1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
|
// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <stdint.h>
#include "base/functional/callback.h"
#include "content/common/input/input_injector.mojom.h"
#include "content/common/input/synthetic_touchpad_pinch_gesture.h"
#include "third_party/blink/public/common/input/synthetic_web_input_event_builders.h"
namespace content {
namespace {
float Lerp(float start, float end, float progress) {
return start + progress * (end - start);
}
} // namespace
SyntheticTouchpadPinchGesture::SyntheticTouchpadPinchGesture(
const SyntheticPinchGestureParams& gesture_params)
: SyntheticGestureBase(gesture_params),
gesture_source_type_(content::mojom::GestureSourceType::kDefaultInput),
state_(SETUP),
current_scale_(1.0f) {
CHECK_EQ(SyntheticGestureParams::PINCH_GESTURE,
gesture_params.GetGestureType());
DCHECK_GT(params().scale_factor, 0.0f);
if (params().gesture_source_type !=
content::mojom::GestureSourceType::kTouchpadInput) {
DCHECK_EQ(params().gesture_source_type,
content::mojom::GestureSourceType::kDefaultInput);
params().gesture_source_type =
content::mojom::GestureSourceType::kTouchpadInput;
}
}
SyntheticTouchpadPinchGesture::~SyntheticTouchpadPinchGesture() {}
SyntheticGesture::Result SyntheticTouchpadPinchGesture::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) {
gesture_source_type_ = params().gesture_source_type;
if (gesture_source_type_ ==
content::mojom::GestureSourceType::kDefaultInput)
gesture_source_type_ = target->GetDefaultSyntheticGestureSourceType();
state_ = STARTED;
start_time_ = timestamp;
}
DCHECK_NE(gesture_source_type_,
content::mojom::GestureSourceType::kDefaultInput);
if (gesture_source_type_ == content::mojom::GestureSourceType::kMouseInput) {
ForwardGestureEvents(timestamp, target);
// A pinch gesture cannot cause `this` to be destroyed.
CHECK(weak_controller);
} else {
// Touch input should be using SyntheticTouchscreenPinchGesture.
return SyntheticGesture::GESTURE_SOURCE_TYPE_NOT_IMPLEMENTED;
}
return (state_ == DONE) ? SyntheticGesture::GESTURE_FINISHED
: SyntheticGesture::GESTURE_RUNNING;
}
void SyntheticTouchpadPinchGesture::WaitForTargetAck(
base::OnceClosure callback,
SyntheticGestureTarget* target) const {
target->WaitForTargetAck(params().GetGestureType(), gesture_source_type_,
std::move(callback));
}
void SyntheticTouchpadPinchGesture::ForwardGestureEvents(
const base::TimeTicks& timestamp,
SyntheticGestureTarget* target) {
switch (state_) {
case STARTED:
// Check for an early finish.
if (params().scale_factor == 1.0f) {
state_ = DONE;
break;
}
CalculateEndTime(target);
// Send the start event.
target->DispatchInputEventToPlatform(
blink::SyntheticWebGestureEventBuilder::Build(
blink::WebGestureEvent::Type::kGesturePinchBegin,
blink::WebGestureDevice::kTouchpad,
params().from_devtools_debugger
? blink::WebInputEvent::kFromDebugger
: blink::WebInputEvent::kNoModifiers));
state_ = IN_PROGRESS;
break;
case IN_PROGRESS: {
base::TimeTicks event_timestamp = ClampTimestamp(timestamp);
float target_scale = CalculateTargetScale(event_timestamp);
float incremental_scale = target_scale / current_scale_;
current_scale_ = target_scale;
// Send the incremental scale event.
target->DispatchInputEventToPlatform(
blink::SyntheticWebGestureEventBuilder::BuildPinchUpdate(
incremental_scale, params().anchor.x(), params().anchor.y(),
params().from_devtools_debugger
? blink::WebInputEvent::kFromDebugger
: blink::WebInputEvent::kNoModifiers,
blink::WebGestureDevice::kTouchpad));
if (HasReachedTarget(event_timestamp)) {
target->DispatchInputEventToPlatform(
blink::SyntheticWebGestureEventBuilder::Build(
blink::WebGestureEvent::Type::kGesturePinchEnd,
blink::WebGestureDevice::kTouchpad,
params().from_devtools_debugger
? blink::WebInputEvent::kFromDebugger
: blink::WebInputEvent::kNoModifiers));
state_ = DONE;
}
break;
}
case SETUP:
NOTREACHED() << "State SETUP invalid for synthetic pinch.";
case DONE:
NOTREACHED() << "State DONE invalid for synthetic pinch.";
}
}
float SyntheticTouchpadPinchGesture::CalculateTargetScale(
const base::TimeTicks& timestamp) const {
// Make sure the final delta is correct. Using the computation below can lead
// to issues with floating point precision.
if (HasReachedTarget(timestamp))
return params().scale_factor;
const float progress = (timestamp - start_time_) / (stop_time_ - start_time_);
return Lerp(1.0f, params().scale_factor, progress);
}
// Calculate an end time based on the amount of scaling to be done and the
// |relative_pointer_speed_in_pixels_s|. Because we don't have an actual pixel
// delta, we assume that a pinch of 200 pixels is needed to double the screen
// size and generate a stop time based on that.
// TODO(ericrk): We should not calculate duration from
// |relative_pointer_speed_in_pixels_s|, but should instead get a duration from
// a SyntheticTouchpadPinchGestureParams type. crbug.com/534976
void SyntheticTouchpadPinchGesture::CalculateEndTime(
SyntheticGestureTarget* target) {
const int kPixelsNeededToDoubleOrHalve = 200;
float scale_factor = params().scale_factor;
if (scale_factor < 1.0f) {
// If we are scaling down, calculate the time based on the inverse so that
// halving or doubling the scale takes the same amount of time.
scale_factor = 1.0f / scale_factor;
}
float scale_factor_delta =
(scale_factor - 1.0f) * kPixelsNeededToDoubleOrHalve;
const base::TimeDelta total_duration = base::Seconds(
scale_factor_delta / params().relative_pointer_speed_in_pixels_s);
DCHECK_GT(total_duration, base::TimeDelta());
stop_time_ = start_time_ + total_duration;
}
base::TimeTicks SyntheticTouchpadPinchGesture::ClampTimestamp(
const base::TimeTicks& timestamp) const {
return std::min(timestamp, stop_time_);
}
bool SyntheticTouchpadPinchGesture::HasReachedTarget(
const base::TimeTicks& timestamp) const {
return timestamp >= stop_time_;
}
} // namespace content
|
