Lomiri
InputDispatcherFilter.cpp
1 /*
2  * Copyright (C) 2016 Canonical Ltd.
3  *
4  * This program is free software: you can redistribute it and/or modify it under
5  * the terms of the GNU Lesser General Public License version 3, as published by
6  * the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranties of MERCHANTABILITY,
10  * SATISFACTORY QUALITY, or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11  * Lesser General Public License for more details.
12  *
13  * You should have received a copy of the GNU Lesser General Public License
14  * along with this program. If not, see <http://www.gnu.org/licenses/>.
15  */
16 
17 #include "InputDispatcherFilter.h"
18 #include "MousePointer.h"
19 
20 #include <QEvent>
21 #include <QGuiApplication>
22 #include <QQuickWindow>
23 #include <QScreen>
24 #include <QtMath>
25 #include <qpa/qplatformnativeinterface.h>
26 #include <qpa/qplatformscreen.h>
27 
28 InputDispatcherFilter *InputDispatcherFilter::instance()
29 {
30  static InputDispatcherFilter filter;
31  return &filter;
32 }
33 
34 InputDispatcherFilter::InputDispatcherFilter(QObject *parent)
35  : QObject(parent)
36  , m_pushing(false)
37 {
38  QPlatformNativeInterface *ni = QGuiApplication::platformNativeInterface();
39  m_inputDispatcher = static_cast<QObject*>(ni->nativeResourceForIntegration("InputDispatcher"));
40  if (m_inputDispatcher) {
41  m_inputDispatcher->installEventFilter(this);
42  }
43 }
44 
45 void InputDispatcherFilter::registerPointer(MousePointer *pointer)
46 {
47  // allow first registered pointer to be visible.
48  m_pointers.insert(pointer);
49 }
50 
51 void InputDispatcherFilter::unregisterPointer(MousePointer *pointer)
52 {
53  m_pointers.remove(pointer);
54 }
55 
56 bool InputDispatcherFilter::eventFilter(QObject *o, QEvent *e)
57 {
58  if (o != m_inputDispatcher) return false;
59 
60  switch (e->type()) {
61  case QEvent::MouseMove:
62  case QEvent::MouseButtonPress:
63  case QEvent::MouseButtonRelease:
64  {
65  // if we don't have any pointers, filter all mouse events.
66  auto pointer = currentPointer();
67  if (!pointer || !pointer->window()) return true;
68 
69  QMouseEvent* me = static_cast<QMouseEvent*>(e);
70 
71  // Local position gives relative change of mouse pointer.
72  QPointF movement = me->localPos();
73 
74  // Adjust the position
75  QPointF oldPos = pointer->window()->geometry().topLeft() + pointer->position();
76  QPointF newPos = adjustedPositionForMovement(oldPos, movement);
77 
78  QScreen* currentScreen = screenAt(newPos);
79  if (currentScreen) {
80  QRect screenRect = currentScreen->geometry();
81  qreal newX = (oldPos + movement).x();
82  qreal newY = (oldPos + movement).y();
83 
84  if (newX <= screenRect.left() && newY < screenRect.top() + pointer->topBoundaryOffset()) { // top left corner
85  const auto distance = qSqrt(qPow(newX, 2) + qPow(newY- screenRect.top() - pointer->topBoundaryOffset(), 2));
86  Q_EMIT pushedTopLeftCorner(currentScreen, qAbs(distance), me->buttons());
87  m_pushing = true;
88  } else if (newX >= screenRect.right()-1 && newY < screenRect.top() + pointer->topBoundaryOffset()) { // top right corner
89  const auto distance = qSqrt(qPow(newX-screenRect.right(), 2) + qPow(newY - screenRect.top() - pointer->topBoundaryOffset(), 2));
90  Q_EMIT pushedTopRightCorner(currentScreen, qAbs(distance), me->buttons());
91  m_pushing = true;
92  } else if (newX < 0 && newY >= screenRect.bottom()-1) { // bottom left corner
93  const auto distance = qSqrt(qPow(newX, 2) + qPow(newY-screenRect.bottom(), 2));
94  Q_EMIT pushedBottomLeftCorner(currentScreen, qAbs(distance), me->buttons());
95  m_pushing = true;
96  } else if (newX >= screenRect.right()-1 && newY >= screenRect.bottom()-1) { // bottom right corner
97  const auto distance = qSqrt(qPow(newX-screenRect.right(), 2) + qPow(newY-screenRect.bottom(), 2));
98  Q_EMIT pushedBottomRightCorner(currentScreen, qAbs(distance), me->buttons());
99  m_pushing = true;
100  } else if (newX < screenRect.left()) { // left edge
101  Q_EMIT pushedLeftBoundary(currentScreen, qAbs(newX), me->buttons());
102  m_pushing = true;
103  } else if (newX >= screenRect.right()) { // right edge
104  Q_EMIT pushedRightBoundary(currentScreen, newX - (screenRect.right() - 1), me->buttons());
105  m_pushing = true;
106  } else if (newY < screenRect.top() + pointer->topBoundaryOffset()) { // top edge
107  Q_EMIT pushedTopBoundary(currentScreen, qAbs(newY - screenRect.top() - pointer->topBoundaryOffset()), me->buttons());
108  m_pushing = true;
109  } else if (Q_LIKELY(newX > 0 && newX < screenRect.right()-1 && newY > 0 && newY < screenRect.bottom()-1)) { // normal pos, not pushing
110  if (m_pushing) {
111  Q_EMIT pushStopped(currentScreen);
112  m_pushing = false;
113  }
114  }
115  }
116 
117  // Send the event
118  QMouseEvent eCopy(me->type(), me->localPos(), newPos, me->button(), me->buttons(), me->modifiers());
119  eCopy.setTimestamp(me->timestamp());
120  o->event(&eCopy);
121  return true;
122  }
123  default:
124  break;
125  }
126  return false;
127 }
128 
129 QPointF InputDispatcherFilter::adjustedPositionForMovement(const QPointF &pt, const QPointF &movement) const
130 {
131  QPointF adjusted = pt + movement;
132 
133  auto screen = screenAt(adjusted); // first check if our move was to a screen with an enabled pointer.
134  if (screen) {
135  return adjusted;
136  } else if ((screen = screenAt(pt))) { // then check if our old position was valid
137  QRectF screenBounds = screen->geometry();
138  // bound the new position to the old screen geometry
139  adjusted.rx() = qMax(screenBounds.left(), qMin(adjusted.x(), screenBounds.right()-1));
140  adjusted.ry() = qMax(screenBounds.top(), qMin(adjusted.y(), screenBounds.bottom()-1));
141  } else {
142  auto screens = QGuiApplication::screens();
143 
144  // center of first screen with a pointer.
145  Q_FOREACH(QScreen* screen, screens) {
146  Q_FOREACH(MousePointer* pointer, m_pointers) {
147  if (pointer->isEnabled() && pointer->screen() == screen) {
148  return screen->geometry().center();
149  }
150  }
151  }
152  }
153  return adjusted;
154 }
155 
156 QScreen *InputDispatcherFilter::screenAt(const QPointF &pt) const
157 {
158  Q_FOREACH(MousePointer* pointer, m_pointers) {
159  if (!pointer->isEnabled()) continue;
160 
161  QScreen* screen = pointer->screen();
162  if (screen && screen->geometry().contains(pt.toPoint()))
163  return screen;
164  }
165  return nullptr;
166 }
167 
168 MousePointer *InputDispatcherFilter::currentPointer() const
169 {
170  Q_FOREACH(MousePointer* pointer, m_pointers) {
171  if (!pointer->isEnabled()) continue;
172  return pointer;
173  }
174  return nullptr;
175 }