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content / common / input / synthetic_smooth_move_gesture.cc [blame]
// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/common/input/synthetic_smooth_move_gesture.h"
#include <stdint.h>
#include "base/check_op.h"
#include "base/notreached.h"
#include "base/time/time.h"
#include "third_party/blink/public/common/input/synthetic_web_input_event_builders.h"
#include "ui/gfx/geometry/point_f.h"
namespace content {
namespace {
gfx::Vector2dF ProjectScalarOntoVector(float scalar,
const gfx::Vector2dF& vector) {
return gfx::ScaleVector2d(vector, scalar / vector.Length());
}
// returns the animation progress along an arctan curve to provide simple
// ease-in ease-out behavior.
float GetCurvedRatio(const base::TimeTicks& current,
const base::TimeTicks& start,
const base::TimeTicks& end,
int speed_in_pixels_s) {
// Increasing this would make the start and the end of the curv smoother.
// Hence the higher value for the higher speed.
const float kArctanRange = sqrt(static_cast<double>(speed_in_pixels_s)) / 100;
const float kMaxArctan = std::atan(kArctanRange / 2);
const float kMinArctan = std::atan(-kArctanRange / 2);
float linear_ratio = (current - start) / (end - start);
return (std::atan(kArctanRange * linear_ratio - kArctanRange / 2) -
kMinArctan) /
(kMaxArctan - kMinArctan);
}
} // namespace
SyntheticSmoothMoveGestureParams::SyntheticSmoothMoveGestureParams() = default;
SyntheticSmoothMoveGestureParams::SyntheticSmoothMoveGestureParams(
const SyntheticSmoothMoveGestureParams& other) = default;
SyntheticSmoothMoveGestureParams::~SyntheticSmoothMoveGestureParams() = default;
SyntheticGestureParams::GestureType
SyntheticSmoothMoveGestureParams::GetGestureType() const {
return SMOOTH_MOVE_GESTURE;
}
SyntheticSmoothMoveGesture::SyntheticSmoothMoveGesture(
const SyntheticSmoothMoveGestureParams& gesture_params)
: SyntheticGestureBase(gesture_params),
current_move_segment_start_position_(params().start_point) {
CHECK_EQ(SyntheticGestureParams::SMOOTH_MOVE_GESTURE,
gesture_params.GetGestureType());
}
SyntheticSmoothMoveGesture::~SyntheticSmoothMoveGesture() {}
SyntheticGesture::Result SyntheticSmoothMoveGesture::ForwardInputEvents(
const base::TimeTicks& timestamp,
SyntheticGestureTarget* target) {
CHECK(dispatching_controller_);
// Keep this on the stack so we can check if the forwarded event caused the
// deletion of the controller (which owns `this`).
base::WeakPtr<SyntheticGestureController> weak_controller =
dispatching_controller_;
if (state_ == SETUP) {
state_ = STARTED;
current_move_segment_ = -1;
current_move_segment_stop_time_ = timestamp;
}
switch (params().input_type) {
case SyntheticSmoothMoveGestureParams::TOUCH_INPUT:
if (!synthetic_pointer_driver_)
synthetic_pointer_driver_ = SyntheticPointerDriver::Create(
content::mojom::GestureSourceType::kTouchInput,
params().from_devtools_debugger);
ForwardTouchInputEvents(timestamp, target);
break;
case SyntheticSmoothMoveGestureParams::MOUSE_DRAG_INPUT:
if (!synthetic_pointer_driver_)
synthetic_pointer_driver_ = SyntheticPointerDriver::Create(
content::mojom::GestureSourceType::kMouseInput,
params().from_devtools_debugger);
ForwardMouseClickInputEvents(timestamp, target);
break;
case SyntheticSmoothMoveGestureParams::MOUSE_WHEEL_INPUT:
ForwardMouseWheelInputEvents(timestamp, target);
// A mousewheel should not be able to close the WebContents.
CHECK(weak_controller);
break;
default:
return SyntheticGesture::GESTURE_SOURCE_TYPE_NOT_IMPLEMENTED;
}
if (!weak_controller) {
// A pointer gesture can cause the controller (and therefore `this`) to be
// synchronously deleted (e.g. clicking tab-close). Return immediately in
// this case.
return SyntheticGesture::GESTURE_ABORT;
}
return (state_ == DONE) ? SyntheticGesture::GESTURE_FINISHED
: SyntheticGesture::GESTURE_RUNNING;
}
// TODO(ssid): Clean up the switch statements by adding functions instead of
// large code, in the Forward*Events functions. Move the actions for all input
// types to different class (SyntheticInputDevice) which generates input events
// for all input types. The gesture class can use instance of device actions.
// Refer: crbug.com/461825
// CAUTION: forwarding a pointer press/release can cause `this` to be deleted.
void SyntheticSmoothMoveGesture::ForwardTouchInputEvents(
const base::TimeTicks& timestamp,
SyntheticGestureTarget* target) {
// Keep this on the stack so we can check if the forwarded event caused the
// deletion of the controller (which owns `this`).
base::WeakPtr<SyntheticGestureController> weak_controller =
dispatching_controller_;
switch (state_) {
case STARTED:
if (MoveIsNoOp()) {
state_ = DONE;
break;
}
if (params().add_slop) {
AddTouchSlopToFirstDistance(target);
}
ComputeNextMoveSegment();
PressPoint(target, timestamp);
if (!weak_controller) {
return;
}
state_ = MOVING;
break;
case MOVING: {
base::TimeTicks event_timestamp = ClampTimestamp(timestamp);
gfx::Vector2dF delta = GetPositionDeltaAtTime(event_timestamp);
MovePoint(target, delta, event_timestamp);
// A move should never be able to cause deletion of the controller.
CHECK(weak_controller);
if (FinishedCurrentMoveSegment(event_timestamp)) {
if (!IsLastMoveSegment()) {
current_move_segment_start_position_ +=
params().distances[current_move_segment_];
ComputeNextMoveSegment();
} else if (params().prevent_fling) {
state_ = STOPPING;
} else {
ReleasePoint(target, event_timestamp);
if (!weak_controller) {
return;
}
state_ = DONE;
}
}
} break;
case STOPPING:
if (timestamp - current_move_segment_stop_time_ >=
target->PointerAssumedStoppedTime()) {
base::TimeTicks event_timestamp = current_move_segment_stop_time_ +
target->PointerAssumedStoppedTime();
ReleasePoint(target, event_timestamp);
if (!weak_controller) {
return;
}
state_ = DONE;
}
break;
case SETUP:
NOTREACHED_IN_MIGRATION()
<< "State SETUP invalid for synthetic scroll using touch input.";
break;
case DONE:
NOTREACHED_IN_MIGRATION()
<< "State DONE invalid for synthetic scroll using touch input.";
break;
}
}
void SyntheticSmoothMoveGesture::ForwardMouseWheelInputEvents(
const base::TimeTicks& timestamp,
SyntheticGestureTarget* target) {
switch (state_) {
case STARTED:
if (MoveIsNoOp()) {
state_ = DONE;
break;
}
ComputeNextMoveSegment();
state_ = MOVING;
break;
case MOVING: {
base::TimeTicks event_timestamp = ClampTimestamp(timestamp);
gfx::Vector2dF delta = GetPositionDeltaAtTime(event_timestamp) -
current_move_segment_total_delta_;
if (delta.x() || delta.y()) {
blink::WebMouseWheelEvent::Phase phase =
needs_scroll_begin_ ? blink::WebMouseWheelEvent::kPhaseBegan
: blink::WebMouseWheelEvent::kPhaseChanged;
ForwardMouseWheelEvent(target, delta, phase, event_timestamp,
params().modifiers);
current_move_segment_total_delta_ += delta;
needs_scroll_begin_ = false;
}
if (FinishedCurrentMoveSegment(event_timestamp)) {
if (!IsLastMoveSegment()) {
current_move_segment_total_delta_ = gfx::Vector2dF();
ComputeNextMoveSegment();
} else {
state_ = DONE;
// Start flinging on the swipe action.
if (!params().prevent_fling && (params().fling_velocity_x != 0 ||
params().fling_velocity_y != 0)) {
ForwardFlingGestureEvent(
target, blink::WebGestureEvent::Type::kGestureFlingStart);
} else {
// Forward a wheel event with phase ended and zero deltas.
ForwardMouseWheelEvent(target, gfx::Vector2d(),
blink::WebMouseWheelEvent::kPhaseEnded,
event_timestamp, params().modifiers);
}
needs_scroll_begin_ = true;
}
}
} break;
case SETUP:
NOTREACHED_IN_MIGRATION()
<< "State SETUP invalid for synthetic scroll using mouse "
"wheel input.";
break;
case STOPPING:
NOTREACHED_IN_MIGRATION()
<< "State STOPPING invalid for synthetic scroll using mouse "
"wheel input.";
break;
case DONE:
NOTREACHED_IN_MIGRATION()
<< "State DONE invalid for synthetic scroll using mouse wheel input.";
break;
}
}
// CAUTION: forwarding a pointer press/release can cause `this` to be deleted.
void SyntheticSmoothMoveGesture::ForwardMouseClickInputEvents(
const base::TimeTicks& timestamp,
SyntheticGestureTarget* target) {
// Keep this on the stack so we can check if the forwarded event caused the
// deletion of the controller (which owns `this`).
base::WeakPtr<SyntheticGestureController> weak_controller =
dispatching_controller_;
switch (state_) {
case STARTED:
if (MoveIsNoOp()) {
state_ = DONE;
break;
}
ComputeNextMoveSegment();
PressPoint(target, timestamp);
if (!weak_controller) {
return;
}
state_ = MOVING;
break;
case MOVING: {
base::TimeTicks event_timestamp = ClampTimestamp(timestamp);
gfx::Vector2dF delta = GetPositionDeltaAtTime(event_timestamp);
MovePoint(target, delta, event_timestamp);
if (FinishedCurrentMoveSegment(event_timestamp)) {
if (!IsLastMoveSegment()) {
current_move_segment_start_position_ +=
params().distances[current_move_segment_];
ComputeNextMoveSegment();
} else {
ReleasePoint(target, event_timestamp);
if (!weak_controller) {
return;
}
state_ = DONE;
}
}
} break;
case STOPPING:
NOTREACHED_IN_MIGRATION()
<< "State STOPPING invalid for synthetic drag using mouse input.";
break;
case SETUP:
NOTREACHED_IN_MIGRATION()
<< "State SETUP invalid for synthetic drag using mouse input.";
break;
case DONE:
NOTREACHED_IN_MIGRATION()
<< "State DONE invalid for synthetic drag using mouse input.";
break;
}
}
void SyntheticSmoothMoveGesture::ForwardMouseWheelEvent(
SyntheticGestureTarget* target,
const gfx::Vector2dF& delta,
const blink::WebMouseWheelEvent::Phase phase,
const base::TimeTicks& timestamp,
int modifiers) const {
if (params().from_devtools_debugger) {
modifiers |= blink::WebInputEvent::kFromDebugger;
}
blink::WebMouseWheelEvent mouse_wheel_event =
blink::SyntheticWebMouseWheelEventBuilder::Build(
0, 0, delta.x(), delta.y(), modifiers, params().granularity);
mouse_wheel_event.SetPositionInWidget(
current_move_segment_start_position_.x(),
current_move_segment_start_position_.y());
mouse_wheel_event.phase = phase;
mouse_wheel_event.SetTimeStamp(timestamp);
target->DispatchInputEventToPlatform(mouse_wheel_event);
}
void SyntheticSmoothMoveGesture::ForwardFlingGestureEvent(
SyntheticGestureTarget* target,
const blink::WebInputEvent::Type type) const {
blink::WebGestureEvent fling_gesture_event =
blink::SyntheticWebGestureEventBuilder::Build(
type, blink::WebGestureDevice::kTouchpad);
fling_gesture_event.data.fling_start.velocity_x = params().fling_velocity_x;
fling_gesture_event.data.fling_start.velocity_y = params().fling_velocity_y;
fling_gesture_event.SetPositionInWidget(current_move_segment_start_position_);
target->DispatchInputEventToPlatform(fling_gesture_event);
}
void SyntheticSmoothMoveGesture::PressPoint(SyntheticGestureTarget* target,
const base::TimeTicks& timestamp) {
DCHECK_EQ(current_move_segment_, 0);
synthetic_pointer_driver_->Press(current_move_segment_start_position_.x(),
current_move_segment_start_position_.y());
synthetic_pointer_driver_->DispatchEvent(target, timestamp);
}
void SyntheticSmoothMoveGesture::MovePoint(SyntheticGestureTarget* target,
const gfx::Vector2dF& delta,
const base::TimeTicks& timestamp) {
DCHECK_GE(current_move_segment_, 0);
DCHECK_LT(current_move_segment_, static_cast<int>(params().distances.size()));
gfx::PointF new_position = current_move_segment_start_position_ + delta;
synthetic_pointer_driver_->Move(new_position.x(), new_position.y());
synthetic_pointer_driver_->DispatchEvent(target, timestamp);
}
void SyntheticSmoothMoveGesture::ReleasePoint(
SyntheticGestureTarget* target,
const base::TimeTicks& timestamp) {
DCHECK_EQ(current_move_segment_,
static_cast<int>(params().distances.size()) - 1);
gfx::PointF position;
if (params().input_type ==
SyntheticSmoothMoveGestureParams::MOUSE_DRAG_INPUT) {
position = current_move_segment_start_position_ +
GetPositionDeltaAtTime(timestamp);
}
synthetic_pointer_driver_->Release();
synthetic_pointer_driver_->DispatchEvent(target, timestamp);
}
void SyntheticSmoothMoveGesture::AddTouchSlopToFirstDistance(
SyntheticGestureTarget* target) {
DCHECK_GE(params().distances.size(), 1ul);
gfx::Vector2dF& first_move_distance = params().distances[0];
DCHECK_GT(first_move_distance.Length(), 0);
first_move_distance += ProjectScalarOntoVector(target->GetTouchSlopInDips(),
first_move_distance);
}
gfx::Vector2dF SyntheticSmoothMoveGesture::GetPositionDeltaAtTime(
const base::TimeTicks& timestamp) const {
// Make sure the final delta is correct. Using the computation below can lead
// to issues with floating point precision.
// TODO(bokan): This comment makes it sound like we have pixel perfect
// precision. In fact, gestures can accumulate a significant amount of
// error (e.g. due to snapping to physical pixels on each event).
if (FinishedCurrentMoveSegment(timestamp))
return params().distances[current_move_segment_];
return gfx::ScaleVector2d(
params().distances[current_move_segment_],
GetCurvedRatio(timestamp, current_move_segment_start_time_,
current_move_segment_stop_time_,
params().speed_in_pixels_s));
}
void SyntheticSmoothMoveGesture::ComputeNextMoveSegment() {
current_move_segment_++;
DCHECK_LT(current_move_segment_, static_cast<int>(params().distances.size()));
// Percentage based scrolls do not require velocity and are delivered in a
// single segment. No need to compute another segment
if (params().granularity == ui::ScrollGranularity::kScrollByPercentage) {
current_move_segment_start_time_ = current_move_segment_stop_time_;
} else {
const auto duration = base::Seconds(
double{params().distances[current_move_segment_].Length()} /
params().speed_in_pixels_s);
current_move_segment_start_time_ = current_move_segment_stop_time_;
current_move_segment_stop_time_ =
current_move_segment_start_time_ + duration;
}
}
base::TimeTicks SyntheticSmoothMoveGesture::ClampTimestamp(
const base::TimeTicks& timestamp) const {
return std::min(timestamp, current_move_segment_stop_time_);
}
bool SyntheticSmoothMoveGesture::FinishedCurrentMoveSegment(
const base::TimeTicks& timestamp) const {
return timestamp >= current_move_segment_stop_time_;
}
bool SyntheticSmoothMoveGesture::IsLastMoveSegment() const {
DCHECK_LT(current_move_segment_, static_cast<int>(params().distances.size()));
return current_move_segment_ ==
static_cast<int>(params().distances.size()) - 1;
}
bool SyntheticSmoothMoveGesture::MoveIsNoOp() const {
return params().distances.size() == 0 || params().distances[0].IsZero();
}
} // namespace content