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fl_scrolling_manager.cc
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1 // Copyright 2013 The Flutter Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "flutter/shell/platform/linux/fl_scrolling_manager.h"
6
7 static constexpr int kMicrosecondsPerMillisecond = 1000;
8
9 struct _FlScrollingManager {
10 GObject parent_instance;
11
12 FlScrollingViewDelegate* view_delegate;
13
14 gdouble last_x;
15 gdouble last_y;
16
17 gboolean pan_started;
18 gdouble pan_x;
19 gdouble pan_y;
20
21 gboolean zoom_started;
22 gboolean rotate_started;
23 gdouble scale;
24 gdouble rotation;
25 };
26
27 G_DEFINE_TYPE(FlScrollingManager, fl_scrolling_manager, G_TYPE_OBJECT);
28
29 static void fl_scrolling_manager_dispose(GObject* object) {
30 FlScrollingManager* self = FL_SCROLLING_MANAGER(object);
31
32 if (self->view_delegate != nullptr) {
33 g_object_remove_weak_pointer(
34 object, reinterpret_cast<gpointer*>(&self->view_delegate));
35 self->view_delegate = nullptr;
36 }
37
38 G_OBJECT_CLASS(fl_scrolling_manager_parent_class)->dispose(object);
39 }
40
41 static void fl_scrolling_manager_class_init(FlScrollingManagerClass* klass) {
42 G_OBJECT_CLASS(klass)->dispose = fl_scrolling_manager_dispose;
43 }
44
45 static void fl_scrolling_manager_init(FlScrollingManager* self) {}
46
47 FlScrollingManager* fl_scrolling_manager_new(
48 FlScrollingViewDelegate* view_delegate) {
49 g_return_val_if_fail(FL_IS_SCROLLING_VIEW_DELEGATE(view_delegate), nullptr);
50
51 FlScrollingManager* self = FL_SCROLLING_MANAGER(
52 g_object_new(fl_scrolling_manager_get_type(), nullptr));
53
54 self->view_delegate = view_delegate;
55 g_object_add_weak_pointer(
56 G_OBJECT(view_delegate),
57 reinterpret_cast<gpointer*>(&(self->view_delegate)));
58
59 self->pan_started = FALSE;
60 self->zoom_started = FALSE;
61 self->rotate_started = FALSE;
62
63 return self;
64 }
65
66 void fl_scrolling_manager_set_last_mouse_position(FlScrollingManager* self,
67 gdouble x,
68 gdouble y) {
69 g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
70 self->last_x = x;
71 self->last_y = y;
72 }
73
74 void fl_scrolling_manager_handle_scroll_event(FlScrollingManager* self,
75 GdkEventScroll* scroll_event,
76 gint scale_factor) {
77 g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
78
79 GdkEvent* event = reinterpret_cast<GdkEvent*>(scroll_event);
80
81 guint event_time = gdk_event_get_time(event);
82 gdouble event_x = 0.0, event_y = 0.0;
83 gdk_event_get_coords(event, &event_x, &event_y);
84 gdouble scroll_delta_x = 0.0, scroll_delta_y = 0.0;
85 GdkScrollDirection event_direction = GDK_SCROLL_SMOOTH;
86 if (gdk_event_get_scroll_direction(event, &event_direction)) {
87 if (event_direction == GDK_SCROLL_UP) {
88 scroll_delta_x = 0;
89 scroll_delta_y = -1;
90 } else if (event_direction == GDK_SCROLL_DOWN) {
91 scroll_delta_x = 0;
92 scroll_delta_y = 1;
93 } else if (event_direction == GDK_SCROLL_LEFT) {
94 scroll_delta_x = -1;
95 scroll_delta_y = 0;
96 } else if (event_direction == GDK_SCROLL_RIGHT) {
97 scroll_delta_x = 1;
98 scroll_delta_y = 0;
99 }
100 } else {
101 gdk_event_get_scroll_deltas(event, &scroll_delta_x, &scroll_delta_y);
102 }
103
104 // The multiplier is taken from the Chromium source
105 // (ui/events/x/events_x_utils.cc).
106 const int kScrollOffsetMultiplier = 53;
107 scroll_delta_x *= kScrollOffsetMultiplier * scale_factor;
108 scroll_delta_y *= kScrollOffsetMultiplier * scale_factor;
109
110 if (gdk_device_get_source(gdk_event_get_source_device(event)) ==
111 GDK_SOURCE_TOUCHPAD) {
112 scroll_delta_x *= -1;
113 scroll_delta_y *= -1;
114 if (gdk_event_is_scroll_stop_event(event)) {
115 fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
116 self->view_delegate, event_time * kMicrosecondsPerMillisecond,
117 event_x * scale_factor, event_y * scale_factor, kPanZoomEnd,
118 self->pan_x, self->pan_y, 0, 0);
119 self->pan_started = FALSE;
120 } else {
121 if (!self->pan_started) {
122 self->pan_x = 0;
123 self->pan_y = 0;
124 fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
125 self->view_delegate, event_time * kMicrosecondsPerMillisecond,
126 event_x * scale_factor, event_y * scale_factor, kPanZoomStart, 0, 0,
127 0, 0);
128 self->pan_started = TRUE;
129 }
130 self->pan_x += scroll_delta_x;
131 self->pan_y += scroll_delta_y;
132 fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
133 self->view_delegate, event_time * kMicrosecondsPerMillisecond,
134 event_x * scale_factor, event_y * scale_factor, kPanZoomUpdate,
135 self->pan_x, self->pan_y, 1, 0);
136 }
137 } else {
138 self->last_x = event_x * scale_factor;
139 self->last_y = event_y * scale_factor;
140 fl_scrolling_view_delegate_send_mouse_pointer_event(
141 self->view_delegate,
142 FlutterPointerPhase::kMove /* arbitrary value, phase will be ignored as
143 this is a discrete scroll event */
144 ,
145 event_time * kMicrosecondsPerMillisecond, event_x * scale_factor,
146 event_y * scale_factor, kFlutterPointerDeviceKindMouse, scroll_delta_x,
147 scroll_delta_y, 0);
148 }
149 }
150
151 void fl_scrolling_manager_handle_rotation_begin(FlScrollingManager* self) {
152 g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
153
154 self->rotate_started = TRUE;
155 if (!self->zoom_started) {
156 self->scale = 1;
157 self->rotation = 0;
158 fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
159 self->view_delegate, g_get_real_time(), self->last_x, self->last_y,
160 kPanZoomStart, 0, 0, 0, 0);
161 }
162 }
163
164 void fl_scrolling_manager_handle_rotation_update(FlScrollingManager* self,
165 gdouble rotation) {
166 g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
167
168 self->rotation = rotation;
169 fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
170 self->view_delegate, g_get_real_time(), self->last_x, self->last_y,
171 kPanZoomUpdate, 0, 0, self->scale, self->rotation);
172 }
173
174 void fl_scrolling_manager_handle_rotation_end(FlScrollingManager* self) {
175 g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
176
177 self->rotate_started = FALSE;
178 if (!self->zoom_started) {
179 fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
180 self->view_delegate, g_get_real_time(), self->last_x, self->last_y,
181 kPanZoomEnd, 0, 0, 0, 0);
182 }
183 }
184
185 void fl_scrolling_manager_handle_zoom_begin(FlScrollingManager* self) {
186 g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
187
188 self->zoom_started = TRUE;
189 if (!self->rotate_started) {
190 self->scale = 1;
191 self->rotation = 0;
192 fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
193 self->view_delegate, g_get_real_time(), self->last_x, self->last_y,
194 kPanZoomStart, 0, 0, 0, 0);
195 }
196 }
197
198 void fl_scrolling_manager_handle_zoom_update(FlScrollingManager* self,
199 gdouble scale) {
200 g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
201
202 self->scale = scale;
203 fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
204 self->view_delegate, g_get_real_time(), self->last_x, self->last_y,
205 kPanZoomUpdate, 0, 0, self->scale, self->rotation);
206 }
207
208 void fl_scrolling_manager_handle_zoom_end(FlScrollingManager* self) {
209 g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
210
211 self->zoom_started = FALSE;
212 if (!self->rotate_started) {
213 fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
214 self->view_delegate, g_get_real_time(), self->last_x, self->last_y,
215 kPanZoomEnd, 0, 0, 0, 0);
216 }
217 }
event
FlKeyEvent * event
Definition: fl_key_channel_responder.cc:118
_FlScrollingManager
Definition: fl_scrolling_manager.cc:9
fl_scrolling_manager_handle_zoom_end
void fl_scrolling_manager_handle_zoom_end(FlScrollingManager *self)
Definition: fl_scrolling_manager.cc:208
fl_scrolling_manager_handle_scroll_event
void fl_scrolling_manager_handle_scroll_event(FlScrollingManager *self, GdkEventScroll *scroll_event, gint scale_factor)
Definition: fl_scrolling_manager.cc:74
_FlScrollingManager::pan_x
gdouble pan_x
Definition: fl_scrolling_manager.cc:18
_FlScrollingManager::pan_y
gdouble pan_y
Definition: fl_scrolling_manager.cc:19
_FlScrollingManager::zoom_started
gboolean zoom_started
Definition: fl_scrolling_manager.cc:21
fl_scrolling_manager_class_init
static void fl_scrolling_manager_class_init(FlScrollingManagerClass *klass)
Definition: fl_scrolling_manager.cc:41
G_DEFINE_TYPE
G_DEFINE_TYPE(FlScrollingManager, fl_scrolling_manager, G_TYPE_OBJECT)
fl_scrolling_manager_dispose
static void fl_scrolling_manager_dispose(GObject *object)
Definition: fl_scrolling_manager.cc:29
fl_scrolling_manager_new
FlScrollingManager * fl_scrolling_manager_new(FlScrollingViewDelegate *view_delegate)
Definition: fl_scrolling_manager.cc:47
_FlScrollingManager::scale
gdouble scale
Definition: fl_scrolling_manager.cc:23
fl_scrolling_manager_set_last_mouse_position
void fl_scrolling_manager_set_last_mouse_position(FlScrollingManager *self, gdouble x, gdouble y)
Definition: fl_scrolling_manager.cc:66
fl_scrolling_view_delegate_send_mouse_pointer_event
void fl_scrolling_view_delegate_send_mouse_pointer_event(FlScrollingViewDelegate *self, FlutterPointerPhase phase, size_t timestamp, double x, double y, FlutterPointerDeviceKind device_kind, double scroll_delta_x, double scroll_delta_y, int64_t buttons)
Definition: fl_scrolling_view_delegate.cc:14
_FlScrollingManager::pan_started
gboolean pan_started
Definition: fl_scrolling_manager.cc:17
_FlScrollingManager::rotation
gdouble rotation
Definition: fl_scrolling_manager.cc:24
fl_scrolling_manager.h
TRUE
return TRUE
Definition: fl_pixel_buffer_texture_test.cc:53
fl_scrolling_manager_handle_zoom_update
void fl_scrolling_manager_handle_zoom_update(FlScrollingManager *self, gdouble scale)
Definition: fl_scrolling_manager.cc:198
_FlScrollingManager::view_delegate
FlScrollingViewDelegate * view_delegate
Definition: fl_scrolling_manager.cc:12
fl_scrolling_manager_init
static void fl_scrolling_manager_init(FlScrollingManager *self)
Definition: fl_scrolling_manager.cc:45
fl_scrolling_manager_handle_rotation_update
void fl_scrolling_manager_handle_rotation_update(FlScrollingManager *self, gdouble rotation)
Definition: fl_scrolling_manager.cc:164
_FlScrollingManager::parent_instance
GObject parent_instance
Definition: fl_scrolling_manager.cc:10
_FlScrollingManager::last_x
gdouble last_x
Definition: fl_scrolling_manager.cc:14
_FlScrollingManager::rotate_started
gboolean rotate_started
Definition: fl_scrolling_manager.cc:22
kMicrosecondsPerMillisecond
static constexpr int kMicrosecondsPerMillisecond
Definition: fl_scrolling_manager.cc:7
fl_scrolling_manager_handle_rotation_end
void fl_scrolling_manager_handle_rotation_end(FlScrollingManager *self)
Definition: fl_scrolling_manager.cc:174
fl_scrolling_manager_handle_rotation_begin
void fl_scrolling_manager_handle_rotation_begin(FlScrollingManager *self)
Definition: fl_scrolling_manager.cc:151
_FlScrollingManager::last_y
gdouble last_y
Definition: fl_scrolling_manager.cc:15
fl_scrolling_manager_handle_zoom_begin
void fl_scrolling_manager_handle_zoom_begin(FlScrollingManager *self)
Definition: fl_scrolling_manager.cc:185
fl_scrolling_view_delegate_send_pointer_pan_zoom_event
void fl_scrolling_view_delegate_send_pointer_pan_zoom_event(FlScrollingViewDelegate *self, size_t timestamp, double x, double y, FlutterPointerPhase phase, double pan_x, double pan_y, double scale, double rotation)
Definition: fl_scrolling_view_delegate.cc:30