1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/layers/apz/src/AsyncPanZoomController.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,984 @@
1.4 +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim: set sw=2 ts=8 et tw=80 : */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#ifndef mozilla_layers_AsyncPanZoomController_h
1.11 +#define mozilla_layers_AsyncPanZoomController_h
1.12 +
1.13 +#include "CrossProcessMutex.h"
1.14 +#include "mozilla/layers/GeckoContentController.h"
1.15 +#include "mozilla/Attributes.h"
1.16 +#include "mozilla/EventForwards.h"
1.17 +#include "mozilla/Monitor.h"
1.18 +#include "mozilla/ReentrantMonitor.h"
1.19 +#include "mozilla/RefPtr.h"
1.20 +#include "mozilla/Atomics.h"
1.21 +#include "InputData.h"
1.22 +#include "Axis.h"
1.23 +#include "TaskThrottler.h"
1.24 +#include "gfx3DMatrix.h"
1.25 +
1.26 +#include "base/message_loop.h"
1.27 +
1.28 +namespace mozilla {
1.29 +
1.30 +namespace ipc {
1.31 +
1.32 +class SharedMemoryBasic;
1.33 +
1.34 +}
1.35 +
1.36 +namespace layers {
1.37 +
1.38 +struct ScrollableLayerGuid;
1.39 +class CompositorParent;
1.40 +class GestureEventListener;
1.41 +class ContainerLayer;
1.42 +class PCompositorParent;
1.43 +class ViewTransform;
1.44 +class APZCTreeManager;
1.45 +class AsyncPanZoomAnimation;
1.46 +class FlingAnimation;
1.47 +
1.48 +/**
1.49 + * Controller for all panning and zooming logic. Any time a user input is
1.50 + * detected and it must be processed in some way to affect what the user sees,
1.51 + * it goes through here. Listens for any input event from InputData and can
1.52 + * optionally handle WidgetGUIEvent-derived touch events, but this must be done
1.53 + * on the main thread. Note that this class completely cross-platform.
1.54 + *
1.55 + * Input events originate on the UI thread of the platform that this runs on,
1.56 + * and are then sent to this class. This class processes the event in some way;
1.57 + * for example, a touch move will usually lead to a panning of content (though
1.58 + * of course there are exceptions, such as if content preventDefaults the event,
1.59 + * or if the target frame is not scrollable). The compositor interacts with this
1.60 + * class by locking it and querying it for the current transform matrix based on
1.61 + * the panning and zooming logic that was invoked on the UI thread.
1.62 + *
1.63 + * Currently, each outer DOM window (i.e. a website in a tab, but not any
1.64 + * subframes) has its own AsyncPanZoomController. In the future, to support
1.65 + * asynchronously scrolled subframes, we want to have one AsyncPanZoomController
1.66 + * per frame.
1.67 + */
1.68 +class AsyncPanZoomController {
1.69 + NS_INLINE_DECL_THREADSAFE_REFCOUNTING(AsyncPanZoomController)
1.70 +
1.71 + typedef mozilla::MonitorAutoLock MonitorAutoLock;
1.72 + typedef uint32_t TouchBehaviorFlags;
1.73 +
1.74 +public:
1.75 + enum GestureBehavior {
1.76 + // The platform code is responsible for forwarding gesture events here. We
1.77 + // will not attempt to generate gesture events from MultiTouchInputs.
1.78 + DEFAULT_GESTURES,
1.79 + // An instance of GestureEventListener is used to detect gestures. This is
1.80 + // handled completely internally within this class.
1.81 + USE_GESTURE_DETECTOR
1.82 + };
1.83 +
1.84 + /**
1.85 + * Constant describing the tolerance in distance we use, multiplied by the
1.86 + * device DPI, before we start panning the screen. This is to prevent us from
1.87 + * accidentally processing taps as touch moves, and from very short/accidental
1.88 + * touches moving the screen.
1.89 + */
1.90 + static float GetTouchStartTolerance();
1.91 +
1.92 + AsyncPanZoomController(uint64_t aLayersId,
1.93 + APZCTreeManager* aTreeManager,
1.94 + GeckoContentController* aController,
1.95 + GestureBehavior aGestures = DEFAULT_GESTURES);
1.96 +
1.97 + // --------------------------------------------------------------------------
1.98 + // These methods must only be called on the gecko thread.
1.99 + //
1.100 +
1.101 + /**
1.102 + * Read the various prefs and do any global initialization for all APZC instances.
1.103 + * This must be run on the gecko thread before any APZC instances are actually
1.104 + * used for anything meaningful.
1.105 + */
1.106 + static void InitializeGlobalState();
1.107 +
1.108 + // --------------------------------------------------------------------------
1.109 + // These methods must only be called on the controller/UI thread.
1.110 + //
1.111 +
1.112 + /**
1.113 + * General handler for incoming input events. Manipulates the frame metrics
1.114 + * based on what type of input it is. For example, a PinchGestureEvent will
1.115 + * cause scaling. This should only be called externally to this class.
1.116 + * HandleInputEvent() should be used internally.
1.117 + */
1.118 + nsEventStatus ReceiveInputEvent(const InputData& aEvent);
1.119 +
1.120 + /**
1.121 + * Kicks an animation to zoom to a rect. This may be either a zoom out or zoom
1.122 + * in. The actual animation is done on the compositor thread after being set
1.123 + * up.
1.124 + */
1.125 + void ZoomToRect(CSSRect aRect);
1.126 +
1.127 + /**
1.128 + * If we have touch listeners, this should always be called when we know
1.129 + * definitively whether or not content has preventDefaulted any touch events
1.130 + * that have come in. If |aPreventDefault| is true, any touch events in the
1.131 + * queue will be discarded.
1.132 + */
1.133 + void ContentReceivedTouch(bool aPreventDefault);
1.134 +
1.135 + /**
1.136 + * Updates any zoom constraints contained in the <meta name="viewport"> tag.
1.137 + */
1.138 + void UpdateZoomConstraints(const ZoomConstraints& aConstraints);
1.139 +
1.140 + /**
1.141 + * Return the zoom constraints last set for this APZC (in the constructor
1.142 + * or in UpdateZoomConstraints()).
1.143 + */
1.144 + ZoomConstraints GetZoomConstraints() const;
1.145 +
1.146 + /**
1.147 + * Schedules a runnable to run on the controller/UI thread at some time
1.148 + * in the future.
1.149 + */
1.150 + void PostDelayedTask(Task* aTask, int aDelayMs);
1.151 +
1.152 + // --------------------------------------------------------------------------
1.153 + // These methods must only be called on the compositor thread.
1.154 + //
1.155 +
1.156 + bool UpdateAnimation(const TimeStamp& aSampleTime);
1.157 +
1.158 + /**
1.159 + * The compositor calls this when it's about to draw pannable/zoomable content
1.160 + * and is setting up transforms for compositing the layer tree. This is not
1.161 + * idempotent. For example, a fling transform can be applied each time this is
1.162 + * called (though not necessarily). |aSampleTime| is the time that this is
1.163 + * sampled at; this is used for interpolating animations. Calling this sets a
1.164 + * new transform in |aNewTransform| which should be multiplied to the transform
1.165 + * in the shadow layer corresponding to this APZC.
1.166 + *
1.167 + * Return value indicates whether or not any currently running animation
1.168 + * should continue. That is, if true, the compositor should schedule another
1.169 + * composite.
1.170 + */
1.171 + bool SampleContentTransformForFrame(const TimeStamp& aSampleTime,
1.172 + ViewTransform* aNewTransform,
1.173 + ScreenPoint& aScrollOffset);
1.174 +
1.175 + /**
1.176 + * A shadow layer update has arrived. |aLayerMetrics| is the new FrameMetrics
1.177 + * for the container layer corresponding to this APZC.
1.178 + * |aIsFirstPaint| is a flag passed from the shadow
1.179 + * layers code indicating that the frame metrics being sent with this call are
1.180 + * the initial metrics and the initial paint of the frame has just happened.
1.181 + */
1.182 + void NotifyLayersUpdated(const FrameMetrics& aLayerMetrics, bool aIsFirstPaint);
1.183 +
1.184 + /**
1.185 + * The platform implementation must set the compositor parent so that we can
1.186 + * request composites.
1.187 + */
1.188 + void SetCompositorParent(CompositorParent* aCompositorParent);
1.189 +
1.190 + /**
1.191 + * The platform implementation must set the cross process compositor if
1.192 + * there is one associated with the layer tree. The cross process compositor
1.193 + * allows the APZC to share its FrameMetrics with the content process.
1.194 + * The shared FrameMetrics is used in progressive paint updates.
1.195 + */
1.196 + void SetCrossProcessCompositorParent(PCompositorParent* aCrossProcessCompositorParent);
1.197 +
1.198 + // --------------------------------------------------------------------------
1.199 + // These methods can be called from any thread.
1.200 + //
1.201 +
1.202 + /**
1.203 + * Shut down the controller/UI thread state and prepare to be
1.204 + * deleted (which may happen from any thread).
1.205 + */
1.206 + void Destroy();
1.207 +
1.208 + /**
1.209 + * Returns true if Destroy() has already been called on this APZC instance.
1.210 + */
1.211 + bool IsDestroyed();
1.212 +
1.213 + /**
1.214 + * Returns the incremental transformation corresponding to the async pan/zoom
1.215 + * in progress. That is, when this transform is multiplied with the layer's
1.216 + * existing transform, it will make the layer appear with the desired pan/zoom
1.217 + * amount.
1.218 + */
1.219 + ViewTransform GetCurrentAsyncTransform();
1.220 +
1.221 + /**
1.222 + * Returns the part of the async transform that will remain once Gecko does a
1.223 + * repaint at the desired metrics. That is, in the steady state:
1.224 + * gfx3DMatrix(GetCurrentAsyncTransform()) === GetNontransientAsyncTransform()
1.225 + */
1.226 + gfx3DMatrix GetNontransientAsyncTransform();
1.227 +
1.228 + /**
1.229 + * Returns the transform to take something from the coordinate space of the
1.230 + * last thing we know gecko painted, to the coordinate space of the last thing
1.231 + * we asked gecko to paint. In cases where that last request has not yet been
1.232 + * processed, this is needed to transform input events properly into a space
1.233 + * gecko will understand.
1.234 + */
1.235 + gfx3DMatrix GetTransformToLastDispatchedPaint();
1.236 +
1.237 + /**
1.238 + * Recalculates the displayport. Ideally, this should paint an area bigger
1.239 + * than the composite-to dimensions so that when you scroll down, you don't
1.240 + * checkerboard immediately. This includes a bunch of logic, including
1.241 + * algorithms to bias painting in the direction of the velocity.
1.242 + */
1.243 + static const LayerMargin CalculatePendingDisplayPort(
1.244 + const FrameMetrics& aFrameMetrics,
1.245 + const ScreenPoint& aVelocity,
1.246 + double aEstimatedPaintDuration);
1.247 +
1.248 + /**
1.249 + * Send an mozbrowserasyncscroll event.
1.250 + * *** The monitor must be held while calling this.
1.251 + */
1.252 + void SendAsyncScrollEvent();
1.253 +
1.254 + /**
1.255 + * Handler for events which should not be intercepted by the touch listener.
1.256 + * Does the work for ReceiveInputEvent().
1.257 + */
1.258 + nsEventStatus HandleInputEvent(const InputData& aEvent);
1.259 +
1.260 + /**
1.261 + * Handler for gesture events.
1.262 + * Currently some gestures are detected in GestureEventListener that calls
1.263 + * APZC back through this handler in order to avoid recursive calls to
1.264 + * APZC::HandleInputEvent() which is supposed to do the work for
1.265 + * ReceiveInputEvent().
1.266 + */
1.267 + nsEventStatus HandleGestureEvent(const InputData& aEvent);
1.268 +
1.269 + /**
1.270 + * Populates the provided object (if non-null) with the scrollable guid of this apzc.
1.271 + */
1.272 + void GetGuid(ScrollableLayerGuid* aGuidOut);
1.273 +
1.274 + /**
1.275 + * Returns the scrollable guid of this apzc.
1.276 + */
1.277 + ScrollableLayerGuid GetGuid();
1.278 +
1.279 + /**
1.280 + * Returns true if this APZC instance is for the layer identified by the guid.
1.281 + */
1.282 + bool Matches(const ScrollableLayerGuid& aGuid);
1.283 +
1.284 + /**
1.285 + * Sync panning and zooming animation using a fixed frame time.
1.286 + * This will ensure that we animate the APZC correctly with other external
1.287 + * animations to the same timestamp.
1.288 + */
1.289 + static void SetFrameTime(const TimeStamp& aMilliseconds);
1.290 +
1.291 + void StartAnimation(AsyncPanZoomAnimation* aAnimation);
1.292 +
1.293 + /**
1.294 + * Cancels any currently running animation. Note that all this does is set the
1.295 + * state of the AsyncPanZoomController back to NOTHING, but it is the
1.296 + * animation's responsibility to check this before advancing.
1.297 + */
1.298 + void CancelAnimation();
1.299 +
1.300 + /**
1.301 + * Take over a fling with the given velocity from another APZC. Used for
1.302 + * during overscroll handoff for a fling.
1.303 + */
1.304 + void TakeOverFling(ScreenPoint aVelocity);
1.305 +
1.306 + /**
1.307 + * Returns allowed touch behavior for the given point on the scrollable layer.
1.308 + * Internally performs a kind of hit testing based on the regions constructed
1.309 + * on the main thread and attached to the current scrollable layer. Each of such regions
1.310 + * contains info about allowed touch behavior. If regions info isn't enough it returns
1.311 + * UNKNOWN value and we should switch to the fallback approach - asking content.
1.312 + * TODO: for now it's only a stub and returns hardcoded magic value. As soon as bug 928833
1.313 + * is done we should integrate its logic here.
1.314 + */
1.315 + TouchBehaviorFlags GetAllowedTouchBehavior(ScreenIntPoint& aPoint);
1.316 +
1.317 + /**
1.318 + * Sets allowed touch behavior for current touch session.
1.319 + * This method is invoked by the APZCTreeManager which in its turn invoked by
1.320 + * the widget after performing touch-action values retrieving.
1.321 + * Must be called after receiving the TOUCH_START even that started the
1.322 + * touch session.
1.323 + */
1.324 + void SetAllowedTouchBehavior(const nsTArray<TouchBehaviorFlags>& aBehaviors);
1.325 +
1.326 + /**
1.327 + * Returns whether this APZC is for an element marked with the 'scrollgrab'
1.328 + * attribute.
1.329 + */
1.330 + bool HasScrollgrab() const { return mFrameMetrics.mHasScrollgrab; }
1.331 +
1.332 + /**
1.333 + * Set an extra offset for testing async scrolling.
1.334 + */
1.335 + void SetTestAsyncScrollOffset(const CSSPoint& aPoint)
1.336 + {
1.337 + mTestAsyncScrollOffset = aPoint;
1.338 + }
1.339 +
1.340 + /**
1.341 + * Returns whether this APZC has room to be panned (in any direction).
1.342 + */
1.343 + bool IsPannable() const;
1.344 +
1.345 +protected:
1.346 + // Protected destructor, to discourage deletion outside of Release():
1.347 + ~AsyncPanZoomController();
1.348 +
1.349 + /**
1.350 + * Helper method for touches beginning. Sets everything up for panning and any
1.351 + * multitouch gestures.
1.352 + */
1.353 + nsEventStatus OnTouchStart(const MultiTouchInput& aEvent);
1.354 +
1.355 + /**
1.356 + * Helper method for touches moving. Does any transforms needed when panning.
1.357 + */
1.358 + nsEventStatus OnTouchMove(const MultiTouchInput& aEvent);
1.359 +
1.360 + /**
1.361 + * Helper method for touches ending. Redraws the screen if necessary and does
1.362 + * any cleanup after a touch has ended.
1.363 + */
1.364 + nsEventStatus OnTouchEnd(const MultiTouchInput& aEvent);
1.365 +
1.366 + /**
1.367 + * Helper method for touches being cancelled. Treated roughly the same as a
1.368 + * touch ending (OnTouchEnd()).
1.369 + */
1.370 + nsEventStatus OnTouchCancel(const MultiTouchInput& aEvent);
1.371 +
1.372 + /**
1.373 + * Helper method for scales beginning. Distinct from the OnTouch* handlers in
1.374 + * that this implies some outside implementation has determined that the user
1.375 + * is pinching.
1.376 + */
1.377 + nsEventStatus OnScaleBegin(const PinchGestureInput& aEvent);
1.378 +
1.379 + /**
1.380 + * Helper method for scaling. As the user moves their fingers when pinching,
1.381 + * this changes the scale of the page.
1.382 + */
1.383 + nsEventStatus OnScale(const PinchGestureInput& aEvent);
1.384 +
1.385 + /**
1.386 + * Helper method for scales ending. Redraws the screen if necessary and does
1.387 + * any cleanup after a scale has ended.
1.388 + */
1.389 + nsEventStatus OnScaleEnd(const PinchGestureInput& aEvent);
1.390 +
1.391 + /**
1.392 + * Helper methods for long press gestures.
1.393 + */
1.394 + nsEventStatus OnLongPress(const TapGestureInput& aEvent);
1.395 + nsEventStatus OnLongPressUp(const TapGestureInput& aEvent);
1.396 +
1.397 + /**
1.398 + * Helper method for single tap gestures.
1.399 + */
1.400 + nsEventStatus OnSingleTapUp(const TapGestureInput& aEvent);
1.401 +
1.402 + /**
1.403 + * Helper method for a single tap confirmed.
1.404 + */
1.405 + nsEventStatus OnSingleTapConfirmed(const TapGestureInput& aEvent);
1.406 +
1.407 + /**
1.408 + * Helper method for double taps.
1.409 + */
1.410 + nsEventStatus OnDoubleTap(const TapGestureInput& aEvent);
1.411 +
1.412 + /**
1.413 + * Helper method to cancel any gesture currently going to Gecko. Used
1.414 + * primarily when a user taps the screen over some clickable content but then
1.415 + * pans down instead of letting go (i.e. to cancel a previous touch so that a
1.416 + * new one can properly take effect.
1.417 + */
1.418 + nsEventStatus OnCancelTap(const TapGestureInput& aEvent);
1.419 +
1.420 + /**
1.421 + * Scrolls the viewport by an X,Y offset.
1.422 + */
1.423 + void ScrollBy(const CSSPoint& aOffset);
1.424 +
1.425 + /**
1.426 + * Scales the viewport by an amount (note that it multiplies this scale in to
1.427 + * the current scale, it doesn't set it to |aScale|). Also considers a focus
1.428 + * point so that the page zooms inward/outward from that point.
1.429 + */
1.430 + void ScaleWithFocus(float aScale,
1.431 + const CSSPoint& aFocus);
1.432 +
1.433 + /**
1.434 + * Schedules a composite on the compositor thread. Wrapper for
1.435 + * CompositorParent::ScheduleRenderOnCompositorThread().
1.436 + */
1.437 + void ScheduleComposite();
1.438 +
1.439 + /**
1.440 + * Gets the displacement of the current touch since it began. That is, it is
1.441 + * the distance between the current position and the initial position of the
1.442 + * current touch (this only makes sense if a touch is currently happening and
1.443 + * OnTouchMove() is being invoked).
1.444 + */
1.445 + float PanDistance();
1.446 +
1.447 + /**
1.448 + * Gets a vector of the velocities of each axis.
1.449 + */
1.450 + const ScreenPoint GetVelocityVector();
1.451 +
1.452 + /**
1.453 + * Gets a reference to the first touch point from a MultiTouchInput. This
1.454 + * gets only the first one and assumes the rest are either missing or not
1.455 + * relevant.
1.456 + */
1.457 + ScreenIntPoint& GetFirstTouchScreenPoint(const MultiTouchInput& aEvent);
1.458 +
1.459 + /**
1.460 + * Sets the panning state basing on the pan direction angle and current touch-action value.
1.461 + */
1.462 + void HandlePanningWithTouchAction(double angle, TouchBehaviorFlags value);
1.463 +
1.464 + /**
1.465 + * Sets the panning state ignoring the touch action value.
1.466 + */
1.467 + void HandlePanning(double angle);
1.468 +
1.469 + /**
1.470 + * Sets up anything needed for panning. This takes us out of the "TOUCHING"
1.471 + * state and starts actually panning us.
1.472 + */
1.473 + nsEventStatus StartPanning(const MultiTouchInput& aStartPoint);
1.474 +
1.475 + /**
1.476 + * Wrapper for Axis::UpdateWithTouchAtDevicePoint(). Calls this function for
1.477 + * both axes and factors in the time delta from the last update.
1.478 + */
1.479 + void UpdateWithTouchAtDevicePoint(const MultiTouchInput& aEvent);
1.480 +
1.481 + /**
1.482 + * Does any panning required due to a new touch event.
1.483 + */
1.484 + void TrackTouch(const MultiTouchInput& aEvent);
1.485 +
1.486 + /**
1.487 + * Utility function to send updated FrameMetrics to Gecko so that it can paint
1.488 + * the displayport area. Calls into GeckoContentController to do the actual
1.489 + * work. Note that only one paint request can be active at a time. If a paint
1.490 + * request is made while a paint is currently happening, it gets queued up. If
1.491 + * a new paint request arrives before a paint is completed, the old request
1.492 + * gets discarded.
1.493 + */
1.494 + void RequestContentRepaint();
1.495 +
1.496 + /**
1.497 + * Tell the paint throttler to request a content repaint with the given
1.498 + * metrics. (Helper function used by RequestContentRepaint.)
1.499 + */
1.500 + void RequestContentRepaint(FrameMetrics& aFrameMetrics);
1.501 +
1.502 + /**
1.503 + * Actually send the next pending paint request to gecko.
1.504 + */
1.505 + void DispatchRepaintRequest(const FrameMetrics& aFrameMetrics);
1.506 +
1.507 + /**
1.508 + * Advances a fling by an interpolated amount based on the passed in |aDelta|.
1.509 + * This should be called whenever sampling the content transform for this
1.510 + * frame. Returns true if the fling animation should be advanced by one frame,
1.511 + * or false if there is no fling or the fling has ended.
1.512 + */
1.513 + bool DoFling(const TimeDuration& aDelta);
1.514 +
1.515 + /**
1.516 + * Gets the current frame metrics. This is *not* the Gecko copy stored in the
1.517 + * layers code.
1.518 + */
1.519 + const FrameMetrics& GetFrameMetrics();
1.520 +
1.521 + /**
1.522 + * Sets the timer for content response to a series of touch events, if it
1.523 + * hasn't been already. This is to prevent us from batching up touch events
1.524 + * indefinitely in the case that content doesn't respond with whether or not
1.525 + * it wants to preventDefault. When the timer is fired, the touch event queue
1.526 + * will be flushed.
1.527 + */
1.528 + void SetContentResponseTimer();
1.529 +
1.530 + /**
1.531 + * Timeout function for content response. This should be called on a timer
1.532 + * after we get our first touch event in a batch, under the condition that we
1.533 + * waiting for response from content. If a notification comes indicating whether or not
1.534 + * content preventDefaulted a series of touch events and touch behavior values are
1.535 + * set before the timeout, the timeout should be cancelled.
1.536 + */
1.537 + void TimeoutContentResponse();
1.538 +
1.539 + /**
1.540 + * Timeout function for mozbrowserasyncscroll event. Because we throttle
1.541 + * mozbrowserasyncscroll events in some conditions, this function ensures
1.542 + * that the last mozbrowserasyncscroll event will be fired after a period of
1.543 + * time.
1.544 + */
1.545 + void FireAsyncScrollOnTimeout();
1.546 +
1.547 +private:
1.548 + enum PanZoomState {
1.549 + NOTHING, /* no touch-start events received */
1.550 + FLING, /* all touches removed, but we're still scrolling page */
1.551 + TOUCHING, /* one touch-start event received */
1.552 +
1.553 + PANNING, /* panning the frame */
1.554 + PANNING_LOCKED_X, /* touch-start followed by move (i.e. panning with axis lock) X axis */
1.555 + PANNING_LOCKED_Y, /* as above for Y axis */
1.556 +
1.557 + CROSS_SLIDING_X, /* Panning disabled while user does a horizontal gesture
1.558 + on a vertically-scrollable view. This used for the
1.559 + Windows Metro "cross-slide" gesture. */
1.560 + CROSS_SLIDING_Y, /* as above for Y axis */
1.561 +
1.562 + PINCHING, /* nth touch-start, where n > 1. this mode allows pan and zoom */
1.563 + ANIMATING_ZOOM, /* animated zoom to a new rect */
1.564 + WAITING_CONTENT_RESPONSE, /* a state halfway between NOTHING and TOUCHING - the user has
1.565 + put a finger down, but we don't yet know if a touch listener has
1.566 + prevented the default actions yet and the allowed touch behavior
1.567 + was not set yet. we still need to abort animations. */
1.568 + };
1.569 +
1.570 + // State related to a single touch block. Does not persist across touch blocks.
1.571 + struct TouchBlockState {
1.572 +
1.573 + TouchBlockState()
1.574 + : mAllowedTouchBehaviorSet(false),
1.575 + mPreventDefault(false),
1.576 + mPreventDefaultSet(false),
1.577 + mSingleTapOccurred(false)
1.578 + {}
1.579 +
1.580 + // Values of allowed touch behavior for touch points of this touch block.
1.581 + // Since there are maybe a few current active touch points per time (multitouch case)
1.582 + // and each touch point should have its own value of allowed touch behavior- we're
1.583 + // keeping an array of allowed touch behavior values, not the single value.
1.584 + nsTArray<TouchBehaviorFlags> mAllowedTouchBehaviors;
1.585 +
1.586 + // Specifies whether mAllowedTouchBehaviors is set for this touch events block.
1.587 + bool mAllowedTouchBehaviorSet;
1.588 +
1.589 + // Flag used to specify that content prevented the default behavior of this
1.590 + // touch events block.
1.591 + bool mPreventDefault;
1.592 +
1.593 + // Specifies whether mPreventDefault property is set for this touch events block.
1.594 + bool mPreventDefaultSet;
1.595 +
1.596 + // Specifies whether a single tap event was generated during this touch block.
1.597 + bool mSingleTapOccurred;
1.598 + };
1.599 +
1.600 + /*
1.601 + * Returns whether current touch behavior values allow pinch-zooming.
1.602 + */
1.603 + bool TouchActionAllowPinchZoom();
1.604 +
1.605 + /*
1.606 + * Returns whether current touch behavior values allow double-tap-zooming.
1.607 + */
1.608 + bool TouchActionAllowDoubleTapZoom();
1.609 +
1.610 + /*
1.611 + * Returns allowed touch behavior from the mAllowedTouchBehavior array.
1.612 + * In case apzc didn't receive touch behavior values within the timeout
1.613 + * it returns default value.
1.614 + */
1.615 + TouchBehaviorFlags GetTouchBehavior(uint32_t touchIndex);
1.616 +
1.617 + /**
1.618 + * To move from the WAITING_CONTENT_RESPONSE state to TOUCHING one we need two
1.619 + * conditions set: get content listeners response (whether they called preventDefault)
1.620 + * and get allowed touch behaviors.
1.621 + * This method checks both conditions and changes (or not changes) state
1.622 + * appropriately.
1.623 + */
1.624 + void CheckContentResponse();
1.625 +
1.626 + /**
1.627 + * Helper to set the current state. Holds the monitor before actually setting
1.628 + * it and fires content controller events based on state changes. Always set
1.629 + * the state using this call, do not set it directly.
1.630 + */
1.631 + void SetState(PanZoomState aState);
1.632 +
1.633 + /**
1.634 + * Convert ScreenPoint relative to this APZC to CSSPoint relative
1.635 + * to the parent document. This excludes the transient compositor transform.
1.636 + * NOTE: This must be converted to CSSPoint relative to the child
1.637 + * document before sending over IPC.
1.638 + */
1.639 + bool ConvertToGecko(const ScreenPoint& aPoint, CSSPoint* aOut);
1.640 +
1.641 + /**
1.642 + * Internal helpers for checking general state of this apzc.
1.643 + */
1.644 + bool IsTransformingState(PanZoomState aState);
1.645 + bool IsPanningState(PanZoomState mState);
1.646 +
1.647 + enum AxisLockMode {
1.648 + FREE, /* No locking at all */
1.649 + STANDARD, /* Default axis locking mode that remains locked until pan ends*/
1.650 + STICKY, /* Allow lock to be broken, with hysteresis */
1.651 + };
1.652 +
1.653 + static AxisLockMode GetAxisLockMode();
1.654 +
1.655 + // Convert a point from local screen coordinates to parent layer coordinates.
1.656 + // This is a common operation as inputs from the tree manager are in screen
1.657 + // coordinates but the composition bounds is in parent layer coordinates.
1.658 + ParentLayerPoint ToParentLayerCoords(const ScreenPoint& aPoint);
1.659 +
1.660 + // Update mFrameMetrics.mTransformScale. This should be called whenever
1.661 + // our CSS transform or the non-transient part of our async transform
1.662 + // changes, as it corresponds to the scale portion of those transforms.
1.663 + void UpdateTransformScale();
1.664 +
1.665 + // Helper function for OnSingleTapUp() and OnSingleTapConfirmed().
1.666 + nsEventStatus GenerateSingleTap(const ScreenIntPoint& aPoint, mozilla::Modifiers aModifiers);
1.667 +
1.668 + // Common processing at the end of a touch block.
1.669 + void OnTouchEndOrCancel();
1.670 +
1.671 + uint64_t mLayersId;
1.672 + nsRefPtr<CompositorParent> mCompositorParent;
1.673 + PCompositorParent* mCrossProcessCompositorParent;
1.674 + TaskThrottler mPaintThrottler;
1.675 +
1.676 + /* Access to the following two fields is protected by the mRefPtrMonitor,
1.677 + since they are accessed on the UI thread but can be cleared on the
1.678 + compositor thread. */
1.679 + nsRefPtr<GeckoContentController> mGeckoContentController;
1.680 + nsRefPtr<GestureEventListener> mGestureEventListener;
1.681 + Monitor mRefPtrMonitor;
1.682 +
1.683 + /* Utility functions that return a addrefed pointer to the corresponding fields. */
1.684 + already_AddRefed<GeckoContentController> GetGeckoContentController();
1.685 + already_AddRefed<GestureEventListener> GetGestureEventListener();
1.686 +
1.687 +protected:
1.688 + // Both |mFrameMetrics| and |mLastContentPaintMetrics| are protected by the
1.689 + // monitor. Do not read from or modify either of them without locking.
1.690 + FrameMetrics mFrameMetrics;
1.691 +
1.692 + // Protects |mFrameMetrics|, |mLastContentPaintMetrics|, and |mState|.
1.693 + // Before manipulating |mFrameMetrics| or |mLastContentPaintMetrics|, the
1.694 + // monitor should be held. When setting |mState|, either the SetState()
1.695 + // function can be used, or the monitor can be held and then |mState| updated.
1.696 + // IMPORTANT: See the note about lock ordering at the top of APZCTreeManager.h.
1.697 + // This is mutable to allow entering it from 'const' methods; doing otherwise
1.698 + // would significantly limit what methods could be 'const'.
1.699 + mutable ReentrantMonitor mMonitor;
1.700 +
1.701 + // Specifies whether we should use touch-action css property. Initialized from
1.702 + // the preferences. This property (in comparison with the global one) simplifies
1.703 + // testing apzc with (and without) touch-action property enabled concurrently
1.704 + // (e.g. with the gtest framework).
1.705 + bool mTouchActionPropertyEnabled;
1.706 +
1.707 +private:
1.708 + // Metrics of the container layer corresponding to this APZC. This is
1.709 + // stored here so that it is accessible from the UI/controller thread.
1.710 + // These are the metrics at last content paint, the most recent
1.711 + // values we were notified of in NotifyLayersUpdate(). Since it represents
1.712 + // the Gecko state, it should be used as a basis for untransformation when
1.713 + // sending messages back to Gecko.
1.714 + FrameMetrics mLastContentPaintMetrics;
1.715 + // The last metrics that we requested a paint for. These are used to make sure
1.716 + // that we're not requesting a paint of the same thing that's already drawn.
1.717 + // If we don't do this check, we don't get a ShadowLayersUpdated back.
1.718 + FrameMetrics mLastPaintRequestMetrics;
1.719 + // The last metrics that we actually sent to Gecko. This allows us to transform
1.720 + // inputs into a coordinate space that Gecko knows about. This assumes the pipe
1.721 + // through which input events and repaint requests are sent to Gecko operates
1.722 + // in a FIFO manner.
1.723 + FrameMetrics mLastDispatchedPaintMetrics;
1.724 +
1.725 + nsTArray<MultiTouchInput> mTouchQueue;
1.726 +
1.727 + CancelableTask* mContentResponseTimeoutTask;
1.728 +
1.729 + AxisX mX;
1.730 + AxisY mY;
1.731 +
1.732 + // This flag is set to true when we are in a axis-locked pan as a result of
1.733 + // the touch-action CSS property.
1.734 + bool mPanDirRestricted;
1.735 +
1.736 + // Most up-to-date constraints on zooming. These should always be reasonable
1.737 + // values; for example, allowing a min zoom of 0.0 can cause very bad things
1.738 + // to happen.
1.739 + ZoomConstraints mZoomConstraints;
1.740 +
1.741 + // The last time the compositor has sampled the content transform for this
1.742 + // frame.
1.743 + TimeStamp mLastSampleTime;
1.744 + // The last time a touch event came through on the UI thread.
1.745 + uint32_t mLastEventTime;
1.746 +
1.747 + // Stores the previous focus point if there is a pinch gesture happening. Used
1.748 + // to allow panning by moving multiple fingers (thus moving the focus point).
1.749 + ParentLayerPoint mLastZoomFocus;
1.750 +
1.751 + // Stores the state of panning and zooming this frame. This is protected by
1.752 + // |mMonitor|; that is, it should be held whenever this is updated.
1.753 + PanZoomState mState;
1.754 +
1.755 + // The last time and offset we fire the mozbrowserasyncscroll event when
1.756 + // compositor has sampled the content transform for this frame.
1.757 + TimeStamp mLastAsyncScrollTime;
1.758 + CSSPoint mLastAsyncScrollOffset;
1.759 +
1.760 + // The current offset drawn on the screen, it may not be sent since we have
1.761 + // throttling policy for mozbrowserasyncscroll event.
1.762 + CSSPoint mCurrentAsyncScrollOffset;
1.763 +
1.764 + // The delay task triggered by the throttling mozbrowserasyncscroll event
1.765 + // ensures the last mozbrowserasyncscroll event is always been fired.
1.766 + CancelableTask* mAsyncScrollTimeoutTask;
1.767 +
1.768 + // Flag used to determine whether or not we should try to enter the
1.769 + // WAITING_LISTENERS state. This is used in the case that we are processing a
1.770 + // queued up event block. If set, this means that we are handling this queue
1.771 + // and we don't want to queue the events back up again.
1.772 + bool mHandlingTouchQueue;
1.773 +
1.774 + // Stores information about the current touch block.
1.775 + TouchBlockState mTouchBlockState;
1.776 +
1.777 + // Extra offset to add in SampleContentTransformForFrame for testing
1.778 + CSSPoint mTestAsyncScrollOffset;
1.779 +
1.780 + RefPtr<AsyncPanZoomAnimation> mAnimation;
1.781 +
1.782 + friend class Axis;
1.783 + friend class FlingAnimation;
1.784 +
1.785 +
1.786 + /* ===================================================================
1.787 + * The functions and members in this section are used to build a tree
1.788 + * structure out of APZC instances. This tree can only be walked or
1.789 + * manipulated while holding the lock in the associated APZCTreeManager
1.790 + * instance.
1.791 + */
1.792 +public:
1.793 + void SetLastChild(AsyncPanZoomController* child) {
1.794 + mLastChild = child;
1.795 + if (child) {
1.796 + child->mParent = this;
1.797 + }
1.798 + }
1.799 +
1.800 + void SetPrevSibling(AsyncPanZoomController* sibling) {
1.801 + mPrevSibling = sibling;
1.802 + if (sibling) {
1.803 + sibling->mParent = mParent;
1.804 + }
1.805 + }
1.806 +
1.807 + AsyncPanZoomController* GetLastChild() const { return mLastChild; }
1.808 + AsyncPanZoomController* GetPrevSibling() const { return mPrevSibling; }
1.809 + AsyncPanZoomController* GetParent() const { return mParent; }
1.810 +
1.811 + /* Returns true if there is no APZC higher in the tree with the same
1.812 + * layers id.
1.813 + */
1.814 + bool IsRootForLayersId() const {
1.815 + return !mParent || (mParent->mLayersId != mLayersId);
1.816 + }
1.817 +
1.818 + bool IsRootForLayersId(const uint64_t& aLayersId) const {
1.819 + return (mLayersId == aLayersId) && IsRootForLayersId();
1.820 + }
1.821 +
1.822 +private:
1.823 + // This is a raw pointer to avoid introducing a reference cycle between
1.824 + // AsyncPanZoomController and APZCTreeManager. Since these objects don't
1.825 + // live on the main thread, we can't use the cycle collector with them.
1.826 + // The APZCTreeManager owns the lifetime of the APZCs, so nulling this
1.827 + // pointer out in Destroy() will prevent accessing deleted memory.
1.828 + Atomic<APZCTreeManager*> mTreeManager;
1.829 +
1.830 + nsRefPtr<AsyncPanZoomController> mLastChild;
1.831 + nsRefPtr<AsyncPanZoomController> mPrevSibling;
1.832 + nsRefPtr<AsyncPanZoomController> mParent;
1.833 +
1.834 +
1.835 + /* ===================================================================
1.836 + * The functions and members in this section are used in building the
1.837 + * scroll handoff chain, so that we can have seamless scrolling continue
1.838 + * across APZC instances.
1.839 + */
1.840 +public:
1.841 + void SetScrollHandoffParentId(FrameMetrics::ViewID aScrollParentId) {
1.842 + mScrollParentId = aScrollParentId;
1.843 + }
1.844 +
1.845 + FrameMetrics::ViewID GetScrollHandoffParentId() const {
1.846 + return mScrollParentId;
1.847 + }
1.848 +
1.849 + /**
1.850 + * Attempt to scroll in response to a touch-move from |aStartPoint| to
1.851 + * |aEndPoint|, which are in our (transformed) screen coordinates.
1.852 + * Due to overscroll handling, there may not actually have been a touch-move
1.853 + * at these points, but this function will scroll as if there had been.
1.854 + * If this attempt causes overscroll (i.e. the layer cannot be scrolled
1.855 + * by the entire amount requested), the overscroll is passed back to the
1.856 + * tree manager via APZCTreeManager::DispatchScroll().
1.857 + * |aOverscrollHandoffChainIndex| is used by the tree manager to keep track
1.858 + * of which APZC to hand off the overscroll to; this function increments it
1.859 + * and passes it on to APZCTreeManager::DispatchScroll() in the event of
1.860 + * overscroll.
1.861 + */
1.862 + void AttemptScroll(const ScreenPoint& aStartPoint, const ScreenPoint& aEndPoint,
1.863 + uint32_t aOverscrollHandoffChainIndex = 0);
1.864 +
1.865 + void FlushRepaintForOverscrollHandoff();
1.866 +
1.867 +private:
1.868 + FrameMetrics::ViewID mScrollParentId;
1.869 +
1.870 + /**
1.871 + * A helper function for calling APZCTreeManager::DispatchScroll().
1.872 + * Guards against the case where the APZC is being concurrently destroyed
1.873 + * (and thus mTreeManager is being nulled out).
1.874 + */
1.875 + void CallDispatchScroll(const ScreenPoint& aStartPoint, const ScreenPoint& aEndPoint,
1.876 + uint32_t aOverscrollHandoffChainIndex);
1.877 +
1.878 +
1.879 + /* ===================================================================
1.880 + * The functions and members in this section are used to maintain the
1.881 + * area that this APZC instance is responsible for. This is used when
1.882 + * hit-testing to see which APZC instance should handle touch events.
1.883 + */
1.884 +public:
1.885 + void SetLayerHitTestData(const ParentLayerRect& aRect, const gfx3DMatrix& aTransformToLayer,
1.886 + const gfx3DMatrix& aTransformForLayer) {
1.887 + mVisibleRect = aRect;
1.888 + mAncestorTransform = aTransformToLayer;
1.889 + mCSSTransform = aTransformForLayer;
1.890 + UpdateTransformScale();
1.891 + }
1.892 +
1.893 + gfx3DMatrix GetAncestorTransform() const {
1.894 + return mAncestorTransform;
1.895 + }
1.896 +
1.897 + gfx3DMatrix GetCSSTransform() const {
1.898 + return mCSSTransform;
1.899 + }
1.900 +
1.901 + bool VisibleRegionContains(const ParentLayerPoint& aPoint) const {
1.902 + return mVisibleRect.Contains(aPoint);
1.903 + }
1.904 +
1.905 +private:
1.906 + /* This is the visible region of the layer that this APZC corresponds to, in
1.907 + * that layer's screen pixels (the same coordinate system in which this APZC
1.908 + * receives events in ReceiveInputEvent()). */
1.909 + ParentLayerRect mVisibleRect;
1.910 + /* This is the cumulative CSS transform for all the layers between the parent
1.911 + * APZC and this one (not inclusive) */
1.912 + gfx3DMatrix mAncestorTransform;
1.913 + /* This is the CSS transform for this APZC's layer. */
1.914 + gfx3DMatrix mCSSTransform;
1.915 +
1.916 +
1.917 + /* ===================================================================
1.918 + * The functions and members in this section are used for sharing the
1.919 + * FrameMetrics across processes for the progressive tiling code.
1.920 + */
1.921 +private:
1.922 + /* Unique id assigned to each APZC. Used with ViewID to uniquely identify
1.923 + * shared FrameMeterics used in progressive tile painting. */
1.924 + const uint32_t mAPZCId;
1.925 +
1.926 + ipc::SharedMemoryBasic* mSharedFrameMetricsBuffer;
1.927 + CrossProcessMutex* mSharedLock;
1.928 + /**
1.929 + * Called when ever mFrameMetrics is updated so that if it is being
1.930 + * shared with the content process the shared FrameMetrics may be updated.
1.931 + */
1.932 + void UpdateSharedCompositorFrameMetrics();
1.933 + /**
1.934 + * Create a shared memory buffer for containing the FrameMetrics and
1.935 + * a CrossProcessMutex that may be shared with the content process
1.936 + * for use in progressive tiled update calculations.
1.937 + */
1.938 + void ShareCompositorFrameMetrics();
1.939 +};
1.940 +
1.941 +class AsyncPanZoomAnimation {
1.942 + NS_INLINE_DECL_THREADSAFE_REFCOUNTING(AsyncPanZoomAnimation)
1.943 +
1.944 +public:
1.945 + AsyncPanZoomAnimation(const TimeDuration& aRepaintInterval =
1.946 + TimeDuration::Forever())
1.947 + : mRepaintInterval(aRepaintInterval)
1.948 + { }
1.949 +
1.950 + virtual bool Sample(FrameMetrics& aFrameMetrics,
1.951 + const TimeDuration& aDelta) = 0;
1.952 +
1.953 + /**
1.954 + * Get the deferred tasks in |mDeferredTasks|. See |mDeferredTasks|
1.955 + * for more information.
1.956 + * Clears |mDeferredTasks|.
1.957 + */
1.958 + Vector<Task*> TakeDeferredTasks() {
1.959 + Vector<Task*> result;
1.960 + mDeferredTasks.swap(result);
1.961 + return result;
1.962 + }
1.963 +
1.964 + /**
1.965 + * Specifies how frequently (at most) we want to do repaints during the
1.966 + * animation sequence. TimeDuration::Forever() will cause it to only repaint
1.967 + * at the end of the animation.
1.968 + */
1.969 + TimeDuration mRepaintInterval;
1.970 +
1.971 +protected:
1.972 + // Protected destructor, to discourage deletion outside of Release():
1.973 + virtual ~AsyncPanZoomAnimation()
1.974 + { }
1.975 +
1.976 + /**
1.977 + * Tasks scheduled for execution after the APZC's mMonitor is released.
1.978 + * Derived classes can add tasks here in Sample(), and the APZC can call
1.979 + * ExecuteDeferredTasks() to execute them.
1.980 + */
1.981 + Vector<Task*> mDeferredTasks;
1.982 +};
1.983 +
1.984 +}
1.985 +}
1.986 +
1.987 +#endif // mozilla_layers_PanZoomController_h
