plugins/Ubuntu/Gestures/TouchDispatcher.cpp · unity8

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unity8/plugins/Ubuntu/Gestures/TouchDispatcher.cpp

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1/*

3 *

4 * This program is free software; you can redistribute it and/or modify

5 * it under the terms of the GNU General Public License as published by

6 * the Free Software Foundation; version 3.

7 *

8 * This program is distributed in the hope that it will be useful,

9 * but WITHOUT ANY WARRANTY; without even the implied warranty of

10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

11 * GNU General Public License for more details.

12 *

13 * You should have received a copy of the GNU General Public License

14 * along with this program. If not, see <http://www.gnu.org/licenses/>.

15 */

17#include "TouchDispatcher.h"

19#include <QGuiApplication>

20#include <QScopedPointer>

21#include <QStyleHints>

23#pragma GCC diagnostic push

24#pragma GCC diagnostic ignored "-pedantic"

25#include <private/qquickitem_p.h>

26#pragma GCC diagnostic pop

28#define TOUCHDISPATCHER_DEBUG 0

30#if TOUCHDISPATCHER_DEBUG

31#include <DebugHelpers.h>

32#endif

34TouchDispatcher::TouchDispatcher()

35 : m_status(NoActiveTouch)

36 , m_touchMouseId(-1)

37 , m_touchMousePressTimestamp(0)

38{

39}

41void TouchDispatcher::setTargetItem(QQuickItem *target)

42{

43 if (target != m_targetItem) {

44 m_targetItem = target;

45 if (m_status != NoActiveTouch) {

46 qWarning("[TouchDispatcher] Changing target item in the middle of a touch stream");

47 m_status = TargetRejectedTouches;

48 }

49 }

50}

52void TouchDispatcher::dispatch(QEvent::Type eventType,

53 QTouchDevice *device,

54 Qt::KeyboardModifiers modifiers,

55 const QList<QTouchEvent::TouchPoint> &touchPoints,

56 QWindow *window,

57 ulong timestamp)

58{

59 if (m_targetItem.isNull()) {

60 qWarning("[TouchDispatcher] Cannot dispatch touch event because target item is null");

61 return;

62 }

64 if (eventType == QEvent::TouchBegin) {

65 dispatchTouchBegin(device, modifiers, touchPoints, window, timestamp);

67 } else if (eventType == QEvent::TouchUpdate || eventType == QEvent::TouchEnd) {

69 if (m_status == DeliveringTouchEvents) {

70 dispatchAsTouch(eventType, device, modifiers, touchPoints, window, timestamp);

71 } else if (m_status == DeliveringMouseEvents) {

72 dispatchAsMouse(device, modifiers, touchPoints, timestamp);

73 } else {

74 Q_ASSERT(m_status == TargetRejectedTouches);

75 #if TOUCHDISPATCHER_DEBUG

76 qDebug() << "[TouchDispatcher] Not dispatching touch event to" << m_targetItem.data()

77 << "because it already rejected the touch stream.";

78 #endif

79 // Do nothing

80 }

82 if (eventType == QEvent::TouchEnd) {

83 m_status = NoActiveTouch;

84 m_touchMouseId = -1;

85 }

87 } else {

88 // Should never happen

89 qCritical() << "[TouchDispatcher] Unexpected event type" << eventType;

90 Q_ASSERT(false);

91 return;

92 }

93}

95void TouchDispatcher::dispatchTouchBegin(

96 QTouchDevice *device,

97 Qt::KeyboardModifiers modifiers,

98 const QList<QTouchEvent::TouchPoint> &touchPoints,

99 QWindow *window,

100 ulong timestamp)

101{

102 Q_ASSERT(m_status == NoActiveTouch);

103 QQuickItem *targetItem = m_targetItem.data();

104

105 if (!targetItem->isEnabled() || !targetItem->isVisible()) {

106 #if TOUCHDISPATCHER_DEBUG

107 qDebug() << "[TouchDispatcher] Cannot dispatch touch event to" << targetItem

108 << "because it's disabled or invisible.";

109 #endif

110 return;

111 }

112

113 // Map touch points to targetItem coordinates

114 QList<QTouchEvent::TouchPoint> targetTouchPoints = touchPoints;

115 transformTouchPoints(targetTouchPoints, QQuickItemPrivate::get(targetItem)->windowToItemTransform());

116

117 QScopedPointer<QTouchEvent> touchEvent(

118 createQTouchEvent(QEvent::TouchBegin, device, modifiers, targetTouchPoints, window, timestamp));

119

120

121 #if TOUCHDISPATCHER_DEBUG

122 qDebug() << "[TouchDispatcher] dispatching" << qPrintable(touchEventToString(touchEvent.data()))

123 << "to" << targetItem;

124 #endif

125 QCoreApplication::sendEvent(targetItem, touchEvent.data());

126

127

128 if (touchEvent->isAccepted()) {

129 #if TOUCHDISPATCHER_DEBUG

130 qDebug() << "[TouchDispatcher] Item accepted the touch event.";

131 #endif

132 m_status = DeliveringTouchEvents;

133 } else if (targetItem->acceptedMouseButtons() & Qt::LeftButton) {

134 #if TOUCHDISPATCHER_DEBUG

135 qDebug() << "[TouchDispatcher] Item rejected the touch event. Trying a QMouseEvent";

136 #endif

137 // NB: Arbitrarily chose the first touch point to emulate the mouse pointer

138 QScopedPointer<QMouseEvent> mouseEvent(

139 touchToMouseEvent(QEvent::MouseButtonPress, targetTouchPoints.at(0), timestamp,

140 modifiers, false /* transformNeeded */));

141 Q_ASSERT(targetTouchPoints.at(0).state() == Qt::TouchPointPressed);

142

143 #if TOUCHDISPATCHER_DEBUG

144 qDebug() << "[TouchDispatcher] dispatching" << qPrintable(mouseEventToString(mouseEvent.data()))

145 << "to" << m_targetItem.data();

146 #endif

147 QCoreApplication::sendEvent(targetItem, mouseEvent.data());

148 if (mouseEvent->isAccepted()) {

149 #if TOUCHDISPATCHER_DEBUG

150 qDebug() << "[TouchDispatcher] Item accepted the QMouseEvent.";

151 #endif

152 m_status = DeliveringMouseEvents;

153 m_touchMouseId = targetTouchPoints.at(0).id();

154

155 if (checkIfDoubleClicked(timestamp)) {

156 QScopedPointer<QMouseEvent> doubleClickEvent(

157 touchToMouseEvent(QEvent::MouseButtonDblClick, targetTouchPoints.at(0), timestamp,

158 modifiers, false /* transformNeeded */));

159 #if TOUCHDISPATCHER_DEBUG

160 qDebug() << "[TouchDispatcher] dispatching" << qPrintable(mouseEventToString(doubleClickEvent.data()))

161 << "to" << m_targetItem.data();

162 #endif

163 QCoreApplication::sendEvent(targetItem, doubleClickEvent.data());

164 }

165

166 } else {

167 #if TOUCHDISPATCHER_DEBUG

168 qDebug() << "[TouchDispatcher] Item rejected the QMouseEvent.";

169 #endif

170 m_status = TargetRejectedTouches;

171 }

172 } else {

173 #if TOUCHDISPATCHER_DEBUG

174 qDebug() << "[TouchDispatcher] Item rejected the touch event and does not accept mouse buttons.";

175 #endif

176 m_status = TargetRejectedTouches;

177 }

178}

179

180void TouchDispatcher::dispatchAsTouch(QEvent::Type eventType,

181 QTouchDevice *device,

182 Qt::KeyboardModifiers modifiers,

183 const QList<QTouchEvent::TouchPoint> &touchPoints,

184 QWindow *window,

185 ulong timestamp)

186{

187 QQuickItem *targetItem = m_targetItem.data();

188

189 // Map touch points to targetItem coordinates

190 QList<QTouchEvent::TouchPoint> targetTouchPoints = touchPoints;

191 transformTouchPoints(targetTouchPoints, QQuickItemPrivate::get(targetItem)->windowToItemTransform());

192

193 QScopedPointer<QTouchEvent> eventForTargetItem(

194 createQTouchEvent(eventType, device, modifiers, targetTouchPoints, window, timestamp));

195

196

197 #if TOUCHDISPATCHER_DEBUG

198 qDebug() << "[TouchDispatcher] dispatching" << qPrintable(touchEventToString(eventForTargetItem.data()))

199 << "to" << targetItem;

200 #endif

201 QCoreApplication::sendEvent(targetItem, eventForTargetItem.data());

202}

203

204void TouchDispatcher::dispatchAsMouse(

205 QTouchDevice * /*device*/,

206 Qt::KeyboardModifiers modifiers,

207 const QList<QTouchEvent::TouchPoint> &touchPoints,

208 ulong timestamp)

209{

210 // TODO: Detect double clicks in order to synthesize QEvent::MouseButtonDblClick events accordingly

211

212 Q_ASSERT(!touchPoints.isEmpty());

213

214 const QTouchEvent::TouchPoint *touchMouse = nullptr;

215

216 if (m_touchMouseId != -1) {

217 for (int i = 0; i < touchPoints.count() && !touchMouse; ++i) {

218 const auto &touchPoint = touchPoints.at(i);

219 if (touchPoint.id() == m_touchMouseId) {

220 touchMouse = &touchPoint;

221 }

222 }

223

224 Q_ASSERT(touchMouse);

225 if (!touchMouse) {

226 // should not happen, but deal with it just in case.

227 qWarning("[TouchDispatcher] Didn't find touch with id %d, used for mouse pointer emulation.",

228 m_touchMouseId);

229 m_touchMouseId = touchPoints.at(0).id();

230 touchMouse = &touchPoints.at(0);

231 }

232 } else {

233 // Try to find a new touch for mouse emulation

234 for (int i = 0; i < touchPoints.count() && !touchMouse; ++i) {

235 const auto &touchPoint = touchPoints.at(i);

236 if (touchPoint.state() == Qt::TouchPointPressed) {

237 touchMouse = &touchPoint;

238 m_touchMouseId = touchMouse->id();

239 }

240 }

241 }

242

243 if (touchMouse) {

244 QEvent::Type eventType;

245 if (touchMouse->state() == Qt::TouchPointPressed) {

246 eventType = QEvent::MouseButtonPress;

247 } if (touchMouse->state() == Qt::TouchPointReleased) {

248 eventType = QEvent::MouseButtonRelease;

249 m_touchMouseId = -1;

250 } else {

251 eventType = QEvent::MouseMove;

252 }

253

254 QScopedPointer<QMouseEvent> mouseEvent(touchToMouseEvent(eventType, *touchMouse, timestamp, modifiers,

255 true /* transformNeeded */));

256

257 #if TOUCHDISPATCHER_DEBUG

258 qDebug() << "[TouchDispatcher] dispatching" << qPrintable(mouseEventToString(mouseEvent.data()))

259 << "to" << m_targetItem.data();

260 #endif

261 QCoreApplication::sendEvent(m_targetItem.data(), mouseEvent.data());

262 }

263}

264

265QTouchEvent *TouchDispatcher::createQTouchEvent(QEvent::Type eventType,

266 QTouchDevice *device,

267 Qt::KeyboardModifiers modifiers,

268 const QList<QTouchEvent::TouchPoint> &touchPoints,

269 QWindow *window,

270 ulong timestamp)

271{

272 Qt::TouchPointStates eventStates = 0;

273 for (int i = 0; i < touchPoints.count(); i++)

274 eventStates |= touchPoints[i].state();

275 // if all points have the same state, set the event type accordingly

276 switch (eventStates) {

277 case Qt::TouchPointPressed:

278 eventType = QEvent::TouchBegin;

279 break;

280 case Qt::TouchPointReleased:

281 eventType = QEvent::TouchEnd;

282 break;

283 default:

284 eventType = QEvent::TouchUpdate;

285 break;

286 }

287

288 QTouchEvent *touchEvent = new QTouchEvent(eventType);

289 touchEvent->setWindow(window);

290 touchEvent->setTarget(m_targetItem.data());

291 touchEvent->setDevice(device);

292 touchEvent->setModifiers(modifiers);

293 touchEvent->setTouchPoints(touchPoints);

294 touchEvent->setTouchPointStates(eventStates);

295 touchEvent->setTimestamp(timestamp);

296 touchEvent->accept();

297 return touchEvent;

298}

299

300// NB: From QQuickWindow

301void TouchDispatcher::transformTouchPoints(QList<QTouchEvent::TouchPoint> &touchPoints, const QTransform &transform)

302{

303 QMatrix4x4 transformMatrix(transform);

304 for (int i=0; i<touchPoints.count(); i++) {

305 QTouchEvent::TouchPoint &touchPoint = touchPoints[i];

306 touchPoint.setRect(transform.mapRect(touchPoint.sceneRect()));

307 touchPoint.setStartPos(transform.map(touchPoint.startScenePos()));

308 touchPoint.setLastPos(transform.map(touchPoint.lastScenePos()));

309 touchPoint.setVelocity(transformMatrix.mapVector(touchPoint.velocity()).toVector2D());

310 }

311}

312

313// Copied with minor modifications from qtdeclarative/src/quick/items/qquickwindow.cpp

314QMouseEvent *TouchDispatcher::touchToMouseEvent(

315 QEvent::Type type, const QTouchEvent::TouchPoint &p,

316 ulong timestamp, Qt::KeyboardModifiers modifiers,

317 bool transformNeeded)

318{

319 QQuickItem *item = m_targetItem.data();

320

321 // The touch point local position and velocity are not yet transformed.

322 QMouseEvent *me = new QMouseEvent(type, transformNeeded ? item->mapFromScene(p.scenePos()) : p.pos(),

323 p.scenePos(), p.screenPos(), Qt::LeftButton,

324 (type == QEvent::MouseButtonRelease ? Qt::NoButton : Qt::LeftButton),

325 modifiers);

326 me->setAccepted(true);

327 me->setTimestamp(timestamp);

328 QVector2D transformedVelocity = p.velocity();

329 if (transformNeeded) {

330 QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(item);

331 QMatrix4x4 transformMatrix(itemPrivate->windowToItemTransform());

332 transformedVelocity = transformMatrix.mapVector(p.velocity()).toVector2D();

333 }

334

335 // Add these later if needed:

336 //QGuiApplicationPrivate::setMouseEventCapsAndVelocity(me, event->device()->capabilities(), transformedVelocity);

337 //QGuiApplicationPrivate::setMouseEventSource(me, Qt::MouseEventSynthesizedByQt);

338 return me;

339}

340

341/*

342 Copied from qquickwindow.cpp which has:

344 Under GPL 3.0 license.

345*/

346bool TouchDispatcher::checkIfDoubleClicked(ulong newPressEventTimestamp)

347{

348 bool doubleClicked;

349

350 if (m_touchMousePressTimestamp == 0) {

351 // just initialize the variable

352 m_touchMousePressTimestamp = newPressEventTimestamp;

353 doubleClicked = false;

354 } else {

355 ulong timeBetweenPresses = newPressEventTimestamp - m_touchMousePressTimestamp;

356 ulong doubleClickInterval = static_cast<ulong>(qApp->styleHints()->

357 mouseDoubleClickInterval());

358 doubleClicked = timeBetweenPresses < doubleClickInterval;

359 if (doubleClicked) {

360 m_touchMousePressTimestamp = 0;

361 } else {

362 m_touchMousePressTimestamp = newPressEventTimestamp;

363 }

364 }

365

366 return doubleClicked;

367}