##// END OF EJS Templates
Introducing vertical and horizontal factors to control the position of the pie.
Introducing vertical and horizontal factors to control the position of the pie.

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r454:06980850b7dd
r454:06980850b7dd
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pieslice.cpp
208 lines | 5.5 KiB | text/x-c | CppLexer
#include "pieslice_p.h"
#include "piepresenter_p.h"
#include "qpieseries.h"
#include "qpieslice.h"
#include <QPainter>
#include <QDebug>
#include <qmath.h>
#include <QGraphicsSceneEvent>
#include <QTime>
QTCOMMERCIALCHART_BEGIN_NAMESPACE
#define PI 3.14159265 // TODO: is this defined in some header?
QPointF offset(qreal angle, qreal length)
{
qreal dx = qSin(angle*(PI/180)) * length;
qreal dy = qCos(angle*(PI/180)) * length;
return QPointF(dx, -dy);
}
PieSlice::PieSlice(QGraphicsItem* parent)
:QGraphicsObject(parent),
m_pieRadius(0),
m_startAngle(0),
m_angleSpan(0),
m_isExploded(false),
m_explodeDistanceFactor(0),
m_labelVisible(false),
m_labelArmLengthFactor(0)
{
setAcceptHoverEvents(true);
setAcceptedMouseButtons(Qt::LeftButton);
}
PieSlice::~PieSlice()
{
}
QRectF PieSlice::boundingRect() const
{
return m_slicePath.boundingRect();
}
QPainterPath PieSlice::shape() const
{
// Don't include the label and label arm.
// This is used to detect a mouse clicks. We do not want clicks from label.
return m_slicePath;
}
void PieSlice::paint(QPainter* painter, const QStyleOptionGraphicsItem* /*option*/, QWidget* /*widget*/)
{
painter->setClipRect(parentItem()->boundingRect());
painter->save();
painter->setPen(m_pen);
painter->setBrush(m_brush);
painter->drawPath(m_slicePath);
painter->restore();
if (m_labelVisible) {
painter->save();
painter->setPen(m_labelArmPen);
painter->drawPath(m_labelArmPath);
painter->restore();
painter->setFont(m_labelFont);
painter->drawText(m_labelTextRect.bottomLeft(), m_labelText);
}
}
void PieSlice::hoverEnterEvent(QGraphicsSceneHoverEvent* /*event*/)
{
emit hoverEnter();
}
void PieSlice::hoverLeaveEvent(QGraphicsSceneHoverEvent* /*event*/)
{
emit hoverLeave();
}
void PieSlice::mousePressEvent(QGraphicsSceneMouseEvent* /*event*/)
{
emit clicked();
}
void PieSlice::setPieCenterAndRadius(QPointF center, qreal radius)
{
m_pieCenter = center;
m_pieRadius = radius;
}
void PieSlice::updateGeometry()
{
if (m_pieRadius <= 0)
return;
prepareGeometryChange();
// update slice path
qreal centerAngle;
QPointF armStart;
m_slicePath = slicePath(m_pieCenter, m_pieRadius, m_startAngle, m_angleSpan, m_isExploded, m_pieRadius * m_explodeDistanceFactor, &centerAngle, &armStart);
// update text rect
m_labelTextRect = labelTextRect(m_labelFont, m_labelText);
// update label arm path
QPointF labelTextStart;
m_labelArmPath = labelArmPath(armStart, centerAngle, m_pieRadius * m_labelArmLengthFactor, m_labelTextRect.width(), &labelTextStart);
// update text position
m_labelTextRect.moveBottomLeft(labelTextStart);
//qDebug() << "PieSlice::updateGeometry" << m_labelText << boundingRect() << m_startAngle << m_startAngle + m_angleSpan;
}
void PieSlice::updateData(const QPieSlice* sliceData)
{
// TODO: compare what has changes to avoid unneccesary geometry updates
m_startAngle = sliceData->startAngle();
m_angleSpan = sliceData->m_angleSpan;
m_isExploded = sliceData->isExploded();
m_explodeDistanceFactor = sliceData->explodeDistanceFactor();
m_pen = sliceData->pen();
m_brush = sliceData->brush();
m_labelVisible = sliceData->isLabelVisible();
m_labelText = sliceData->label();
m_labelFont = sliceData->labelFont();
m_labelArmLengthFactor = sliceData->labelArmLengthFactor();
m_labelArmPen = sliceData->labelPen();
updateGeometry();
update();
}
QPainterPath PieSlice::slicePath(QPointF center, qreal radius, qreal startAngle, qreal angleSpan, bool exploded, qreal explodeDistance, qreal* centerAngle, QPointF* armStart)
{
// calculate center angle
*centerAngle = startAngle + (angleSpan/2);
// calculate slice rectangle
QRectF rect(center.x()-radius, center.y()-radius, radius*2, radius*2);
// adjust rect for exploding
if (exploded) {
qreal dx = qSin(*centerAngle*(PI/180)) * explodeDistance;
qreal dy = -qCos(*centerAngle*(PI/180)) * explodeDistance;
rect.translate(dx, dy);
}
// slice path
// TODO: draw the shape so that it might have a hole in the center
QPainterPath path;
path.moveTo(rect.center());
path.arcTo(rect, -startAngle + 90, -angleSpan);
path.closeSubpath();
// calculate label arm start point
*armStart = center;
if (exploded)
*armStart += offset(*centerAngle, explodeDistance + radius + PIESLICE_LABEL_GAP);
else
*armStart += offset(*centerAngle, radius + PIESLICE_LABEL_GAP);
return path;
}
QPainterPath PieSlice::labelArmPath(QPointF start, qreal angle, qreal length, qreal textWidth, QPointF* textStart)
{
qreal dx = qSin(angle*(PI/180)) * length;
qreal dy = -qCos(angle*(PI/180)) * length;
QPointF parm1 = start + QPointF(dx, dy);
QPointF parm2 = parm1;
if (angle < 180) { // arm swings the other way on the left side
parm2 += QPointF(textWidth, 0);
*textStart = parm1;
}
else {
parm2 += QPointF(-textWidth,0);
*textStart = parm2;
}
// elevate the text position a bit so that it does not hit the line
*textStart += QPointF(0, -5);
QPainterPath path;
path.moveTo(start);
path.lineTo(parm1);
path.lineTo(parm2);
return path;
}
QRectF PieSlice::labelTextRect(QFont font, QString text)
{
QFontMetricsF fm(font);
return fm.boundingRect(text);
}
#include "moc_pieslice_p.cpp"
QTCOMMERCIALCHART_END_NAMESPACE