kis_draggable_tool_button.cpp

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/*
 *  SPDX-FileCopyrightText: 2015 Dmitry Kazakov <dimula73@gmail.com>
 *
 *  SPDX-License-Identifier: GPL-2.0-or-later
 */
 
#include "kis_draggable_tool_button.h"
 
#include <QMouseEvent>
 
#include "kis_debug.h"
 
 
KisDraggableToolButton::KisDraggableToolButton(QWidget *parent)
    : QToolButton(parent),
      m_orientation(Qt::Horizontal)
{
}
 
KisDraggableToolButton::~KisDraggableToolButton()
{
}
 
void KisDraggableToolButton::beginDrag(const QPoint &pos)
{
    m_startPoint = pos;
    m_lastPosition = m_startPoint;
}
 
int KisDraggableToolButton::continueDrag(const QPoint &pos)
{
    QPoint diff = pos - m_startPoint;
 
    int value = 0;
 
    qreal tanx = diff.x() != 0 ? qAbs(qreal(diff.y()) / diff.x()) : 100.0;
 
    if (tanx > 10 && m_orientation == Qt::Horizontal) {
        m_orientation = Qt::Vertical;
    } else if (tanx < 0.1 && m_orientation == Qt::Vertical) {
        m_orientation = Qt::Horizontal;
    }
 
    // people like it more when the they can zoom by dragging in both directions
    Q_UNUSED(m_orientation);
 
    value = diff.x() - diff.y();
 
    return value;
}
 
int KisDraggableToolButton::movementDelta(const QPoint &pos)
{
    QPoint diff = pos - m_lastPosition;
    m_lastPosition = pos;
    return diff.x() - diff.y();
 
}
 
void KisDraggableToolButton::mousePressEvent(QMouseEvent *e)
{
    beginDrag(e->pos());
    QToolButton::mousePressEvent(e);
}
 
void KisDraggableToolButton::mouseMoveEvent(QMouseEvent *e)
{
    int distance = continueDrag(e->pos());
    Q_EMIT offsetChanged(distance);
    int delta = movementDelta(e->pos());
    Q_EMIT valueChanged(delta);
 
    QToolButton::mouseMoveEvent(e);
}