Chris@57: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
cannam@45: 
cannam@45: /*
Chris@57:     EasyMercurial
cannam@45: 
Chris@57:     Based on HgExplorer by Jari Korhonen
Chris@57:     Copyright (c) 2010 Jari Korhonen
Chris@644:     Copyright (c) 2013 Chris Cannam
Chris@644:     Copyright (c) 2013 Queen Mary, University of London
Chris@57:     
cannam@45:     This program is free software; you can redistribute it and/or
cannam@45:     modify it under the terms of the GNU General Public License as
cannam@45:     published by the Free Software Foundation; either version 2 of the
cannam@45:     License, or (at your option) any later version.  See the file
cannam@45:     COPYING included with this distribution for more information.
cannam@45: */
cannam@45: 
cannam@45: #include "panned.h"
Chris@131: #include "debug.h"
cannam@45: 
cannam@45: #include <QScrollBar>
Chris@53: #include <QWheelEvent>
Chris@168: #include <QTimer>
Chris@168: 
Chris@168: #include <cmath>
cannam@45: 
cannam@45: #include <iostream>
cannam@45: 
Chris@168: Panned::Panned() :
Chris@168:     m_dragging(false)
cannam@45: {
Chris@168:     m_dragTimer = new QTimer(this);
Chris@168:     m_dragTimerMs = 50;
Chris@168:     connect(m_dragTimer, SIGNAL(timeout()), this, SLOT(dragTimerTimeout()));
Chris@56:     setRenderHints(QPainter::Antialiasing |
Chris@56:                    QPainter::TextAntialiasing);
Chris@679: 
Chris@679:     double baseEm;
Chris@679: #ifdef Q_OS_MAC
Chris@679:     baseEm = 17.0;
Chris@679: #else
Chris@679:     baseEm = 15.0;
Chris@679: #endif
Chris@679:     double em = QFontMetrics(QFont()).height();
Chris@679:     double ratio = em / baseEm;
Chris@679: 
Chris@679:     QMatrix m = matrix();
Chris@679:     m.scale(ratio, ratio);
Chris@679:     setMatrix(m);
cannam@45: }
cannam@45: 
cannam@45: void
cannam@45: Panned::resizeEvent(QResizeEvent *ev)
cannam@45: {
Chris@131:     DEBUG << "Panned::resizeEvent()" << endl;
Chris@131: 
Chris@60:     QPointF nearpt = mapToScene(0, 0);
Chris@60:     QPointF farpt = mapToScene(width(), height());
Chris@60:     QSizeF sz(farpt.x()-nearpt.x(), farpt.y()-nearpt.y());
Chris@60:     QRectF pr(nearpt, sz);
cannam@45: 
Chris@132:     QGraphicsView::resizeEvent(ev);
Chris@132: 
cannam@45:     if (pr != m_pannedRect) {
Chris@132:         DEBUG << "Panned: setting panned rect to " << pr << endl;
cannam@45:         m_pannedRect = pr;
Chris@133:         centerOn(pr.center());
Chris@133:         emit pannedRectChanged(pr);
Chris@133:     }
Chris@133: }
Chris@133: 
Chris@133: void
Chris@133: Panned::setScene(QGraphicsScene *s)
Chris@133: {
Chris@133:     if (!scene()) {
Chris@133:         QGraphicsView::setScene(s);
Chris@133:         return;
Chris@133:     }
Chris@133: 
Chris@133:     QPointF nearpt = mapToScene(0, 0);
Chris@133:     QPointF farpt = mapToScene(width(), height());
Chris@133:     QSizeF sz(farpt.x()-nearpt.x(), farpt.y()-nearpt.y());
Chris@133:     QRectF pr(nearpt, sz);
Chris@133: 
Chris@133:     QGraphicsView::setScene(s);
Chris@133: 
Chris@133:     DEBUG << "Panned::setScene: pr = " << pr << ", sceneRect = " << sceneRect() << endl;
Chris@133: 
Chris@133:     if (scene() && sceneRect().intersects(pr)) {
Chris@133:         DEBUG << "Panned::setScene: restoring old rect " << pr << endl;
Chris@133:         m_pannedRect = pr;
Chris@133:         centerOn(pr.center());
cannam@45:         emit pannedRectChanged(pr);
cannam@45:     }
cannam@45: }
cannam@45: 
cannam@45: void
cannam@45: Panned::paintEvent(QPaintEvent *e)
cannam@45: {
cannam@45:     QGraphicsView::paintEvent(e);
cannam@45: }
cannam@45: 
cannam@45: void
Chris@671: Panned::drawForeground(QPainter *, const QRectF &)
cannam@45: {
Chris@60:     QPointF nearpt = mapToScene(0, 0);
Chris@60:     QPointF farpt = mapToScene(width(), height());
Chris@60:     QSizeF sz(farpt.x()-nearpt.x(), farpt.y()-nearpt.y());
Chris@60:     QRectF pr(nearpt, sz);
cannam@45: 
cannam@45:     if (pr != m_pannedRect) {
Chris@133:         DEBUG << "Panned::drawForeground: visible rect " << pr << " differs from panned rect " << m_pannedRect << ", updating panned rect" <<endl;
cannam@45:         if (pr.x() != m_pannedRect.x()) emit pannedContentsScrolled();
cannam@45:         m_pannedRect = pr;
cannam@45:         emit pannedRectChanged(pr);
cannam@45:     }
cannam@45: }
cannam@45: 
cannam@45: void
Chris@53: Panned::zoomIn()
Chris@53: {
Chris@53:     QMatrix m = matrix();
Chris@53:     m.scale(1.0 / 1.1, 1.0 / 1.1);
Chris@53:     setMatrix(m);
Chris@53: }
Chris@53: 
Chris@53: void
Chris@53: Panned::zoomOut()
Chris@53: {
Chris@53:     QMatrix m = matrix();
Chris@53:     m.scale(1.1, 1.1);
Chris@53:     setMatrix(m);
Chris@53: }
Chris@53: 
Chris@53: void
cannam@45: Panned::slotSetPannedRect(QRectF pr)
cannam@45: {
cannam@45:     centerOn(pr.center());
cannam@45: //	setSceneRect(pr);
cannam@45: //	m_pannedRect = pr;
cannam@45: }
cannam@45: 
cannam@45: void
cannam@45: Panned::wheelEvent(QWheelEvent *ev)
cannam@45: {
Chris@53:     if (ev->modifiers() & Qt::ControlModifier) {
Chris@53:         int d = ev->delta();
Chris@53:         if (d > 0) {
Chris@53:             while (d > 0) {
Chris@53:                 zoomOut();
Chris@53:                 d -= 120;
Chris@53:             }
Chris@53:         } else {
Chris@53:             while (d < 0) {
Chris@53:                 zoomIn();
Chris@53:                 d += 120;
Chris@53:             }
Chris@53:         }
Chris@53:     } else {
Chris@53:         emit wheelEventReceived(ev);
Chris@53:         QGraphicsView::wheelEvent(ev);
Chris@53:     }
cannam@45: }
cannam@45: 
cannam@45: void
cannam@45: Panned::slotEmulateWheelEvent(QWheelEvent *ev)
cannam@45: {
cannam@45:     QGraphicsView::wheelEvent(ev);
cannam@45: }
cannam@45: 
cannam@45: void
Chris@168: Panned::mousePressEvent(QMouseEvent *ev)
Chris@168: {
Chris@168:     if (dragMode() != QGraphicsView::ScrollHandDrag ||
Chris@168:         ev->button() != Qt::LeftButton) {
Chris@168:         QGraphicsView::mousePressEvent(ev);
Chris@168:         return;
Chris@168:     }
Chris@168: 
Chris@168:     DEBUG << "Panned::mousePressEvent: have left button in drag mode" << endl;
Chris@168: 
Chris@168:     setDragMode(QGraphicsView::NoDrag);
Chris@168:     QGraphicsView::mousePressEvent(ev);
Chris@168:     setDragMode(QGraphicsView::ScrollHandDrag);
Chris@168: 
Chris@168:     if (!ev->isAccepted()) {
Chris@168:         ev->accept();
Chris@168:         m_dragging = true;
Chris@168:         m_lastDragPos = ev->pos();
Chris@403:         m_lastDragStart = ev->pos();
Chris@168:         m_lastOrigin = QPoint(horizontalScrollBar()->value(),
Chris@168:                               verticalScrollBar()->value());
Chris@168:         m_velocity = QPointF(0, 0);
Chris@168:         m_dragTimer->start(m_dragTimerMs);
Chris@403:         m_dragDirection = UnknownDrag;
Chris@403:     }
Chris@403: }
Chris@403: 
Chris@403: void
Chris@403: Panned::updateDragDirection(QPoint pos)
Chris@403: {
Chris@403:     if (m_dragDirection == FreeDrag) {
Chris@403:         return;
Chris@168:     }
Chris@168: 
Chris@403:     QPoint overall = pos - m_lastDragStart;
Chris@403: 
Chris@403:     int smallThreshold = 10;
Chris@403:     int largeThreshold = 30;
Chris@403:     int dx = qAbs(overall.x());
Chris@403:     int dy = qAbs(overall.y());
Chris@403: 
Chris@403:     switch (m_dragDirection) {
Chris@403: 
Chris@403:     case UnknownDrag:
Chris@403:         if (dx > smallThreshold) {
Chris@403:             if (dy > smallThreshold) {
Chris@403:                 m_dragDirection = FreeDrag;
Chris@403:             } else {
Chris@403:                 m_dragDirection = HorizontalDrag;
Chris@403:             }
Chris@403:         } else if (dy > smallThreshold) {
Chris@403:             m_dragDirection = VerticalDrag;
Chris@403:         }
Chris@403:         break;
Chris@403: 
Chris@403:     case HorizontalDrag:
Chris@403:         if (dy > largeThreshold) {
Chris@403:             m_dragDirection = FreeDrag;
Chris@403:         }
Chris@403:         break;
Chris@403: 
Chris@403:     case VerticalDrag:
Chris@403:         if (dx > largeThreshold) {
Chris@403:             m_dragDirection = FreeDrag;
Chris@403:         }
Chris@403:         break;
Chris@671: 
Chris@671:     case FreeDrag:
Chris@671:         // stick with it
Chris@671:         break;
Chris@403:     };
Chris@168: }
Chris@168: 
Chris@168: void
Chris@168: Panned::mouseMoveEvent(QMouseEvent *ev)
Chris@168: {
Chris@168:     if (!m_dragging) {
Chris@168:         QGraphicsView::mouseMoveEvent(ev);
Chris@168:         return;
Chris@168:     }
Chris@168:     DEBUG << "Panned::mouseMoveEvent: dragging" << endl;
Chris@168:     ev->accept();
Chris@403:     updateDragDirection(ev->pos());
Chris@168:     QScrollBar *hBar = horizontalScrollBar();
Chris@168:     QScrollBar *vBar = verticalScrollBar();
Chris@168:     QPoint delta = ev->pos() - m_lastDragPos;
Chris@403:     if (m_dragDirection != VerticalDrag) {
Chris@403:         hBar->setValue(hBar->value() +
Chris@403:                        (isRightToLeft() ? delta.x() : -delta.x()));
Chris@403:     }
Chris@403:     if (m_dragDirection != HorizontalDrag) {
Chris@403:         vBar->setValue(vBar->value() - delta.y());
Chris@403:     }
Chris@168:     m_lastDragPos = ev->pos();
Chris@168: }
Chris@168: 
Chris@168: void
Chris@168: Panned::mouseReleaseEvent(QMouseEvent *ev)
Chris@168: {
Chris@168:     if (!m_dragging) {
Chris@168:         QGraphicsView::mouseReleaseEvent(ev);
Chris@168:         return;
Chris@168:     }
Chris@168:     DEBUG << "Panned::mouseReleaseEvent: dragging" << endl;
Chris@168:     ev->accept();
Chris@168:     m_dragging = false;
Chris@168: }
Chris@168: 
Chris@168: void
Chris@168: Panned::dragTimerTimeout()
Chris@168: {
Chris@168:     QPoint origin = QPoint(horizontalScrollBar()->value(),
Chris@168:                            verticalScrollBar()->value());
Chris@168:     if (m_dragging) {
Chris@168:         m_velocity = QPointF
Chris@168:             (float(origin.x() - m_lastOrigin.x()) / m_dragTimerMs,
Chris@168:              float(origin.y() - m_lastOrigin.y()) / m_dragTimerMs);
Chris@168:         m_lastOrigin = origin;
Chris@168:         DEBUG << "Panned::dragTimerTimeout: velocity = " << m_velocity << endl;
Chris@168:     } else {
Chris@168:         if (origin == m_lastOrigin) {
Chris@168:             m_dragTimer->stop();
Chris@168:         }
Chris@168:         float x = m_velocity.x(), y = m_velocity.y();
Chris@168:         if (fabsf(x) > 1.0/m_dragTimerMs) x = x * 0.9f;
Chris@168:         else x = 0.f;
Chris@168:         if (fabsf(y) > 1.0/m_dragTimerMs) y = y * 0.9f;
Chris@168:         else y = 0.f;
Chris@168:         m_velocity = QPointF(x, y);
Chris@168:         DEBUG << "Panned::dragTimerTimeout: velocity adjusted to " << m_velocity << endl;
Chris@168:         m_lastOrigin = origin;
Chris@168:         //!!! need to store origin in floats
Chris@403:         if (m_dragDirection != VerticalDrag) {
Chris@403:             horizontalScrollBar()->setValue(m_lastOrigin.x() +
Chris@403:                                             m_velocity.x() * m_dragTimerMs);
Chris@403:         }
Chris@403:         if (m_dragDirection != HorizontalDrag) {
Chris@403:             verticalScrollBar()->setValue(m_lastOrigin.y() +
Chris@403:                                           m_velocity.y() * m_dragTimerMs);
Chris@403:         }
Chris@168:     }
Chris@168: }
Chris@168: 
Chris@168: void
cannam@45: Panned::leaveEvent(QEvent *)
cannam@45: {
cannam@45:     emit mouseLeaves();
cannam@45: }