src/kitemviews/private/ktwofingerswipe.cpp

   1 /*
   2  * SPDX-FileCopyrightText: 2020 Steffen Hartleib <steffenhartleib@t-online.de>
   3  *
   4  * SPDX-License-Identifier: GPL-2.0-or-later
   5  */
   6
   7 // Self
   8 #include "ktwofingerswipe.h"
   9
  10 // Qt
  11 #include <QTouchEvent>
  12 #include <QLineF>
  13
  14 KTwoFingerSwipeRecognizer::KTwoFingerSwipeRecognizer() :
  15     QGestureRecognizer(),
  16     m_touchBeginnTimestamp(0),
  17     m_gestureAlreadyTriggered(false)
  18 {
  19 }
  20
  21 KTwoFingerSwipeRecognizer::~KTwoFingerSwipeRecognizer()
  22 {
  23 }
  24
  25 QGesture* KTwoFingerSwipeRecognizer::create(QObject*)
  26 {
  27     return static_cast<QGesture*>(new KTwoFingerSwipe());
  28 }
  29
  30 QGestureRecognizer::Result KTwoFingerSwipeRecognizer::recognize(QGesture* gesture, QObject* watched, QEvent* event)
  31 {
  32     Q_UNUSED(watched)
  33
  34     KTwoFingerSwipe* const kTwoFingerSwipe = static_cast<KTwoFingerSwipe*>(gesture);
  35     const QTouchEvent* touchEvent = static_cast<const QTouchEvent*>(event);
  36
  37     const int maxTimeFrameForSwipe = 90;
  38     const int minDistanceForSwipe = 30;
  39
  40     switch (event->type()) {
  41     case QEvent::TouchBegin: {
  42         m_touchBeginnTimestamp = touchEvent->timestamp();
  43         m_gestureAlreadyTriggered = false;
  44         kTwoFingerSwipe->setHotSpot(touchEvent->touchPoints().first().startScreenPos());
  45         kTwoFingerSwipe->setPos(touchEvent->touchPoints().first().startPos());
  46         kTwoFingerSwipe->setScreenPos(touchEvent->touchPoints().first().startScreenPos());
  47         kTwoFingerSwipe->setScenePos(touchEvent->touchPoints().first().startScenePos());
  48         return MayBeGesture;
  49     }
  50
  51     case QEvent::TouchUpdate: {
  52         const qint64 now = touchEvent->timestamp();
  53         const qint64 elapsedTime = now - m_touchBeginnTimestamp;
  54         const QPointF distance = touchEvent->touchPoints().first().startPos() - touchEvent->touchPoints().first().pos();
  55         kTwoFingerSwipe->setHotSpot(touchEvent->touchPoints().first().startScreenPos());
  56         kTwoFingerSwipe->setPos(touchEvent->touchPoints().first().startPos());
  57         kTwoFingerSwipe->setScreenPos(touchEvent->touchPoints().first().startScreenPos());
  58         kTwoFingerSwipe->setScenePos(touchEvent->touchPoints().first().startScenePos());
  59         const QLineF ql = QLineF(touchEvent->touchPoints().first().startPos(), touchEvent->touchPoints().first().pos());
  60         kTwoFingerSwipe->setSwipeAngle(ql.angle());
  61
  62         if (touchEvent->touchPoints().size() > 2) {
  63             return CancelGesture;
  64         }
  65
  66         if (touchEvent->touchPoints().size() == 2) {
  67             if ((elapsedTime) > maxTimeFrameForSwipe) {
  68                 return CancelGesture;
  69             }
  70
  71             if (distance.manhattanLength() >= minDistanceForSwipe &&
  72                     (elapsedTime) <= maxTimeFrameForSwipe && !m_gestureAlreadyTriggered) {
  73                 m_gestureAlreadyTriggered = true;
  74                 return FinishGesture;
  75             } else if ((elapsedTime) <= maxTimeFrameForSwipe && !m_gestureAlreadyTriggered) {
  76                 return TriggerGesture;
  77             }
  78         }
  79         break;
  80     }
  81
  82     default:
  83         return Ignore;
  84     }
  85     return Ignore;
  86 }
  87
  88 KTwoFingerSwipe::KTwoFingerSwipe(QObject* parent) :
  89     QGesture(parent),
  90     m_pos(QPointF(-1, -1)),
  91     m_screenPos(QPointF(-1, -1)),
  92     m_scenePos(QPointF(-1, -1)),
  93     m_swipeAngle(0.0)
  94 {
  95 }
  96
  97 KTwoFingerSwipe::~KTwoFingerSwipe()
  98 {
  99 }
 100
 101 QPointF KTwoFingerSwipe::pos() const
 102 {
 103     return m_pos;
 104 }
 105
 106 void KTwoFingerSwipe::setPos(QPointF _pos)
 107 {
 108     m_pos = _pos;
 109 }
 110
 111 QPointF KTwoFingerSwipe::screenPos() const
 112 {
 113     return m_screenPos;
 114 }
 115
 116 void KTwoFingerSwipe::setScreenPos(QPointF _screenPos)
 117 {
 118     m_screenPos = _screenPos;
 119 }
 120
 121 QPointF KTwoFingerSwipe::scenePos() const
 122 {
 123     return m_scenePos;
 124 }
 125
 126 void KTwoFingerSwipe::setScenePos(QPointF _scenePos)
 127 {
 128     m_scenePos = _scenePos;
 129 }
 130
 131 qreal KTwoFingerSwipe::swipeAngle() const
 132 {
 133     return m_swipeAngle;
 134 }
 135  void KTwoFingerSwipe::setSwipeAngle(qreal _swipeAngle)
 136 {
 137     m_swipeAngle = _swipeAngle;
 138 }
 139