| // Copyright 2016 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "content/browser/renderer_host/input/mouse_wheel_event_queue.h" |
| |
| #include "base/memory/ptr_util.h" |
| #include "base/metrics/histogram_macros.h" |
| #include "base/trace_event/trace_event.h" |
| #include "content/common/input/input_event_dispatch_type.h" |
| #include "content/public/common/content_features.h" |
| #include "ui/events/base_event_utils.h" |
| #include "ui/events/blink/web_input_event_traits.h" |
| |
| using blink::WebGestureEvent; |
| using blink::WebInputEvent; |
| using blink::WebMouseWheelEvent; |
| using ui::LatencyInfo; |
| |
| namespace content { |
| |
| // This class represents a single queued mouse wheel event. Its main use |
| // is that it is reported via trace events. |
| class QueuedWebMouseWheelEvent : public MouseWheelEventWithLatencyInfo { |
| public: |
| QueuedWebMouseWheelEvent(const MouseWheelEventWithLatencyInfo& original_event) |
| : MouseWheelEventWithLatencyInfo(original_event) { |
| TRACE_EVENT_ASYNC_BEGIN0("input", "MouseWheelEventQueue::QueueEvent", this); |
| } |
| |
| ~QueuedWebMouseWheelEvent() { |
| TRACE_EVENT_ASYNC_END0("input", "MouseWheelEventQueue::QueueEvent", this); |
| } |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(QueuedWebMouseWheelEvent); |
| }; |
| |
| MouseWheelEventQueue::MouseWheelEventQueue(MouseWheelEventQueueClient* client, |
| bool enable_scroll_latching) |
| : client_(client), |
| needs_scroll_begin_when_scroll_latching_disabled_(true), |
| needs_scroll_end_when_scroll_latching_disabled_(false), |
| scroll_in_progress_(false), |
| enable_scroll_latching_(enable_scroll_latching), |
| enable_async_wheel_events_( |
| base::FeatureList::IsEnabled(features::kAsyncWheelEvents) && |
| enable_scroll_latching), |
| send_wheel_events_async_(false), |
| scrolling_device_(blink::kWebGestureDeviceUninitialized) { |
| DCHECK(client); |
| } |
| |
| MouseWheelEventQueue::~MouseWheelEventQueue() { |
| } |
| |
| void MouseWheelEventQueue::QueueEvent( |
| const MouseWheelEventWithLatencyInfo& event) { |
| TRACE_EVENT0("input", "MouseWheelEventQueue::QueueEvent"); |
| |
| if (event_sent_for_gesture_ack_ && !wheel_queue_.empty()) { |
| QueuedWebMouseWheelEvent* last_event = wheel_queue_.back().get(); |
| if (last_event->CanCoalesceWith(event)) { |
| last_event->CoalesceWith(event); |
| TRACE_EVENT_INSTANT2("input", "MouseWheelEventQueue::CoalescedWheelEvent", |
| TRACE_EVENT_SCOPE_THREAD, "total_dx", |
| last_event->event.delta_x, "total_dy", |
| last_event->event.delta_y); |
| return; |
| } |
| } |
| |
| wheel_queue_.push_back(std::make_unique<QueuedWebMouseWheelEvent>(event)); |
| TryForwardNextEventToRenderer(); |
| LOCAL_HISTOGRAM_COUNTS_100("Renderer.WheelQueueSize", wheel_queue_.size()); |
| } |
| |
| void MouseWheelEventQueue::ProcessMouseWheelAck( |
| InputEventAckSource ack_source, |
| InputEventAckState ack_result, |
| const LatencyInfo& latency_info) { |
| TRACE_EVENT0("input", "MouseWheelEventQueue::ProcessMouseWheelAck"); |
| if (!event_sent_for_gesture_ack_) |
| return; |
| |
| event_sent_for_gesture_ack_->latency.AddNewLatencyFrom(latency_info); |
| client_->OnMouseWheelEventAck(*event_sent_for_gesture_ack_, ack_source, |
| ack_result); |
| |
| // If event wasn't consumed then generate a gesture scroll for it. |
| if (ack_result != INPUT_EVENT_ACK_STATE_CONSUMED && |
| ui::WebInputEventTraits::CanCauseScroll( |
| event_sent_for_gesture_ack_->event) && |
| event_sent_for_gesture_ack_->event.resending_plugin_id == -1 && |
| (scrolling_device_ == blink::kWebGestureDeviceUninitialized || |
| scrolling_device_ == blink::kWebGestureDeviceTouchpad)) { |
| WebGestureEvent scroll_update( |
| WebInputEvent::kGestureScrollUpdate, WebInputEvent::kNoModifiers, |
| event_sent_for_gesture_ack_->event.TimeStampSeconds(), |
| blink::kWebGestureDeviceTouchpad); |
| |
| scroll_update.SetPositionInWidget( |
| event_sent_for_gesture_ack_->event.PositionInWidget()); |
| scroll_update.SetPositionInScreen( |
| event_sent_for_gesture_ack_->event.PositionInScreen()); |
| scroll_update.resending_plugin_id = -1; |
| |
| // Swap X & Y if Shift is down and when there is no horizontal movement. |
| if ((event_sent_for_gesture_ack_->event.GetModifiers() & |
| WebInputEvent::kShiftKey) != 0 && |
| event_sent_for_gesture_ack_->event.delta_x == 0) { |
| scroll_update.data.scroll_update.delta_x = |
| event_sent_for_gesture_ack_->event.delta_y; |
| scroll_update.data.scroll_update.delta_y = |
| event_sent_for_gesture_ack_->event.delta_x; |
| } else { |
| scroll_update.data.scroll_update.delta_x = |
| event_sent_for_gesture_ack_->event.delta_x; |
| scroll_update.data.scroll_update.delta_y = |
| event_sent_for_gesture_ack_->event.delta_y; |
| } |
| // Only OSX populates the phase and momentumPhase; so |
| // |inertialPhase| will be UnknownMomentumPhase on all other platforms. |
| if (event_sent_for_gesture_ack_->event.momentum_phase != |
| blink::WebMouseWheelEvent::kPhaseNone) { |
| scroll_update.data.scroll_update.inertial_phase = |
| WebGestureEvent::kMomentumPhase; |
| } else if (event_sent_for_gesture_ack_->event.phase != |
| blink::WebMouseWheelEvent::kPhaseNone) { |
| scroll_update.data.scroll_update.inertial_phase = |
| WebGestureEvent::kNonMomentumPhase; |
| } |
| if (event_sent_for_gesture_ack_->event.scroll_by_page) { |
| scroll_update.data.scroll_update.delta_units = WebGestureEvent::kPage; |
| |
| // Turn page scrolls into a *single* page scroll because |
| // the magnitude the number of ticks is lost when coalescing. |
| if (scroll_update.data.scroll_update.delta_x) |
| scroll_update.data.scroll_update.delta_x = |
| scroll_update.data.scroll_update.delta_x > 0 ? 1 : -1; |
| if (scroll_update.data.scroll_update.delta_y) |
| scroll_update.data.scroll_update.delta_y = |
| scroll_update.data.scroll_update.delta_y > 0 ? 1 : -1; |
| } else { |
| scroll_update.data.scroll_update.delta_units = |
| event_sent_for_gesture_ack_->event.has_precise_scrolling_deltas |
| ? WebGestureEvent::kPrecisePixels |
| : WebGestureEvent::kPixels; |
| |
| if (event_sent_for_gesture_ack_->event.rails_mode == |
| WebInputEvent::kRailsModeVertical) |
| scroll_update.data.scroll_update.delta_x = 0; |
| if (event_sent_for_gesture_ack_->event.rails_mode == |
| WebInputEvent::kRailsModeHorizontal) |
| scroll_update.data.scroll_update.delta_y = 0; |
| } |
| |
| bool current_phase_ended = false; |
| bool scroll_phase_ended = false; |
| bool momentum_phase_ended = false; |
| bool has_phase_info = false; |
| |
| if (event_sent_for_gesture_ack_->event.phase != |
| blink::WebMouseWheelEvent::kPhaseNone || |
| event_sent_for_gesture_ack_->event.momentum_phase != |
| blink::WebMouseWheelEvent::kPhaseNone) { |
| has_phase_info = true; |
| scroll_phase_ended = event_sent_for_gesture_ack_->event.phase == |
| blink::WebMouseWheelEvent::kPhaseEnded || |
| event_sent_for_gesture_ack_->event.phase == |
| blink::WebMouseWheelEvent::kPhaseCancelled; |
| momentum_phase_ended = |
| event_sent_for_gesture_ack_->event.momentum_phase == |
| blink::WebMouseWheelEvent::kPhaseEnded || |
| event_sent_for_gesture_ack_->event.momentum_phase == |
| blink::WebMouseWheelEvent::kPhaseCancelled; |
| current_phase_ended = scroll_phase_ended || momentum_phase_ended; |
| } |
| |
| bool needs_update = scroll_update.data.scroll_update.delta_x != 0 || |
| scroll_update.data.scroll_update.delta_y != 0; |
| |
| // For every GSU event record whether it is latched or not. |
| if (needs_update) |
| RecordLatchingUmaMetric(scroll_in_progress_); |
| |
| if (enable_scroll_latching_) { |
| bool synthetic = event_sent_for_gesture_ack_->event.has_synthetic_phase; |
| if (event_sent_for_gesture_ack_->event.phase == |
| blink::WebMouseWheelEvent::kPhaseBegan) { |
| // Wheel event with phaseBegan must have non-zero deltas. |
| DCHECK(needs_update); |
| send_wheel_events_async_ = true; |
| SendScrollBegin(scroll_update, synthetic); |
| } |
| |
| if (needs_update) { |
| // It is possible that the wheel event with phaseBegan is consumed and |
| // no GSB is sent. |
| if (!scroll_in_progress_) |
| SendScrollBegin(scroll_update, synthetic); |
| ui::LatencyInfo latency = ui::LatencyInfo(ui::SourceEventType::WHEEL); |
| latency.AddLatencyNumber( |
| ui::INPUT_EVENT_LATENCY_GENERATE_SCROLL_UPDATE_FROM_MOUSE_WHEEL, 0, |
| 0); |
| client_->ForwardGestureEventWithLatencyInfo(scroll_update, latency); |
| } |
| |
| if (current_phase_ended && scroll_in_progress_) { |
| // Send GSE when scroll latching is enabled, GSB is sent, and no fling |
| // is going to happen next. |
| SendScrollEnd(scroll_update, synthetic); |
| } |
| } else { // !enable_scroll_latching_ |
| |
| // If there is no update to send and the current phase is ended yet a GSB |
| // needs to be sent, this event sequence doesn't need to be generated |
| // because the events generated will be a GSB (non-synthetic) and GSE |
| // (non-synthetic). This situation arises when OSX generates double |
| // phase end information. |
| bool empty_sequence = |
| !needs_update && needs_scroll_begin_when_scroll_latching_disabled_ && |
| current_phase_ended && |
| !event_sent_for_gesture_ack_->event.has_synthetic_phase; |
| if (needs_update || !empty_sequence) { |
| if (needs_scroll_begin_when_scroll_latching_disabled_) { |
| // If no GSB has been sent, it will be a non-synthetic GSB. |
| SendScrollBegin(scroll_update, false); |
| } else if (has_phase_info) { |
| // If a GSB has been sent, generate a synthetic GSB if we have phase |
| // information. This should be removed once crbug.com/526463 is |
| // fully implemented. |
| SendScrollBegin(scroll_update, true); |
| } |
| |
| if (needs_update) { |
| ui::LatencyInfo latency = ui::LatencyInfo(ui::SourceEventType::WHEEL); |
| latency.AddLatencyNumber( |
| ui::INPUT_EVENT_LATENCY_GENERATE_SCROLL_UPDATE_FROM_MOUSE_WHEEL, |
| 0, 0); |
| client_->ForwardGestureEventWithLatencyInfo(scroll_update, latency); |
| } |
| |
| if (current_phase_ended) { |
| // Non-synthetic GSEs are sent when the current phase is canceled or |
| // ended. |
| SendScrollEnd(scroll_update, false); |
| } else if (has_phase_info) { |
| // Generate a synthetic GSE for every update to force hit testing so |
| // that the non-latching behavior is preserved. Remove once |
| // crbug.com/526463 is fully implemented. |
| SendScrollEnd(scroll_update, true); |
| } else if (!has_phase_info) { |
| SendScrollEnd(scroll_update, false); |
| } |
| } |
| } |
| } |
| |
| event_sent_for_gesture_ack_.reset(); |
| TryForwardNextEventToRenderer(); |
| } |
| |
| void MouseWheelEventQueue::OnGestureScrollEvent( |
| const GestureEventWithLatencyInfo& gesture_event) { |
| if (gesture_event.event.GetType() == |
| blink::WebInputEvent::kGestureScrollBegin) { |
| scrolling_device_ = gesture_event.event.SourceDevice(); |
| } else if (scrolling_device_ == gesture_event.event.SourceDevice() && |
| (gesture_event.event.GetType() == |
| blink::WebInputEvent::kGestureScrollEnd || |
| (gesture_event.event.GetType() == |
| blink::WebInputEvent::kGestureFlingStart && |
| scrolling_device_ != blink::kWebGestureDeviceTouchpad))) { |
| scrolling_device_ = blink::kWebGestureDeviceUninitialized; |
| } |
| } |
| |
| void MouseWheelEventQueue::TryForwardNextEventToRenderer() { |
| TRACE_EVENT0("input", "MouseWheelEventQueue::TryForwardNextEventToRenderer"); |
| |
| if (wheel_queue_.empty() || event_sent_for_gesture_ack_) |
| return; |
| |
| event_sent_for_gesture_ack_ = std::move(wheel_queue_.front()); |
| wheel_queue_.pop_front(); |
| |
| if (enable_async_wheel_events_) { |
| DCHECK(event_sent_for_gesture_ack_->event.phase != |
| blink::WebMouseWheelEvent::kPhaseNone || |
| event_sent_for_gesture_ack_->event.momentum_phase != |
| blink::WebMouseWheelEvent::kPhaseNone); |
| if (event_sent_for_gesture_ack_->event.phase == |
| blink::WebMouseWheelEvent::kPhaseBegan) { |
| send_wheel_events_async_ = false; |
| } else if (send_wheel_events_async_) { |
| event_sent_for_gesture_ack_->event.dispatch_type = |
| WebInputEvent::kEventNonBlocking; |
| } |
| } |
| |
| client_->SendMouseWheelEventImmediately(*event_sent_for_gesture_ack_); |
| } |
| |
| void MouseWheelEventQueue::SendScrollEnd(WebGestureEvent update_event, |
| bool synthetic) { |
| DCHECK(enable_scroll_latching_ || |
| (synthetic && !needs_scroll_end_when_scroll_latching_disabled_) || |
| needs_scroll_end_when_scroll_latching_disabled_); |
| |
| DCHECK(scroll_in_progress_); |
| scroll_in_progress_ = false; |
| |
| WebGestureEvent scroll_end(update_event); |
| scroll_end.SetTimeStampSeconds( |
| ui::EventTimeStampToSeconds(ui::EventTimeForNow())); |
| scroll_end.SetType(WebInputEvent::kGestureScrollEnd); |
| scroll_end.resending_plugin_id = -1; |
| scroll_end.data.scroll_end.synthetic = synthetic; |
| scroll_end.data.scroll_end.inertial_phase = |
| update_event.data.scroll_update.inertial_phase; |
| scroll_end.data.scroll_end.delta_units = |
| update_event.data.scroll_update.delta_units; |
| |
| if (!synthetic) { |
| needs_scroll_begin_when_scroll_latching_disabled_ = true; |
| needs_scroll_end_when_scroll_latching_disabled_ = false; |
| } |
| client_->ForwardGestureEventWithLatencyInfo( |
| scroll_end, ui::LatencyInfo(ui::SourceEventType::WHEEL)); |
| } |
| |
| void MouseWheelEventQueue::SendScrollBegin( |
| const WebGestureEvent& gesture_update, |
| bool synthetic) { |
| DCHECK(enable_scroll_latching_ || |
| (synthetic && !needs_scroll_begin_when_scroll_latching_disabled_) || |
| needs_scroll_begin_when_scroll_latching_disabled_); |
| |
| DCHECK(!scroll_in_progress_); |
| scroll_in_progress_ = true; |
| |
| WebGestureEvent scroll_begin(gesture_update); |
| scroll_begin.SetType(WebInputEvent::kGestureScrollBegin); |
| scroll_begin.data.scroll_begin.synthetic = synthetic; |
| scroll_begin.data.scroll_begin.inertial_phase = |
| gesture_update.data.scroll_update.inertial_phase; |
| scroll_begin.data.scroll_begin.delta_x_hint = |
| gesture_update.data.scroll_update.delta_x; |
| scroll_begin.data.scroll_begin.delta_y_hint = |
| gesture_update.data.scroll_update.delta_y; |
| scroll_begin.data.scroll_begin.target_viewport = false; |
| scroll_begin.data.scroll_begin.delta_hint_units = |
| gesture_update.data.scroll_update.delta_units; |
| |
| needs_scroll_begin_when_scroll_latching_disabled_ = false; |
| needs_scroll_end_when_scroll_latching_disabled_ = true; |
| client_->ForwardGestureEventWithLatencyInfo( |
| scroll_begin, ui::LatencyInfo(ui::SourceEventType::WHEEL)); |
| } |
| |
| void MouseWheelEventQueue::RecordLatchingUmaMetric(bool latched) { |
| UMA_HISTOGRAM_BOOLEAN("WheelScrolling.WasLatched", latched); |
| } |
| |
| } // namespace content |
