because touch-action disallowed it,
// make sure to clear any leftover velocity from the pre-threshold
// touchmoves.
mX.SetVelocity(0);
mY.SetVelocity(0);
}
}
void AsyncPanZoomController::HandlePanning(double aAngle) {
ReentrantMonitorAutoEnter lock(mMonitor);
MOZ_ASSERT(GetCurrentInputBlock());
RefPtr<const OverscrollHandoffChain> overscrollHandoffChain =
GetCurrentInputBlock()->GetOverscrollHandoffChain();
bool canScrollHorizontal = !mX.IsAxisLocked() &&
overscrollHandoffChain->CanScrollInDirection(this, Layer::HORIZONTAL);
bool canScrollVertical = !mY.IsAxisLocked() &&
overscrollHandoffChain->CanScrollInDirection(this, Layer::VERTICAL);
if (!canScrollHorizontal || !canScrollVertical) {
SetState(PANNING);
} else if (IsCloseToHorizontal(aAngle, gfxPrefs::APZAxisLockAngle())) {
mY.SetAxisLocked(true);
if (canScrollHorizontal) {
SetState(PANNING_LOCKED_X);
}
} else if (IsCloseToVertical(aAngle, gfxPrefs::APZAxisLockAngle())) {
mX.SetAxisLocked(true);
if (canScrollVertical) {
SetState(PANNING_LOCKED_Y);
}
} else {
SetState(PANNING);
}
}
void AsyncPanZoomController::HandlePanningUpdate(const ScreenPoint& aPanDistance) {
// If we're axis-locked, check if the user is trying to break the lock
if (GetAxisLockMode() == STICKY && !mPanDirRestricted) {
double angle = atan2(aPanDistance.y, aPanDistance.x); // range [-pi, pi]
angle = fabs(angle); // range [0, pi]
float breakThreshold = gfxPrefs::APZAxisBreakoutThreshold() * APZCTreeManager::GetDPI();
if (fabs(aPanDistance.x) > breakThreshold || fabs(aPanDistance.y) > breakThreshold) {
if (mState == PANNING_LOCKED_X) {
if (!IsCloseToHorizontal(angle, gfxPrefs::APZAxisBreakoutAngle())) {
mY.SetAxisLocked(false);
SetState(PANNING);
}
} else if (mState == PANNING_LOCKED_Y) {
if (!IsCloseToVertical(angle, gfxPrefs::APZAxisBreakoutAngle())) {
mX.SetAxisLocked(false);
SetState(PANNING);
}
}
}
}
}
nsEventStatus AsyncPanZoomController::StartPanning(const MultiTouchInput& aEvent) {
ReentrantMonitorAutoEnter lock(mMonitor);
ParentLayerPoint point = GetFirstTouchPoint(aEvent);
float dx = mX.PanDistance(point.x);
float dy = mY.PanDistance(point.y);
double angle = atan2(dy, dx); // range [-pi, pi]
angle = fabs(angle); // range [0, pi]
if (gfxPrefs::TouchActionEnabled()) {
HandlePanningWithTouchAction(angle);
} else {
if (GetAxisLockMode() == FREE) {
SetState(PANNING);
} else {
HandlePanning(angle);
}
}
if (IsInPanningState()) {
if (RefPtr<GeckoContentController> controller = GetGeckoContentController()) {
controller->NotifyAPZStateChange(GetGuid(), APZStateChange::eStartPanning);
}
return nsEventStatus_eConsumeNoDefault;
}
// Don't consume an event that didn't trigger a panning.
return nsEventStatus_eIgnore;
}
void AsyncPanZoomController::UpdateWithTouchAtDevicePoint(const MultiTouchInput& aEvent) {
ParentLayerPoint point = GetFirstTouchPoint(aEvent);
mX.UpdateWithTouchAtDevicePoint(point.x, 0, aEvent.mTime);
mY.UpdateWithTouchAtDevicePoint(point.y, 0, aEvent.mTime);
}
bool AsyncPanZoomController::AttemptScroll(ParentLayerPoint& aStartPoint,
ParentLayerPoint& aEndPoint,
OverscrollHandoffState& aOverscrollHandoffState) {
// "start - end" rather than "end - start" because e.g. moving your finger
// down (*positive* direction along y axis) causes the vertical scroll offset
// to *decrease* as the page follows your finger.
ParentLayerPoint displacement = aStartPoint - aEndPoint;
ParentLayerPoint overscroll; // will be used outside monitor block
// If the direction of panning is reversed within the same input block,
// a later event in the block could potentially scroll an APZC earlier
// in the handoff chain, than an earlier event in the block (because
// the earlier APZC was scrolled to its extent in the original direction).
// We want to disallow this.
bool scrollThisApzc = false;
if (InputBlockState* block = GetCurrentInputBlock()) {
scrollThisApzc = !block->GetScrolledApzc() || block->IsDownchainOfScrolledApzc(this);
}
if (scrollThisApzc) {
ReentrantMonitorAutoEnter lock(mMonitor);
ParentLayerPoint adjustedDisplacement;
bool forceVerticalOverscroll =
(aOverscrollHandoffState.mScrollSource == ScrollSource::Wheel &&
!mScrollMetadata.AllowVerticalScrollWithWheel());
bool yChanged = mY.AdjustDisplacement(displacement.y, adjustedDisplacement.y, overscroll.y,
forceVerticalOverscroll);
bool xChanged = mX.AdjustDisplacement(displacement.x, adjustedDisplacement.x, overscroll.x);
if (xChanged || yChanged) {
ScheduleComposite();
}
if (!IsZero(adjustedDisplacement)) {
ScrollBy(adjustedDisplacement / mFrameMetrics.GetZoom());
if (CancelableBlockState* block = GetCurrentInputBlock()) {
if (block->AsTouchBlock() && (block->GetScrolledApzc() != this)) {
RefPtr<GeckoContentController> controller = GetGeckoContentController();
if (controller) {
controller->SetScrollingRootContent(IsRootContent());
}
}
block->SetScrolledApzc(this);
}
ScheduleCompositeAndMaybeRepaint();
UpdateSharedCompositorFrameMetrics();
}
// Adjust the start point to reflect the consumed portion of the scroll.
aStartPoint = aEndPoint + overscroll;
} else {
overscroll = displacement;
}
// If we consumed the entire displacement as a normal scroll, great.
if (IsZero(overscroll)) {
return true;
}
if (AllowScrollHandoffInCurrentBlock()) {
// If there is overscroll, first try to hand it off to an APZC later
// in the handoff chain to consume (either as a normal scroll or as
// overscroll).
// Note: "+ overscroll" rather than "- overscroll" because "overscroll"
// is what's left of "displacement", and "displacement" is "start - end".
++aOverscrollHandoffState.mChainIndex;
CallDispatchScroll(aStartPoint, aEndPoint, aOverscrollHandoffState);
overscroll = aStartPoint - aEndPoint;
if (IsZero(overscroll)) {
return true;
}
}
// If there is no APZC later in the handoff chain that accepted the
// overscroll, try to accept it ourselves. We only accept it if we
// are pannable.
APZC_LOG("%p taking overscroll during panning\n", this);
OverscrollForPanning(overscroll, aOverscrollHandoffState.mPanDistance);
aStartPoint = aEndPoint + overscroll;
return IsZero(overscroll);
}
void AsyncPanZoomController::OverscrollForPanning(ParentLayerPoint& aOverscroll,
const ScreenPoint& aPanDistance) {
// Only allow entering overscroll along an axis if the pan distance along
// that axis is greater than the pan distance along the other axis by a
// configurable factor. If we are already overscrolled, don't check this.
if (!IsOverscrolled()) {
if (aPanDistance.x < gfxPrefs::APZMinPanDistanceRatio() * aPanDistance.y) {
aOverscroll.x = 0;
}
if (aPanDistance.y < gfxPrefs::APZMinPanDistanceRatio() * aPanDistance.x) {
aOverscroll.y = 0;
}
}
OverscrollBy(aOverscroll);
}
void AsyncPanZoomController::OverscrollBy(ParentLayerPoint& aOverscroll) {
if (!gfxPrefs::APZOverscrollEnabled()) {
return;
}
ReentrantMonitorAutoEnter lock(mMonitor);
// Do not go into overscroll in a direction in which we have no room to
// scroll to begin with.
bool xCanScroll = mX.CanScroll();
bool yCanScroll = mY.CanScroll();
bool xConsumed = FuzzyEqualsAdditive(aOverscroll.x, 0.0f, COORDINATE_EPSILON);
bool yConsumed = FuzzyEqualsAdditive(aOverscroll.y, 0.0f, COORDINATE_EPSILON);
bool shouldOverscrollX = xCanScroll && !xConsumed;
bool shouldOverscrollY = yCanScroll && !yConsumed;
mOverscrollEffect->ConsumeOverscroll(aOverscroll, shouldOverscrollX, shouldOverscrollY);
}
RefPtr<const OverscrollHandoffChain> AsyncPanZoomController::BuildOverscrollHandoffChain() {
if (APZCTreeManager* treeManagerLocal = GetApzcTreeManager()) {
return treeManagerLocal->BuildOverscrollHandoffChain(this);
}
// This APZC IsDestroyed(). To avoid callers having to special-case this
// scenario, just build a 1-element chain containing ourselves.
OverscrollHandoffChain* result = new OverscrollHandoffChain;
result->Add(this);
return result;
}
void AsyncPanZoomController::AcceptFling(FlingHandoffState& aHandoffState) {
ReentrantMonitorAutoEnter lock(mMonitor);
// We may have a pre-existing velocity for whatever reason (for example,
// a previously handed off fling). We don't want to clobber that.
APZC_LOG("%p accepting fling with velocity %s\n", this,
Stringify(aHandoffState.mVelocity).c_str());
if (mX.CanScroll()) {
mX.SetVelocity(mX.GetVelocity() + aHandoffState.mVelocity.x);
aHandoffState.mVelocity.x = 0;
}
if (mY.CanScroll()) {
mY.SetVelocity(mY.GetVelocity() + aHandoffState.mVelocity.y);
aHandoffState.mVelocity.y = 0;
}
// If there's a scroll snap point near the predicted fling destination,
// scroll there using a smooth scroll animation. Otherwise, start a
// fling animation.
ScrollSnapToDestination();
if (mState != SMOOTH_SCROLL) {
SetState(FLING);
FlingAnimation *fling = new FlingAnimation(*this,
GetPlatformSpecificState(),
aHandoffState.mChain,
aHandoffState.mIsHandoff,
aHandoffState.mScrolledApzc);
StartAnimation(fling);
}
}
bool AsyncPanZoomController::AttemptFling(FlingHandoffState& aHandoffState) {
// If we are pannable, take over the fling ourselves.
if (IsPannable()) {
AcceptFling(aHandoffState);
return true;
}
return false;
}
void AsyncPanZoomController::HandleFlingOverscroll(const ParentLayerPoint& aVelocity,
const RefPtr<const OverscrollHandoffChain>& aOverscrollHandoffChain,
const RefPtr<const AsyncPanZoomController>& aScrolledApzc) {
APZCTreeManager* treeManagerLocal = GetApzcTreeManager();
if (treeManagerLocal) {
FlingHandoffState handoffState{aVelocity,
aOverscrollHandoffChain,
true /* handoff */,
aScrolledApzc};
treeManagerLocal->DispatchFling(this, handoffState);
if (!IsZero(handoffState.mVelocity) && IsPannable() && gfxPrefs::APZOverscrollEnabled()) {
mOverscrollEffect->HandleFlingOverscroll(handoffState.mVelocity);
}
}
}
void AsyncPanZoomController::HandleSmoothScrollOverscroll(const ParentLayerPoint& aVelocity) {
// We must call BuildOverscrollHandoffChain from this deferred callback
// function in order to avoid a deadlock when acquiring the tree lock.
HandleFlingOverscroll(aVelocity, BuildOverscrollHandoffChain(), nullptr);
}
void AsyncPanZoomController::SmoothScrollTo(const CSSPoint& aDestination) {
if (mState == SMOOTH_SCROLL && mAnimation) {
APZC_LOG("%p updating destination on existing animation\n", this);
RefPtr<SmoothScrollAnimation> animation(
static_cast<SmoothScrollAnimation*>(mAnimation.get()));
animation->SetDestination(CSSPoint::ToAppUnits(aDestination));
} else {
CancelAnimation();
SetState(SMOOTH_SCROLL);
nsPoint initialPosition = CSSPoint::ToAppUnits(mFrameMetrics.GetScrollOffset());
// Cast velocity from ParentLayerPoints/ms to CSSPoints/ms then convert to
// appunits/second
nsPoint initialVelocity = CSSPoint::ToAppUnits(CSSPoint(mX.GetVelocity(),
mY.GetVelocity())) * 1000.0f;
nsPoint destination = CSSPoint::ToAppUnits(aDestination);
StartAnimation(new SmoothScrollAnimation(*this,
initialPosition, initialVelocity,
destination,
gfxPrefs::ScrollBehaviorSpringConstant(),
gfxPrefs::ScrollBehaviorDampingRatio()));
}
}
void AsyncPanZoomController::StartOverscrollAnimation(const ParentLayerPoint& aVelocity) {
SetState(OVERSCROLL_ANIMATION);
StartAnimation(new OverscrollAnimation(*this, aVelocity));
}
void AsyncPanZoomController::CallDispatchScroll(ParentLayerPoint& aStartPoint,
ParentLayerPoint& aEndPoint,
OverscrollHandoffState& aOverscrollHandoffState) {
// Make a local copy of the tree manager pointer and check if it's not
// null before calling DispatchScroll(). This is necessary because
// Destroy(), which nulls out mTreeManager, could be called concurrently.
APZCTreeManager* treeManagerLocal = GetApzcTreeManager();
if (!treeManagerLocal) {
return;
}
treeManagerLocal->DispatchScroll(this,
aStartPoint, aEndPoint,
aOverscrollHandoffState);
}
void AsyncPanZoomController::TrackTouch(const MultiTouchInput& aEvent) {
ParentLayerPoint prevTouchPoint(mX.GetPos(), mY.GetPos());
ParentLayerPoint touchPoint = GetFirstTouchPoint(aEvent);
ScreenPoint panDistance = ToScreenCoordinates(
ParentLayerPoint(mX.PanDistance(touchPoint.x),
mY.PanDistance(touchPoint.y)),
PanStart());
HandlePanningUpdate(panDistance);
UpdateWithTouchAtDevicePoint(aEvent);
if (prevTouchPoint != touchPoint) {
MOZ_ASSERT(GetCurrentTouchBlock());
OverscrollHandoffState handoffState(
*GetCurrentTouchBlock()->GetOverscrollHandoffChain(),
panDistance,
ScrollSource::Touch);
CallDispatchScroll(prevTouchPoint, touchPoint, handoffState);
}
}
ParentLayerPoint AsyncPanZoomController::GetFirstTouchPoint(const MultiTouchInput& aEvent) {
return ((SingleTouchData&)aEvent.mTouches[0]).mLocalScreenPoint;
}
void AsyncPanZoomController::StartAnimation(AsyncPanZoomAnimation* aAnimation)
{
ReentrantMonitorAutoEnter lock(mMonitor);
mAnimation = aAnimation;
mLastSampleTime = GetFrameTime();
ScheduleComposite();
}
void AsyncPanZoomController::CancelAnimation(CancelAnimationFlags aFlags) {
ReentrantMonitorAutoEnter lock(mMonitor);
APZC_LOG("%p running CancelAnimation in state %d\n", this, mState);
SetState(NOTHING);
mAnimation = nullptr;
// Since there is no animation in progress now the axes should
// have no velocity either. If we are dropping the velocity from a non-zero
// value we should trigger a repaint as the displayport margins are dependent
// on the velocity and the last repaint request might not have good margins
// any more.
bool repaint = !IsZero(GetVelocityVector());
mX.SetVelocity(0);
mY.SetVelocity(0);
mX.SetAxisLocked(false);
mY.SetAxisLocked(false);
// Setting the state to nothing and cancelling the animation can
// preempt normal mechanisms for relieving overscroll, so we need to clear
// overscroll here.
if (!(aFlags & ExcludeOverscroll) && IsOverscrolled()) {
ClearOverscroll();
repaint = true;
}
// Similar to relieving overscroll, we also need to snap to any snap points
// if appropriate.
if (aFlags & CancelAnimationFlags::ScrollSnap) {
ScrollSnap();
}
if (repaint) {
RequestContentRepaint();
ScheduleComposite();
UpdateSharedCompositorFrameMetrics();
}
}
void AsyncPanZoomController::ClearOverscroll() {
ReentrantMonitorAutoEnter lock(mMonitor);
mX.ClearOverscroll();
mY.ClearOverscroll();
}
void AsyncPanZoomController::SetCompositorController(CompositorController* aCompositorController)
{
mCompositorController = aCompositorController;
}
void AsyncPanZoomController::SetMetricsSharingController(MetricsSharingController* aMetricsSharingController)
{
mMetricsSharingController = aMetricsSharingController;
}
void AsyncPanZoomController::AdjustScrollForSurfaceShift(const ScreenPoint& aShift)
{
ReentrantMonitorAutoEnter lock(mMonitor);
CSSPoint adjustment =
ViewAs<ParentLayerPixel>(aShift, PixelCastJustification::ScreenIsParentLayerForRoot)
/ mFrameMetrics.GetZoom();
APZC_LOG("%p adjusting scroll position by %s for surface shift\n",
this, Stringify(adjustment).c_str());
CSSPoint scrollOffset = mFrameMetrics.GetScrollOffset();
scrollOffset.y = mY.ClampOriginToScrollableRect(scrollOffset.y + adjustment.y);
scrollOffset.x = mX.ClampOriginToScrollableRect(scrollOffset.x + adjustment.x);
mFrameMetrics.SetScrollOffset(scrollOffset);
ScheduleCompositeAndMaybeRepaint();
UpdateSharedCompositorFrameMetrics();
}
void AsyncPanZoomController::ScrollBy(const CSSPoint& aOffset) {
mFrameMetrics.ScrollBy(aOffset);
}
void AsyncPanZoomController::ScaleWithFocus(float aScale,
const CSSPoint& aFocus) {
mFrameMetrics.ZoomBy(aScale);
// We want to adjust the scroll offset such that the CSS point represented by aFocus remains
// at the same position on the screen before and after the change in zoom. The below code
// accomplishes this; see https://bugzilla.mozilla.org/show_bug.cgi?id=923431#c6 for an
// in-depth explanation of how.
mFrameMetrics.SetScrollOffset((mFrameMetrics.GetScrollOffset() + aFocus) - (aFocus / aScale));
}
/**
* Enlarges the displayport along both axes based on the velocity.
*/
static CSSSize
CalculateDisplayPortSize(const CSSSize& aCompositionSize,
const CSSPoint& aVelocity)
{
bool xIsStationarySpeed = fabsf(aVelocity.x) < gfxPrefs::APZMinSkateSpeed();
bool yIsStationarySpeed = fabsf(aVelocity.y) < gfxPrefs::APZMinSkateSpeed();
float xMultiplier = xIsStationarySpeed
? gfxPrefs::APZXStationarySizeMultiplier()
: gfxPrefs::APZXSkateSizeMultiplier();
float yMultiplier = yIsStationarySpeed
? gfxPrefs::APZYStationarySizeMultiplier()
: gfxPrefs::APZYSkateSizeMultiplier();
if (IsHighMemSystem() && !xIsStationarySpeed) {
xMultiplier += gfxPrefs::APZXSkateHighMemAdjust();
}
if (IsHighMemSystem() && !yIsStationarySpeed) {
yMultiplier += gfxPrefs::APZYSkateHighMemAdjust();
}
return aCompositionSize * CSSSize(xMultiplier, yMultiplier);
}
/**
* Ensures that the displayport is at least as large as the visible area
* inflated by the danger zone. If this is not the case then the
* "AboutToCheckerboard" function in TiledContentClient.cpp will return true
* even in the stable state.
*/
static CSSSize
ExpandDisplayPortToDangerZone(const CSSSize& aDisplayPortSize,
const FrameMetrics& aFrameMetrics)
{
CSSSize dangerZone(0.0f, 0.0f);
if (aFrameMetrics.LayersPixelsPerCSSPixel().xScale != 0 &&
aFrameMetrics.LayersPixelsPerCSSPixel().yScale != 0) {
dangerZone = LayerSize(
gfxPrefs::APZDangerZoneX(),
gfxPrefs::APZDangerZoneY()) / aFrameMetrics.LayersPixelsPerCSSPixel();
}
const CSSSize compositionSize = aFrameMetrics.CalculateBoundedCompositedSizeInCssPixels();
const float xSize = std::max(aDisplayPortSize.width,
compositionSize.width + (2 * dangerZone.width));
const float ySize = std::max(aDisplayPortSize.height,
compositionSize.height + (2 * dangerZone.height));
return CSSSize(xSize, ySize);
}
/**
* Attempts to redistribute any area in the displayport that would get clipped
* by the scrollable rect, or be inaccessible due to disabled scrolling, to the
* other axis, while maintaining total displayport area.
*/
static void
RedistributeDisplayPortExcess(CSSSize& aDisplayPortSize,
const CSSRect& aScrollableRect)
{
// As aDisplayPortSize.height * aDisplayPortSize.width does not change,
// we are just scaling by the ratio and its inverse.
if (aDisplayPortSize.height > aScrollableRect.height) {
aDisplayPortSize.width *= (aDisplayPortSize.height / aScrollableRect.height);
aDisplayPortSize.height = aScrollableRect.height;
} else if (aDisplayPortSize.width > aScrollableRect.width) {
aDisplayPortSize.height *= (aDisplayPortSize.width / aScrollableRect.width);
aDisplayPortSize.width = aScrollableRect.width;
}
}
/* static */
const ScreenMargin AsyncPanZoomController::CalculatePendingDisplayPort(
const FrameMetrics& aFrameMetrics,
const ParentLayerPoint& aVelocity)
{
if (aFrameMetrics.IsScrollInfoLayer()) {
// Don't compute margins. Since we can't asynchronously scroll this frame,
// we don't want to paint anything more than the composition bounds.
return ScreenMargin();
}
CSSSize compositionSize = aFrameMetrics.CalculateBoundedCompositedSizeInCssPixels();
CSSPoint velocity;
if (aFrameMetrics.GetZoom() != CSSToParentLayerScale2D(0, 0)) {
velocity = aVelocity / aFrameMetrics.GetZoom(); // avoid division by zero
}
CSSRect scrollableRect = aFrameMetrics.GetExpandedScrollableRect();
// Calculate the displayport size based on how fast we're moving along each axis.
CSSSize displayPortSize = CalculateDisplayPortSize(compositionSize, velocity);
displayPortSize = ExpandDisplayPortToDangerZone(displayPortSize, aFrameMetrics);
if (gfxPrefs::APZEnlargeDisplayPortWhenClipped()) {
RedistributeDisplayPortExcess(displayPortSize, scrollableRect);
}
// We calculate a "displayport" here which is relative to the scroll offset.
// Note that the scroll offset we have here in the APZ code may not be the
// same as the base rect that gets used on the layout side when the displayport
// margins are actually applied, so it is important to only consider the
// displayport as margins relative to a scroll offset rather than relative to
// something more unchanging like the scrollable rect origin.
// Center the displayport based on its expansion over the composition size.
CSSRect displayPort((compositionSize.width - displayPortSize.width) / 2.0f,
(compositionSize.height - displayPortSize.height) / 2.0f,
displayPortSize.width, displayPortSize.height);
// Offset the displayport, depending on how fast we're moving and the
// estimated time it takes to paint, to try to minimise checkerboarding.
float paintFactor = kDefaultEstimatedPaintDurationMs;
displayPort.MoveBy(velocity * paintFactor * gfxPrefs::APZVelocityBias());
APZC_LOG_FM(aFrameMetrics,
"Calculated displayport as (%f %f %f %f) from velocity %s paint time %f metrics",
displayPort.x, displayPort.y, displayPort.width, displayPort.height,
ToString(aVelocity).c_str(), paintFactor);
CSSMargin cssMargins;
cssMargins.left = -displayPort.x;
cssMargins.top = -displayPort.y;
cssMargins.right = displayPort.width - compositionSize.width - cssMargins.left;
cssMargins.bottom = displayPort.height - compositionSize.height - cssMargins.top;
return cssMargins * aFrameMetrics.DisplayportPixelsPerCSSPixel();
}
void AsyncPanZoomController::ScheduleComposite() {
if (mCompositorController) {
mCompositorController->ScheduleRenderOnCompositorThread();
}
}
void AsyncPanZoomController::ScheduleCompositeAndMaybeRepaint() {
ScheduleComposite();
RequestContentRepaint();
}
void AsyncPanZoomController::FlushRepaintForOverscrollHandoff() {
ReentrantMonitorAutoEnter lock(mMonitor);
RequestContentRepaint();
UpdateSharedCompositorFrameMetrics();
}
void AsyncPanZoomController::FlushRepaintForNewInputBlock() {
APZC_LOG("%p flushing repaint for new input block\n", this);
ReentrantMonitorAutoEnter lock(mMonitor);
RequestContentRepaint();
UpdateSharedCompositorFrameMetrics();
}
bool AsyncPanZoomController::SnapBackIfOverscrolled() {
ReentrantMonitorAutoEnter lock(mMonitor);
// It's possible that we're already in the middle of an overscroll
// animation - if so, don't start a new one.
if (IsOverscrolled() && mState != OVERSCROLL_ANIMATION) {
APZC_LOG("%p is overscrolled, starting snap-back\n", this);
StartOverscrollAnimation(ParentLayerPoint(0, 0));
return true;
}
// If we don't kick off an overscroll animation, we still need to ask the
// main thread to snap to any nearby snap points, assuming we haven't already
// done so when we started this fling
if (mState != FLING) {
ScrollSnap();
}
return false;
}
bool AsyncPanZoomController::IsFlingingFast() const {
ReentrantMonitorAutoEnter lock(mMonitor);
if (mState == FLING &&
GetVelocityVector().Length() > gfxPrefs::APZFlingStopOnTapThreshold()) {
APZC_LOG("%p is moving fast\n", this);
return true;
}
return false;
}
bool AsyncPanZoomController::IsPannable() const {
ReentrantMonitorAutoEnter lock(mMonitor);
return mX.CanScroll() || mY.CanScroll();
}
int32_t AsyncPanZoomController::GetLastTouchIdentifier() const {
RefPtr<GestureEventListener> listener = GetGestureEventListener();
return listener ? listener->GetLastTouchIdentifier() : -1;
}
void AsyncPanZoomController::RequestContentRepaint(bool aUserAction) {
// Reinvoke this method on the repaint thread if it's not there already. It's
// important to do this before the call to CalculatePendingDisplayPort, so
// that CalculatePendingDisplayPort uses the most recent available version of
// mFrameMetrics, just before the paint request is dispatched to content.
RefPtr<GeckoContentController> controller = GetGeckoContentController();
if (!controller) {
return;
}
if (!controller->IsRepaintThread()) {
// use the local variable to resolve the function overload.
auto func = static_cast<void (AsyncPanZoomController::*)(bool)>
(&AsyncPanZoomController::RequestContentRepaint);
controller->DispatchToRepaintThread(NewRunnableMethod<bool>(this, func, aUserAction));
return;
}
MOZ_ASSERT(controller->IsRepaintThread());
ReentrantMonitorAutoEnter lock(mMonitor);
ParentLayerPoint velocity = GetVelocityVector();
mFrameMetrics.SetDisplayPortMargins(CalculatePendingDisplayPort(mFrameMetrics, velocity));
mFrameMetrics.SetUseDisplayPortMargins(true);
mFrameMetrics.SetPaintRequestTime(TimeStamp::Now());
mFrameMetrics.SetRepaintDrivenByUserAction(aUserAction);
RequestContentRepaint(mFrameMetrics, velocity);
}
/*static*/ CSSRect
GetDisplayPortRect(const FrameMetrics& aFrameMetrics)
{
// This computation is based on what happens in CalculatePendingDisplayPort. If that
// changes then this might need to change too
CSSRect baseRect(aFrameMetrics.GetScrollOffset(),
aFrameMetrics.CalculateBoundedCompositedSizeInCssPixels());
baseRect.Inflate(aFrameMetrics.GetDisplayPortMargins() / aFrameMetrics.DisplayportPixelsPerCSSPixel());
return baseRect;
}
void
AsyncPanZoomController::RequestContentRepaint(const FrameMetrics& aFrameMetrics,
const ParentLayerPoint& aVelocity)
{
RefPtr<GeckoContentController> controller = GetGeckoContentController();
if (!controller) {
return;
}
MOZ_ASSERT(controller->IsRepaintThread());
// If we're trying to paint what we already think is painted, discard this
// request since it's a pointless paint.
ScreenMargin marginDelta = (mLastPaintRequestMetrics.GetDisplayPortMargins()
- aFrameMetrics.GetDisplayPortMargins());
if (fabsf(marginDelta.left) < EPSILON &&
fabsf(marginDelta.top) < EPSILON &&
fabsf(marginDelta.right) < EPSILON &&
fabsf(marginDelta.bottom) < EPSILON &&
fabsf(mLastPaintRequestMetrics.GetScrollOffset().x -
aFrameMetrics.GetScrollOffset().x) < EPSILON &&
fabsf(mLastPaintRequestMetrics.GetScrollOffset().y -
aFrameMetrics.GetScrollOffset().y) < EPSILON &&
aFrameMetrics.GetPresShellResolution() == mLastPaintRequestMetrics.GetPresShellResolution() &&
aFrameMetrics.GetZoom() == mLastPaintRequestMetrics.GetZoom() &&
fabsf(aFrameMetrics.GetViewport().width -
mLastPaintRequestMetrics.GetViewport().width) < EPSILON &&
fabsf(aFrameMetrics.GetViewport().height -
mLastPaintRequestMetrics.GetViewport().height) < EPSILON &&
aFrameMetrics.GetScrollGeneration() ==
mLastPaintRequestMetrics.GetScrollGeneration() &&
aFrameMetrics.GetScrollUpdateType() ==
mLastPaintRequestMetrics.GetScrollUpdateType()) {
return;
}
APZC_LOG_FM(aFrameMetrics, "%p requesting content repaint", this);
{ // scope lock
MutexAutoLock lock(mCheckerboardEventLock);
if (mCheckerboardEvent && mCheckerboardEvent->IsRecordingTrace()) {
std::stringstream info;
info << " velocity " << aVelocity;
std::string str = info.str();
mCheckerboardEvent->UpdateRendertraceProperty(
CheckerboardEvent::RequestedDisplayPort, GetDisplayPortRect(aFrameMetrics),
str);
}
}
MOZ_ASSERT(aFrameMetrics.GetScrollUpdateType() == FrameMetrics::eNone ||
aFrameMetrics.GetScrollUpdateType() == FrameMetrics::eUserAction);
controller->RequestContentRepaint(aFrameMetrics);
mExpectedGeckoMetrics = aFrameMetrics;
mLastPaintRequestMetrics = aFrameMetrics;
}
bool AsyncPanZoomController::UpdateAnimation(const TimeStamp& aSampleTime,
nsTArray<RefPtr<Runnable>>* aOutDeferredTasks)
{
APZThreadUtils::AssertOnCompositorThread();
// This function may get called multiple with the same sample time, because
// there may be multiple layers with this APZC, and each layer invokes this
// function during composition. However we only want to do one animation step
// per composition so we need to deduplicate these calls first.
if (mLastSampleTime == aSampleTime) {
return false;
}
TimeDuration sampleTimeDelta = aSampleTime - mLastSampleTime;
mLastSampleTime = aSampleTime;
if (mAnimation) {
bool continueAnimation = mAnimation->Sample(mFrameMetrics, sampleTimeDelta);
bool wantsRepaints = mAnimation->WantsRepaints();
*aOutDeferredTasks = mAnimation->TakeDeferredTasks();
if (!continueAnimation) {
mAnimation = nullptr;
SetState(NOTHING);
}
// Request a repaint at the end of the animation in case something such as a
// call to NotifyLayersUpdated was invoked during the animation and Gecko's
// current state is some intermediate point of the animation.
if (!continueAnimation || wantsRepaints) {
RequestContentRepaint();
}
UpdateSharedCompositorFrameMetrics();
return true;
}
return false;
}
AsyncTransformComponentMatrix
AsyncPanZoomController::GetOverscrollTransform(AsyncMode aMode) const
{
ReentrantMonitorAutoEnter lock(mMonitor);
if (aMode == RESPECT_FORCE_DISABLE && mScrollMetadata.IsApzForceDisabled()) {
return AsyncTransformComponentMatrix();
}
if (!IsOverscrolled()) {
return AsyncTransformComponentMatrix();
}
// The overscroll effect is a uniform stretch along the overscrolled axis,
// with the edge of the content where we have reached the end of the
// scrollable area pinned into place.
// The kStretchFactor parameter determines how much overscroll can stretch the
// content.
const float kStretchFactor = gfxPrefs::APZOverscrollStretchFactor();
// Compute the amount of the stretch along each axis. The stretch is
// proportional to the amount by which we are overscrolled along that axis.
ParentLayerSize compositionSize(mX.GetCompositionLength(), mY.GetCompositionLength());
float scaleX = 1 + kStretchFactor * fabsf(mX.GetOverscroll()) / mX.GetCompositionLength();
float scaleY = 1 + kStretchFactor * fabsf(mY.GetOverscroll()) / mY.GetCompositionLength();
// The scale is applied relative to the origin of the composition bounds, i.e.
// it keeps the top-left corner of the content in place. This is fine if we
// are overscrolling at the top or on the left, but if we are overscrolling
// at the bottom or on the right, we want the bottom or right edge of the
// content to stay in place instead, so we add a translation to compensate.
ParentLayerPoint translation;
bool overscrolledOnRight = mX.GetOverscroll() > 0;
if (overscrolledOnRight) {
ParentLayerCoord overscrolledCompositionWidth = scaleX * compositionSize.width;
ParentLayerCoord extraCompositionWidth = overscrolledCompositionWidth - compositionSize.width;
translation.x = -extraCompositionWidth;
}
bool overscrolledAtBottom = mY.GetOverscroll() > 0;
if (overscrolledAtBottom) {
ParentLayerCoord overscrolledCompositionHeight = scaleY * compositionSize.height;
ParentLayerCoord extraCompositionHeight = overscrolledCompositionHeight - compositionSize.height;
translation.y = -extraCompositionHeight;
}
// Combine the transformations into a matrix.
return AsyncTransformComponentMatrix::Scaling(scaleX, scaleY, 1)
.PostTranslate(translation.x, translation.y, 0);
}
bool AsyncPanZoomController::AdvanceAnimations(const TimeStamp& aSampleTime)
{
APZThreadUtils::AssertOnCompositorThread();
// Don't send any state-change notifications until the end of the function,
// because we may go through some intermediate states while we finish
// animations and start new ones.
StateChangeNotificationBlocker blocker(this);
// The eventual return value of this function. The compositor needs to know
// whether or not to advance by a frame as soon as it can. For example, if a
// fling is happening, it has to keep compositing so that the animation is
// smooth. If an animation frame is requested, it is the compositor's
// responsibility to schedule a composite.
mAsyncTransformAppliedToContent = false;
bool requestAnimationFrame = false;
nsTArray<RefPtr<Runnable>> deferredTasks;
{
ReentrantMonitorAutoEnter lock(mMonitor);
requestAnimationFrame = UpdateAnimation(aSampleTime, &deferredTasks);
{ // scope lock
MutexAutoLock lock(mCheckerboardEventLock);
if (mCheckerboardEvent) {
mCheckerboardEvent->UpdateRendertraceProperty(
CheckerboardEvent::UserVisible,
CSSRect(mFrameMetrics.GetScrollOffset(),
mFrameMetrics.CalculateCompositedSizeInCssPixels()));
}
}
}
// Execute any deferred tasks queued up by mAnimation's Sample() (called by
// UpdateAnimation()). This needs to be done after the monitor is released
// since the tasks are allowed to call APZCTreeManager methods which can grab
// the tree lock.
for (uint32_t i = 0; i < deferredTasks.Length(); ++i) {
deferredTasks[i]->Run();
deferredTasks[i] = nullptr;
}
// One of the deferred tasks may have started a new animation. In this case,
// we want to ask the compositor to schedule a new composite.
requestAnimationFrame |= (mAnimation != nullptr);
return requestAnimationFrame;
}
ParentLayerPoint
AsyncPanZoomController::GetCurrentAsyncScrollOffset(AsyncMode aMode) const
{
ReentrantMonitorAutoEnter lock(mMonitor);
if (aMode == RESPECT_FORCE_DISABLE && mScrollMetadata.IsApzForceDisabled()) {
return mLastContentPaintMetrics.GetScrollOffset() * mLastContentPaintMetrics.GetZoom();
}
return (mFrameMetrics.GetScrollOffset() + mTestAsyncScrollOffset)
* mFrameMetrics.GetZoom() * mTestAsyncZoom.scale;
}
AsyncTransform
AsyncPanZoomController::GetCurrentAsyncTransform(AsyncMode aMode) const
{
ReentrantMonitorAutoEnter lock(mMonitor);
if (aMode == RESPECT_FORCE_DISABLE && mScrollMetadata.IsApzForceDisabled()) {
return AsyncTransform();
}
CSSPoint lastPaintScrollOffset;
if (mLastContentPaintMetrics.IsScrollable()) {
lastPaintScrollOffset = mLastContentPaintMetrics.GetScrollOffset();
}
CSSPoint currentScrollOffset = mFrameMetrics.GetScrollOffset() +
mTestAsyncScrollOffset;
// If checkerboarding has been disallowed, clamp the scroll position to stay
// within rendered content.
if (!gfxPrefs::APZAllowCheckerboarding() &&
!mLastContentPaintMetrics.GetDisplayPort().IsEmpty()) {
CSSSize compositedSize = mLastContentPaintMetrics.CalculateCompositedSizeInCssPixels();
CSSPoint maxScrollOffset = lastPaintScrollOffset +
CSSPoint(mLastContentPaintMetrics.GetDisplayPort().XMost() - compositedSize.width,
mLastContentPaintMetrics.GetDisplayPort().YMost() - compositedSize.height);
CSSPoint minScrollOffset = lastPaintScrollOffset + mLastContentPaintMetrics.GetDisplayPort().TopLeft();
if (minScrollOffset.x < maxScrollOffset.x) {
currentScrollOffset.x = clamped(currentScrollOffset.x, minScrollOffset.x, maxScrollOffset.x);
}
if (minScrollOffset.y < maxScrollOffset.y) {
currentScrollOffset.y = clamped(currentScrollOffset.y, minScrollOffset.y, maxScrollOffset.y);
}
}
ParentLayerPoint translation = (currentScrollOffset - lastPaintScrollOffset)
* mFrameMetrics.GetZoom() * mTestAsyncZoom.scale;
return AsyncTransform(
LayerToParentLayerScale(mFrameMetrics.GetAsyncZoom().scale * mTestAsyncZoom.scale),
-translation);
}
AsyncTransformComponentMatrix
AsyncPanZoomController::GetCurrentAsyncTransformWithOverscroll(AsyncMode aMode) const
{
return AsyncTransformComponentMatrix(GetCurrentAsyncTransform(aMode))
* GetOverscrollTransform(aMode);
}
Matrix4x4 AsyncPanZoomController::GetTransformToLastDispatchedPaint() const {
ReentrantMonitorAutoEnter lock(mMonitor);
LayerPoint scrollChange =
(mLastContentPaintMetrics.GetScrollOffset() - mExpectedGeckoMetrics.GetScrollOffset())
* mLastContentPaintMetrics.GetDevPixelsPerCSSPixel()
* mLastContentPaintMetrics.GetCumulativeResolution();
// We're interested in the async zoom change. Factor out the content scale
// that may change when dragging the window to a monitor with a different
// content scale.
LayoutDeviceToParentLayerScale2D lastContentZoom =
mLastContentPaintMetrics.GetZoom() / mLastContentPaintMetrics.GetDevPixelsPerCSSPixel();
LayoutDeviceToParentLayerScale2D lastDispatchedZoom =
mExpectedGeckoMetrics.GetZoom() / mExpectedGeckoMetrics.GetDevPixelsPerCSSPixel();
gfxSize zoomChange = lastContentZoom / lastDispatchedZoom;
return Matrix4x4::Translation(scrollChange.x, scrollChange.y, 0).
PostScale(zoomChange.width, zoomChange.height, 1);
}
uint32_t
AsyncPanZoomController::GetCheckerboardMagnitude() const
{
ReentrantMonitorAutoEnter lock(mMonitor);
CSSPoint currentScrollOffset = mFrameMetrics.GetScrollOffset() + mTestAsyncScrollOffset;
CSSRect painted = mLastContentPaintMetrics.GetDisplayPort() + mLastContentPaintMetrics.GetScrollOffset();
CSSRect visible = CSSRect(currentScrollOffset, mFrameMetrics.CalculateCompositedSizeInCssPixels());
CSSIntRegion checkerboard;
// Round so as to minimize checkerboarding; if we're only showing fractional
// pixels of checkerboarding it's not really worth counting
checkerboard.Sub(RoundedIn(visible), RoundedOut(painted));
return checkerboard.Area();
}
void
AsyncPanZoomController::ReportCheckerboard(const TimeStamp& aSampleTime)
{
if (mLastCheckerboardReport == aSampleTime) {
// This function will get called multiple times for each APZC on a single
// composite (once for each layer it is attached to). Only report the
// checkerboard once per composite though.
return;
}
mLastCheckerboardReport = aSampleTime;
bool recordTrace = gfxPrefs::APZRecordCheckerboarding();
uint32_t magnitude = GetCheckerboardMagnitude();
MutexAutoLock lock(mCheckerboardEventLock);
if (!mCheckerboardEvent && recordTrace) {
mCheckerboardEvent = MakeUnique<CheckerboardEvent>(recordTrace);
}
mPotentialCheckerboardTracker.InTransform(IsTransformingState(mState));
if (magnitude) {
mPotentialCheckerboardTracker.CheckerboardSeen();
}
UpdateCheckerboardEvent(lock, magnitude);
}
void
AsyncPanZoomController::UpdateCheckerboardEvent(const MutexAutoLock& aProofOfLock,
uint32_t aMagnitude)
{
if (mCheckerboardEvent && mCheckerboardEvent->RecordFrameInfo(aMagnitude)) {
// This checkerboard event is done.
mPotentialCheckerboardTracker.CheckerboardDone();
if (gfxPrefs::APZRecordCheckerboarding()) {
// if the pref is enabled, also send it to the storage class. it may be
// chosen for public display on about:checkerboard, the hall of fame for
// checkerboard events.
uint32_t severity = mCheckerboardEvent->GetSeverity();
std::string log = mCheckerboardEvent->GetLog();
CheckerboardEventStorage::Report(severity, log);
}
mCheckerboardEvent = nullptr;
}
}
void
AsyncPanZoomController::FlushActiveCheckerboardReport()
{
MutexAutoLock lock(mCheckerboardEventLock);
// Pretend like we got a frame with 0 pixels checkerboarded. This will
// terminate the checkerboard event and flush it out
UpdateCheckerboardEvent(lock, 0);
}
bool AsyncPanZoomController::IsCurrentlyCheckerboarding() const {
ReentrantMonitorAutoEnter lock(mMonitor);
if (!gfxPrefs::APZAllowCheckerboarding() || mScrollMetadata.IsApzForceDisabled()) {
return false;
}
CSSPoint currentScrollOffset = mFrameMetrics.GetScrollOffset() + mTestAsyncScrollOffset;
CSSRect painted = mLastContentPaintMetrics.GetDisplayPort() + mLastContentPaintMetrics.GetScrollOffset();
painted.Inflate(CSSMargin::FromAppUnits(nsMargin(1, 1, 1, 1))); // fuzz for rounding error
CSSRect visible = CSSRect(currentScrollOffset, mFrameMetrics.CalculateCompositedSizeInCssPixels());
if (painted.Contains(visible)) {
return false;
}
APZC_LOG_FM(mFrameMetrics, "%p is currently checkerboarding (painted %s visble %s)",
this, Stringify(painted).c_str(), Stringify(visible).c_str());
return true;
}
void AsyncPanZoomController::NotifyLayersUpdated(const ScrollMetadata& aScrollMetadata,
bool aIsFirstPaint,
bool aThisLayerTreeUpdated)
{
APZThreadUtils::AssertOnCompositorThread();
ReentrantMonitorAutoEnter lock(mMonitor);
bool isDefault = mScrollMetadata.IsDefault();
const FrameMetrics& aLayerMetrics = aScrollMetadata.GetMetrics();
if ((aScrollMetadata == mLastContentPaintMetadata) && !isDefault) {
// No new information here, skip it.
APZC_LOG("%p NotifyLayersUpdated short-circuit\n", this);
return;
}
// If the mFrameMetrics scroll offset is different from the last scroll offset
// that the main-thread sent us, then we know that the user has been doing
// something that triggers a scroll. This check is the APZ equivalent of the
// check on the main-thread at
// https://hg.mozilla.org/mozilla-central/file/97a52326b06a/layout/generic/nsGfxScrollFrame.cpp#l4050
// There is code below (the use site of userScrolled) that prevents a restored-
// scroll-position update from overwriting a user scroll, again equivalent to
// how the main thread code does the same thing.
CSSPoint lastScrollOffset = mLastContentPaintMetadata.GetMetrics().GetScrollOffset();
bool userScrolled =
!FuzzyEqualsAdditive(mFrameMetrics.GetScrollOffset().x, lastScrollOffset.x) ||
!FuzzyEqualsAdditive(mFrameMetrics.GetScrollOffset().y, lastScrollOffset.y);
if (aLayerMetrics.GetScrollUpdateType() != FrameMetrics::ScrollOffsetUpdateType::ePending) {
mLastContentPaintMetadata = aScrollMetadata;
}
mScrollMetadata.SetScrollParentId(aScrollMetadata.GetScrollParentId());
APZC_LOG_FM(aLayerMetrics, "%p got a NotifyLayersUpdated with aIsFirstPaint=%d, aThisLayerTreeUpdated=%d",
this, aIsFirstPaint, aThisLayerTreeUpdated);
{ // scope lock
MutexAutoLock lock(mCheckerboardEventLock);
if (mCheckerboardEvent && mCheckerboardEvent->IsRecordingTrace()) {
std::string str;
if (aThisLayerTreeUpdated) {
if (!aLayerMetrics.GetPaintRequestTime().IsNull()) {
// Note that we might get the paint request time as non-null, but with
// aThisLayerTreeUpdated false. That can happen if we get a layer transaction
// from a different process right after we get the layer transaction with
// aThisLayerTreeUpdated == true. In this case we want to ignore the
// paint request time because it was already dumped in the previous layer
// transaction.
TimeDuration paintTime = TimeStamp::Now() - aLayerMetrics.GetPaintRequestTime();
std::stringstream info;
info << " painttime " << paintTime.ToMilliseconds();
str = info.str();
} else {
// This might be indicative of a wasted paint particularly if it happens
// during a checkerboard event.
str = " (this layertree updated)";
}
}
mCheckerboardEvent->UpdateRendertraceProperty(
CheckerboardEvent::Page, aLayerMetrics.GetScrollableRect());
mCheckerboardEvent->UpdateRendertraceProperty(
CheckerboardEvent::PaintedDisplayPort,
aLayerMetrics.GetDisplayPort() + aLayerMetrics.GetScrollOffset(),
str);
if (!aLayerMetrics.GetCriticalDisplayPort().IsEmpty()) {
mCheckerboardEvent->UpdateRendertraceProperty(
CheckerboardEvent::PaintedCriticalDisplayPort,
aLayerMetrics.GetCriticalDisplayPort() + aLayerMetrics.GetScrollOffset());
}
}
}
bool needContentRepaint = false;
bool viewportUpdated = false;
if (FuzzyEqualsAdditive(aLayerMetrics.GetCompositionBounds().width, mFrameMetrics.GetCompositionBounds().width) &&
FuzzyEqualsAdditive(aLayerMetrics.GetCompositionBounds().height, mFrameMetrics.GetCompositionBounds().height)) {
// Remote content has sync'd up to the composition geometry
// change, so we can accept the viewport it's calculated.
if (mFrameMetrics.GetViewport().width != aLayerMetrics.GetViewport().width ||
mFrameMetrics.GetViewport().height != aLayerMetrics.GetViewport().height) {
needContentRepaint = true;
viewportUpdated = true;
}
mFrameMetrics.SetViewport(aLayerMetrics.GetViewport());
}
// If the layers update was not triggered by our own repaint request, then
// we want to take the new scroll offset. Check the scroll generation as well
// to filter duplicate calls to NotifyLayersUpdated with the same scroll offset
// update message.
bool scrollOffsetUpdated = aLayerMetrics.GetScrollOffsetUpdated()
&& (aLayerMetrics.GetScrollGeneration() != mFrameMetrics.GetScrollGeneration());
if (scrollOffsetUpdated && userScrolled &&
aLayerMetrics.GetScrollUpdateType() == FrameMetrics::ScrollOffsetUpdateType::eRestore) {
APZC_LOG("%p dropping scroll update of type eRestore because of user scroll\n", this);
scrollOffsetUpdated = false;
}
bool smoothScrollRequested = aLayerMetrics.GetDoSmoothScroll()
&& (aLayerMetrics.GetScrollGeneration() != mFrameMetrics.GetScrollGeneration());
// TODO if we're in a drag and scrollOffsetUpdated is set then we want to
// ignore it
if ((aIsFirstPaint && aThisLayerTreeUpdated) || isDefault) {
// Initialize our internal state to something sane when the content
// that was just painted is something we knew nothing about previously
CancelAnimation();
mScrollMetadata = aScrollMetadata;
mExpectedGeckoMetrics = aLayerMetrics;
ShareCompositorFrameMetrics();
if (mFrameMetrics.GetDisplayPortMargins() != ScreenMargin()) {
// A non-zero display port margin here indicates a displayport has
// been set by a previous APZC for the content at this guid. The
// scrollable rect may have changed since then, making the margins
// wrong, so we need to calculate a new display port.
APZC_LOG("%p detected non-empty margins which probably need updating\n", this);
needContentRepaint = true;
}
} else {
// If we're not taking the aLayerMetrics wholesale we still need to pull
// in some things into our local mFrameMetrics because these things are
// determined by Gecko and our copy in mFrameMetrics may be stale.
if (FuzzyEqualsAdditive(mFrameMetrics.GetCompositionBounds().width, aLayerMetrics.GetCompositionBounds().width) &&
mFrameMetrics.GetDevPixelsPerCSSPixel() == aLayerMetrics.GetDevPixelsPerCSSPixel() &&
!viewportUpdated) {
// Any change to the pres shell resolution was requested by APZ and is
// already included in our zoom; however, other components of the
// cumulative resolution (a parent document's pres-shell resolution, or
// the css-driven resolution) may have changed, and we need to update
// our zoom to reflect that. Note that we can't just take
// aLayerMetrics.mZoom because the APZ may have additional async zoom
// since the repaint request.
gfxSize totalResolutionChange = aLayerMetrics.GetCumulativeResolution()
/ mFrameMetrics.GetCumulativeResolution();
float presShellResolutionChange = aLayerMetrics.GetPresShellResolution()
/ mFrameMetrics.GetPresShellResolution();
if (presShellResolutionChange != 1.0f) {
needContentRepaint = true;
}
mFrameMetrics.ZoomBy(totalResolutionChange / presShellResolutionChange);
} else {
// Take the new zoom as either device scale or composition width or
// viewport size got changed (e.g. due to orientation change, or content
// changing the meta-viewport tag).
mFrameMetrics.SetZoom(aLayerMetrics.GetZoom());
mFrameMetrics.SetDevPixelsPerCSSPixel(aLayerMetrics.GetDevPixelsPerCSSPixel());
}
if (!mFrameMetrics.GetScrollableRect().IsEqualEdges(aLayerMetrics.GetScrollableRect())) {
mFrameMetrics.SetScrollableRect(aLayerMetrics.GetScrollableRect());
needContentRepaint = true;
}
mFrameMetrics.SetCompositionBounds(aLayerMetrics.GetCompositionBounds());
mFrameMetrics.SetRootCompositionSize(aLayerMetrics.GetRootCompositionSize());
mFrameMetrics.SetPresShellResolution(aLayerMetrics.GetPresShellResolution());
mFrameMetrics.SetCumulativeResolution(aLayerMetrics.GetCumulativeResolution());
mScrollMetadata.SetHasScrollgrab(aScrollMetadata.GetHasScrollgrab());
mScrollMetadata.SetLineScrollAmount(aScrollMetadata.GetLineScrollAmount());
mScrollMetadata.SetPageScrollAmount(aScrollMetadata.GetPageScrollAmount());
mScrollMetadata.SetSnapInfo(ScrollSnapInfo(aScrollMetadata.GetSnapInfo()));
// The scroll clip can differ between layers associated a given scroll frame,
// so APZC (which keeps a single copy of ScrollMetadata per scroll frame)
// has no business using it.
mScrollMetadata.SetScrollClip(Nothing());
mScrollMetadata.SetIsLayersIdRoot(aScrollMetadata.IsLayersIdRoot());
mScrollMetadata.SetUsesContainerScrolling(aScrollMetadata.UsesContainerScrolling());
mFrameMetrics.SetIsScrollInfoLayer(aLayerMetrics.IsScrollInfoLayer());
mScrollMetadata.SetForceDisableApz(aScrollMetadata.IsApzForceDisabled());
if (scrollOffsetUpdated) {
APZC_LOG("%p updating scroll offset from %s to %s\n", this,
ToString(mFrameMetrics.GetScrollOffset()).c_str(),
ToString(aLayerMetrics.GetScrollOffset()).c_str());
// Send an acknowledgement with the new scroll generation so that any
// repaint requests later in this function go through.
// Because of the scroll generation update, any inflight paint requests are
// going to be ignored by layout, and so mExpectedGeckoMetrics
// becomes incorrect for the purposes of calculating the LD transform. To
// correct this we need to update mExpectedGeckoMetrics to be the
// last thing we know was painted by Gecko.
mFrameMetrics.CopyScrollInfoFrom(aLayerMetrics);
mExpectedGeckoMetrics = aLayerMetrics;
// Cancel the animation (which might also trigger a repaint request)
// after we update the scroll offset above. Otherwise we can be left
// in a state where things are out of sync.
CancelAnimation();
// Since the scroll offset has changed, we need to recompute the
// displayport margins and send them to layout. Otherwise there might be
// scenarios where for example we scroll from the top of a page (where the
// top displayport margin is zero) to the bottom of a page, which will
// result in a displayport that doesn't extend upwards at all.
// Note that even if the CancelAnimation call above requested a repaint
// this is fine because we already have repaint request deduplication.
needContentRepaint = true;
}
}
if (smoothScrollRequested) {
// A smooth scroll has been requested for animation on the compositor
// thread. This flag will be reset by the main thread when it receives
// the scroll update acknowledgement.
APZC_LOG("%p smooth scrolling from %s to %s in state %d\n", this,
Stringify(mFrameMetrics.GetScrollOffset()).c_str(),
Stringify(aLayerMetrics.GetSmoothScrollOffset()).c_str(),
mState);
// See comment on the similar code in the |if (scrollOffsetUpdated)| block
// above.
mFrameMetrics.CopySmoothScrollInfoFrom(aLayerMetrics);
needContentRepaint = true;
mExpectedGeckoMetrics = aLayerMetrics;
SmoothScrollTo(mFrameMetrics.GetSmoothScrollOffset());
}
if (needContentRepaint) {
// This repaint request is not driven by a user action on the APZ side
RequestContentRepaint(false);
}
UpdateSharedCompositorFrameMetrics();
}
const FrameMetrics& AsyncPanZoomController::GetFrameMetrics() const {
mMonitor.AssertCurrentThreadIn();
return mFrameMetrics;
}
APZCTreeManager* AsyncPanZoomController::GetApzcTreeManager() const {
mMonitor.AssertNotCurrentThreadIn();
return mTreeManager;
}
void AsyncPanZoomController::ZoomToRect(CSSRect aRect, const uint32_t aFlags) {
if (!aRect.IsFinite()) {
NS_WARNING("ZoomToRect got called with a non-finite rect; ignoring...");
return;
} else if (aRect.IsEmpty() && (aFlags & DISABLE_ZOOM_OUT)) {
// Double-tap-to-zooming uses an empty rect to mean "zoom out".
// If zooming out is disabled, an empty rect is nonsensical
// and will produce undesirable scrolling.
NS_WARNING("ZoomToRect got called with an empty rect and zoom out disabled; ignoring...");
return;
}
// Only the root APZC is zoomable, and the root APZC is not allowed to have
// different x and y scales. If it did, the calculations in this function
// would have to be adjusted (as e.g. it would no longer be valid to take
// the minimum or maximum of the ratios of the widths and heights of the
// page rect and the composition bounds).
MOZ_ASSERT(mFrameMetrics.IsRootContent());
MOZ_ASSERT(mFrameMetrics.GetZoom().AreScalesSame());
SetState(ANIMATING_ZOOM);
{
ReentrantMonitorAutoEnter lock(mMonitor);
ParentLayerRect compositionBounds = mFrameMetrics.GetCompositionBounds();
CSSRect cssPageRect = mFrameMetrics.GetScrollableRect();
CSSPoint scrollOffset = mFrameMetrics.GetScrollOffset();
CSSToParentLayerScale currentZoom = mFrameMetrics.GetZoom().ToScaleFactor();
CSSToParentLayerScale targetZoom;
// The minimum zoom to prevent over-zoom-out.
// If the zoom factor is lower than this (i.e. we are zoomed more into the page),
// then the CSS content rect, in layers pixels, will be smaller than the
// composition bounds. If this happens, we can't fill the target composited
// area with this frame.
CSSToParentLayerScale localMinZoom(std::max(mZoomConstraints.mMinZoom.scale,
std::max(compositionBounds.width / cssPageRect.width,
compositionBounds.height / cssPageRect.height)));
CSSToParentLayerScale localMaxZoom = mZoomConstraints.mMaxZoom;
if (!aRect.IsEmpty()) {
// Intersect the zoom-to-rect to the CSS rect to make sure it fits.
aRect = aRect.Intersect(cssPageRect);
targetZoom = CSSToParentLayerScale(std::min(compositionBounds.width / aRect.width,
compositionBounds.height / aRect.height));
}
// 1. If the rect is empty, the content-side logic for handling a double-tap
// requested that we zoom out.
// 2. currentZoom is equal to mZoomConstraints.mMaxZoom and user still double-tapping it
// 3. currentZoom is equal to localMinZoom and user still double-tapping it
// Treat these three cases as a request to zoom out as much as possible.
bool zoomOut;
if (aFlags & DISABLE_ZOOM_OUT) {
zoomOut = false;
} else {
zoomOut = aRect.IsEmpty() ||
(currentZoom == localMaxZoom && targetZoom >= localMaxZoom) ||
(currentZoom == localMinZoom && targetZoom <= localMinZoom);
}
if (zoomOut) {
CSSSize compositedSize = mFrameMetrics.CalculateCompositedSizeInCssPixels();
float y = scrollOffset.y;
float newHeight =
cssPageRect.width * (compositedSize.height / compositedSize.width);
float dh = compositedSize.height - newHeight;
aRect = CSSRect(0.0f,
y + dh/2,
cssPageRect.width,
newHeight);
aRect = aRect.Intersect(cssPageRect);
targetZoom = CSSToParentLayerScale(std::min(compositionBounds.width / aRect.width,
compositionBounds.height / aRect.height));
}
targetZoom.scale = clamped(targetZoom.scale, localMinZoom.scale, localMaxZoom.scale);
FrameMetrics endZoomToMetrics = mFrameMetrics;
if (aFlags & PAN_INTO_VIEW_ONLY) {
targetZoom = currentZoom;
} else if(aFlags & ONLY_ZOOM_TO_DEFAULT_SCALE) {
CSSToParentLayerScale zoomAtDefaultScale =
mFrameMetrics.GetDevPixelsPerCSSPixel() * LayoutDeviceToParentLayerScale(1.0);
if (targetZoom.scale > zoomAtDefaultScale.scale) {
// Only change the zoom if we are less than the default zoom
if (currentZoom.scale < zoomAtDefaultScale.scale) {
targetZoom = zoomAtDefaultScale;
} else {
targetZoom = currentZoom;
}
}
}
endZoomToMetrics.SetZoom(CSSToParentLayerScale2D(targetZoom));
// Adjust the zoomToRect to a sensible position to prevent overscrolling.
CSSSize sizeAfterZoom = endZoomToMetrics.CalculateCompositedSizeInCssPixels();
// Vertically center the zoomed element in the screen.
if (!zoomOut && (sizeAfterZoom.height > aRect.height)) {
aRect.y -= (sizeAfterZoom.height - aRect.height) * 0.5f;
if (aRect.y < 0.0f) {
aRect.y = 0.0f;
}
}
// If either of these conditions are met, the page will be
// overscrolled after zoomed
if (aRect.y + sizeAfterZoom.height > cssPageRect.height) {
aRect.y = cssPageRect.height - sizeAfterZoom.height;
aRect.y = aRect.y > 0 ? aRect.y : 0;
}
if (aRect.x + sizeAfterZoom.width > cssPageRect.width) {
aRect.x = cssPageRect.width - sizeAfterZoom.width;
aRect.x = aRect.x > 0 ? aRect.x : 0;
}
endZoomToMetrics.SetScrollOffset(aRect.TopLeft());
StartAnimation(new ZoomAnimation(
mFrameMetrics.GetScrollOffset(),
mFrameMetrics.GetZoom(),
endZoomToMetrics.GetScrollOffset(),
endZoomToMetrics.GetZoom()));
// Schedule a repaint now, so the new displayport will be painted before the
// animation finishes.
ParentLayerPoint velocity(0, 0);
endZoomToMetrics.SetDisplayPortMargins(
CalculatePendingDisplayPort(endZoomToMetrics, velocity));
endZoomToMetrics.SetUseDisplayPortMargins(true);
endZoomToMetrics.SetPaintRequestTime(TimeStamp::Now());
endZoomToMetrics.SetRepaintDrivenByUserAction(true);
RefPtr<GeckoContentController> controller = GetGeckoContentController();
if (!controller) {
return;
}
if (controller->IsRepaintThread()) {
RequestContentRepaint(endZoomToMetrics, velocity);
} else {
// use a local var to resolve the function overload
auto func = static_cast<void (AsyncPanZoomController::*)(const FrameMetrics&, const ParentLayerPoint&)>
(&AsyncPanZoomController::RequestContentRepaint);
controller->DispatchToRepaintThread(
NewRunnableMethod<FrameMetrics, ParentLayerPoint>(
this, func, endZoomToMetrics, velocity));
}
}
}
CancelableBlockState*
AsyncPanZoomController::GetCurrentInputBlock() const
{
return GetInputQueue()->GetCurrentBlock();
}
TouchBlockState*
AsyncPanZoomController::GetCurrentTouchBlock() const
{
return GetInputQueue()->GetCurrentTouchBlock();
}
PanGestureBlockState*
AsyncPanZoomController::GetCurrentPanGestureBlock() const
{
return GetInputQueue()->GetCurrentPanGestureBlock();
}
void
AsyncPanZoomController::ResetTouchInputState()
{
MultiTouchInput cancel(MultiTouchInput::MULTITOUCH_CANCEL, 0, TimeStamp::Now(), 0);
RefPtr<GestureEventListener> listener = GetGestureEventListener();
if (listener) {
listener->HandleInputEvent(cancel);
}
CancelAnimationAndGestureState();
// Clear overscroll along the entire handoff chain, in case an APZC
// later in the chain is overscrolled.
if (TouchBlockState* block = GetCurrentTouchBlock()) {
block->GetOverscrollHandoffChain()->ClearOverscroll();
}
}
void
AsyncPanZoomController::CancelAnimationAndGestureState()
{
mX.CancelGesture();
mY.CancelGesture();
CancelAnimation(CancelAnimationFlags::ScrollSnap);
}
bool
AsyncPanZoomController::HasReadyTouchBlock() const
{
return GetInputQueue()->HasReadyTouchBlock();
}
void AsyncPanZoomController::SetState(PanZoomState aNewState)
{
PanZoomState oldState;
// Intentional scoping for mutex
{
ReentrantMonitorAutoEnter lock(mMonitor);
APZC_LOG("%p changing from state %d to %d\n", this, mState, aNewState);
oldState = mState;
mState = aNewState;
}
DispatchStateChangeNotification(oldState, aNewState);
}
void AsyncPanZoomController::DispatchStateChangeNotification(PanZoomState aOldState,
PanZoomState aNewState)
{
{ // scope the lock
ReentrantMonitorAutoEnter lock(mMonitor);
if (mNotificationBlockers > 0) {
return;
}
}
if (RefPtr<GeckoContentController> controller = GetGeckoContentController()) {
if (!IsTransformingState(aOldState) && IsTransformingState(aNewState)) {
controller->NotifyAPZStateChange(
GetGuid(), APZStateChange::eTransformBegin);
#if defined(XP_WIN) || defined(MOZ_WIDGET_GTK)
// Let the compositor know about scroll state changes so it can manage
// windowed plugins.
if (gfxPrefs::HidePluginsForScroll() && mCompositorController) {
mCompositorController->ScheduleHideAllPluginWindows();
}
#endif
} else if (IsTransformingState(aOldState) && !IsTransformingState(aNewState)) {
controller->NotifyAPZStateChange(
GetGuid(), APZStateChange::eTransformEnd);
#if defined(XP_WIN) || defined(MOZ_WIDGET_GTK)
if (gfxPrefs::HidePluginsForScroll() && mCompositorController) {
mCompositorController->ScheduleShowAllPluginWindows();
}
#endif
}
}
}
bool AsyncPanZoomController::IsTransformingState(PanZoomState aState) {
return !(aState == NOTHING || aState == TOUCHING);
}
bool AsyncPanZoomController::IsInPanningState() const {
return (mState == PANNING || mState == PANNING_LOCKED_X || mState == PANNING_LOCKED_Y);
}
void AsyncPanZoomController::UpdateZoomConstraints(const ZoomConstraints& aConstraints) {
APZC_LOG("%p updating zoom constraints to %d %d %f %f\n", this, aConstraints.mAllowZoom,
aConstraints.mAllowDoubleTapZoom, aConstraints.mMinZoom.scale, aConstraints.mMaxZoom.scale);
if (IsNaN(aConstraints.mMinZoom.scale) || IsNaN(aConstraints.mMaxZoom.scale)) {
NS_WARNING("APZC received zoom constraints with NaN values; dropping...");
return;
}
CSSToParentLayerScale min = mFrameMetrics.GetDevPixelsPerCSSPixel()
* kViewportMinScale / ParentLayerToScreenScale(1);
CSSToParentLayerScale max = mFrameMetrics.GetDevPixelsPerCSSPixel()
* kViewportMaxScale / ParentLayerToScreenScale(1);
// inf float values and other bad cases should be sanitized by the code below.
mZoomConstraints.mAllowZoom = aConstraints.mAllowZoom;
mZoomConstraints.mAllowDoubleTapZoom = aConstraints.mAllowDoubleTapZoom;
mZoomConstraints.mMinZoom = (min > aConstraints.mMinZoom ? min : aConstraints.mMinZoom);
mZoomConstraints.mMaxZoom = (max > aConstraints.mMaxZoom ? aConstraints.mMaxZoom : max);
if (mZoomConstraints.mMaxZoom < mZoomConstraints.mMinZoom) {
mZoomConstraints.mMaxZoom = mZoomConstraints.mMinZoom;
}
}
ZoomConstraints
AsyncPanZoomController::GetZoomConstraints() const
{
return mZoomConstraints;
}
void AsyncPanZoomController::PostDelayedTask(already_AddRefed<Runnable> aTask, int aDelayMs) {
APZThreadUtils::AssertOnControllerThread();
RefPtr<Runnable> task = aTask;
RefPtr<GeckoContentController> controller = GetGeckoContentController();
if (controller) {
controller->PostDelayedTask(task.forget(), aDelayMs);
}
// If there is no controller, that means this APZC has been destroyed, and
// we probably don't need to run the task. It will get destroyed when the
// RefPtr goes out of scope.
}
bool AsyncPanZoomController::Matches(const ScrollableLayerGuid& aGuid)
{
return aGuid == GetGuid();
}
bool AsyncPanZoomController::HasTreeManager(const APZCTreeManager* aTreeManager) const
{
return GetApzcTreeManager() == aTreeManager;
}
void AsyncPanZoomController::GetGuid(ScrollableLayerGuid* aGuidOut) const
{
if (aGuidOut) {
*aGuidOut = GetGuid();
}
}
ScrollableLayerGuid AsyncPanZoomController::GetGuid() const
{
return ScrollableLayerGuid(mLayersId, mFrameMetrics);
}
void AsyncPanZoomController::UpdateSharedCompositorFrameMetrics()
{
mMonitor.AssertCurrentThreadIn();
FrameMetrics* frame = mSharedFrameMetricsBuffer ?
static_cast<FrameMetrics*>(mSharedFrameMetricsBuffer->memory()) : nullptr;
if (frame && mSharedLock && gfxPrefs::ProgressivePaint()) {
mSharedLock->Lock();
*frame = mFrameMetrics;
mSharedLock->Unlock();
}
}
void AsyncPanZoomController::ShareCompositorFrameMetrics()
{
APZThreadUtils::AssertOnCompositorThread();
// Only create the shared memory buffer if it hasn't already been created,
// we are using progressive tile painting, and we have a
// controller to pass the shared memory back to the content process/thread.
if (!mSharedFrameMetricsBuffer && mMetricsSharingController && gfxPrefs::ProgressivePaint()) {
// Create shared memory and initialize it with the current FrameMetrics value
mSharedFrameMetricsBuffer = new ipc::SharedMemoryBasic;
FrameMetrics* frame = nullptr;
mSharedFrameMetricsBuffer->Create(sizeof(FrameMetrics));
mSharedFrameMetricsBuffer->Map(sizeof(FrameMetrics));
frame = static_cast<FrameMetrics*>(mSharedFrameMetricsBuffer->memory());
if (frame) {
{ // scope the monitor, only needed to copy the FrameMetrics.
ReentrantMonitorAutoEnter lock(mMonitor);
*frame = mFrameMetrics;
}
// Get the process id of the content process
base::ProcessId otherPid = mMetricsSharingController->RemotePid();
ipc::SharedMemoryBasic::Handle mem = ipc::SharedMemoryBasic::NULLHandle();
// Get the shared memory handle to share with the content process
mSharedFrameMetricsBuffer->ShareToProcess(otherPid, &mem);
// Get the cross process mutex handle to share with the content process
mSharedLock = new CrossProcessMutex("AsyncPanZoomControlLock");
CrossProcessMutexHandle handle = mSharedLock->ShareToProcess(otherPid);
// Send the shared memory handle and cross process handle to the content
// process by an asynchronous ipc call. Include the APZC unique ID
// so the content process know which APZC sent this shared FrameMetrics.
if (!mMetricsSharingController->StartSharingMetrics(mem, handle, mLayersId, mAPZCId)) {
APZC_LOG("%p failed to share FrameMetrics with content process.", this);
}
}
}
}
Maybe<CSSPoint> AsyncPanZoomController::FindSnapPointNear(
const CSSPoint& aDestination, nsIScrollableFrame::ScrollUnit aUnit) {
mMonitor.AssertCurrentThreadIn();
APZC_LOG("%p scroll snapping near %s\n", this, Stringify(aDestination).c_str());
CSSRect scrollRange = mFrameMetrics.CalculateScrollRange();
if (Maybe<nsPoint> snapPoint = ScrollSnapUtils::GetSnapPointForDestination(
mScrollMetadata.GetSnapInfo(),
aUnit,
CSSSize::ToAppUnits(mFrameMetrics.CalculateCompositedSizeInCssPixels()),
CSSRect::ToAppUnits(scrollRange),
CSSPoint::ToAppUnits(mFrameMetrics.GetScrollOffset()),
CSSPoint::ToAppUnits(aDestination))) {
CSSPoint cssSnapPoint = CSSPoint::FromAppUnits(snapPoint.ref());
// GetSnapPointForDestination() can produce a destination that's outside
// of the scroll frame's scroll range. Clamp it here (this matches the
// behaviour of the main-thread code path, which clamps it in
// nsGfxScrollFrame::ScrollTo()).
return Some(scrollRange.ClampPoint(cssSnapPoint));
}
return Nothing();
}
void AsyncPanZoomController::ScrollSnapNear(const CSSPoint& aDestination) {
if (Maybe<CSSPoint> snapPoint =
FindSnapPointNear(aDestination, nsIScrollableFrame::DEVICE_PIXELS)) {
if (*snapPoint != mFrameMetrics.GetScrollOffset()) {
APZC_LOG("%p smooth scrolling to snap point %s\n", this, Stringify(*snapPoint).c_str());
SmoothScrollTo(*snapPoint);
}
}
}
void AsyncPanZoomController::ScrollSnap() {
ReentrantMonitorAutoEnter lock(mMonitor);
ScrollSnapNear(mFrameMetrics.GetScrollOffset());
}
void AsyncPanZoomController::ScrollSnapToDestination() {
ReentrantMonitorAutoEnter lock(mMonitor);
float friction = gfxPrefs::APZFlingFriction();
ParentLayerPoint velocity(mX.GetVelocity(), mY.GetVelocity());
ParentLayerPoint predictedDelta;
// "-velocity / log(1.0 - friction)" is the integral of the deceleration
// curve modeled for flings in the "Axis" class.
if (velocity.x != 0.0f) {
predictedDelta.x = -velocity.x / log(1.0 - friction);
}
if (velocity.y != 0.0f) {
predictedDelta.y = -velocity.y / log(1.0 - friction);
}
CSSPoint predictedDestination = mFrameMetrics.GetScrollOffset() + predictedDelta / mFrameMetrics.GetZoom();
// If the fling will overscroll, don't scroll snap, because then the user
// user would not see any overscroll animation.
bool flingWillOverscroll = IsOverscrolled() && ((velocity.x * mX.GetOverscroll() >= 0) ||
(velocity.y * mY.GetOverscroll() >= 0));
if (!flingWillOverscroll) {
APZC_LOG("%p fling snapping. friction: %f velocity: %f, %f "
"predictedDelta: %f, %f position: %f, %f "
"predictedDestination: %f, %f\n",
this, friction, velocity.x, velocity.y, (float)predictedDelta.x,
(float)predictedDelta.y, (float)mFrameMetrics.GetScrollOffset().x,
(float)mFrameMetrics.GetScrollOffset().y,
(float)predictedDestination.x, (float)predictedDestination.y);
ScrollSnapNear(predictedDestination);
}
}
bool AsyncPanZoomController::MaybeAdjustDeltaForScrollSnapping(
const ScrollWheelInput& aEvent,
ParentLayerPoint& aDelta,
CSSPoint& aStartPosition)
{
// Don't scroll snap for pixel scrolls. This matches the main thread
// behaviour in EventStateManager::DoScrollText().
if (aEvent.mDeltaType == ScrollWheelInput::SCROLLDELTA_PIXEL) {
return false;
}
ReentrantMonitorAutoEnter lock(mMonitor);
CSSToParentLayerScale2D zoom = mFrameMetrics.GetZoom();
CSSPoint destination = mFrameMetrics.CalculateScrollRange().ClampPoint(
aStartPosition + (aDelta / zoom));
nsIScrollableFrame::ScrollUnit unit =
ScrollWheelInput::ScrollUnitForDeltaType(aEvent.mDeltaType);
if (Maybe<CSSPoint> snapPoint = FindSnapPointNear(destination, unit)) {
aDelta = (*snapPoint - aStartPosition) * zoom;
aStartPosition = *snapPoint;
return true;
}
return false;
}
} // namespace layers
} // namespace mozilla