Warning, file /office/calligra/libs/widgetutils/KoKineticScroller.cpp was not indexed or was modified since last indexation (in which case cross-reference links may be missing, inaccurate or erroneous).

 /* This file is part of the KDE project
  * Copyright (C) 2018 Emmet O'Neill <emmetoneill.pdx@gmail.com>
  * Copyright (C) 2018 Eoin O'Neill <eoinoneill1991@gmail.com>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */
 
 #include <KoKineticScroller.h>
 #include <QAbstractItemView>
 #include <ksharedconfig.h>
 #include <kconfiggroup.h>
 
 QScroller* KoKineticScroller::createPreconfiguredScroller(QAbstractScrollArea *scrollArea)
 {
     KConfigGroup config = KSharedConfig::openConfig()->group("KoKineticScroller");
     int sensitivity = config.readEntry("KineticScrollingSensitivity", 75);
     bool enabled = config.readEntry("KineticScrollingEnabled", true);
     bool hideScrollBars = config.readEntry("KineticScrollingHideScrollbar", false);
     float resistanceCoefficient = config.readEntry("KineticScrollingResistanceCoefficient", 10.0f);
     float dragVelocitySmoothFactor = config.readEntry("KineticScrollingDragVelocitySmoothingFactor", 1.0f);
     float minimumVelocity = config.readEntry("KineticScrollingMinimumVelocity", 0.0f);
     float axisLockThresh = config.readEntry("KineticScrollingAxisLockThreshold", 1.0f);
     float maximumClickThroughVelocity = config.readEntry("KineticScrollingMaxClickThroughVelocity", 0.0f);
     float flickAccelerationFactor = config.readEntry("KineticScrollingFlickAccelerationFactor", 1.5f);
     float overshootDragResistanceFactor = config.readEntry("KineticScrollingOvershotDragResistanceFactor", 0.1f);
     float overshootDragDistanceFactor = config.readEntry("KineticScrollingOvershootDragDistanceFactor", 0.3f);
     float overshootScrollDistanceFactor = config.readEntry("KineticScrollingOvershootScrollDistanceFactor", 0.1f);
     float overshootScrollTime = config.readEntry("KineticScrollingOvershootScrollTime", 0.4f);
     QScroller::ScrollerGestureType gestureType = getConfiguredGestureType();
 
     if (enabled && scrollArea) {
         if (hideScrollBars) {
             scrollArea->setVerticalScrollBarPolicy(Qt::ScrollBarPolicy::ScrollBarAlwaysOff);
             scrollArea->setHorizontalScrollBarPolicy(Qt::ScrollBarPolicy::ScrollBarAlwaysOff);
         }
 
         QAbstractItemView *itemView = qobject_cast<QAbstractItemView *>(scrollArea);
         if (itemView) {
             itemView->setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
         }
 
         QScroller *scroller = QScroller::scroller(scrollArea);
         scroller->grabGesture(scrollArea, gestureType);
 
         QScrollerProperties properties;
 
         // DragStartDistance seems to be based on meter per second; though it's
         // not explicitly documented, other QScroller values are in that metric.
         // To start kinetic scrolling, with minimal sensitity, we expect a drag
         // of 10 mm, with minimum sensitity any > 0 mm.
         const float mm = 0.001f;
         const float resistance = 1.0f - (sensitivity / 100.0f);
         const float mousePressEventDelay = config.readEntry("KineticScrollingMousePressDelay", 1.0f - 0.75f * resistance);
 
         properties.setScrollMetric(QScrollerProperties::DragStartDistance, resistance * resistanceCoefficient * mm);
         properties.setScrollMetric(QScrollerProperties::DragVelocitySmoothingFactor, dragVelocitySmoothFactor);
         properties.setScrollMetric(QScrollerProperties::MinimumVelocity, minimumVelocity);
         properties.setScrollMetric(QScrollerProperties::AxisLockThreshold, axisLockThresh);
         properties.setScrollMetric(QScrollerProperties::MaximumClickThroughVelocity, maximumClickThroughVelocity);
         properties.setScrollMetric(QScrollerProperties::MousePressEventDelay, mousePressEventDelay);
         properties.setScrollMetric(QScrollerProperties::AcceleratingFlickSpeedupFactor, flickAccelerationFactor);
 
         properties.setScrollMetric(QScrollerProperties::VerticalOvershootPolicy, QScrollerProperties::OvershootAlwaysOn);
         properties.setScrollMetric(QScrollerProperties::OvershootDragResistanceFactor, overshootDragResistanceFactor);
         properties.setScrollMetric(QScrollerProperties::OvershootDragDistanceFactor, overshootDragDistanceFactor);
         properties.setScrollMetric(QScrollerProperties::OvershootScrollDistanceFactor, overshootScrollDistanceFactor);
         properties.setScrollMetric(QScrollerProperties::OvershootScrollTime, overshootScrollTime);
 
         scroller->setScrollerProperties(properties);
 
         return scroller;
     }
 
     return nullptr;
 }
 
 QScroller::ScrollerGestureType KoKineticScroller::getConfiguredGestureType()
 {
     KConfigGroup config = KSharedConfig::openConfig()->group("KoKineticScroller");
     int gesture = config.readEntry("KineticScrollingGesture", 0);
 
     switch (gesture) {
     case 0: {
         return QScroller::TouchGesture;
     }
     case 1: {
         return QScroller::LeftMouseButtonGesture;
     }
     case 2: {
         return QScroller::MiddleMouseButtonGesture;
     }
     case 3: {
         return QScroller::RightMouseButtonGesture;
     }
     default:
         return QScroller::MiddleMouseButtonGesture;
     }
 }
 
 void KoKineticScroller::updateCursor(QWidget *source, QScroller::State state)
 {
     if( state == QScroller::State::Pressed ) {
         source->setCursor(Qt::OpenHandCursor);
     } else if (state == QScroller::State::Dragging) {
         source->setCursor(Qt::ClosedHandCursor);
     } else {
         source->setCursor(Qt::ArrowCursor);
     }
 }