##// END OF EJS Templates
Added possibility to set labels position for QCategoryAxis...
Added possibility to set labels position for QCategoryAxis The position of the labels in QCategyAxis can now be set to center of the category or to the high end of the category. The first and the last labels may overlap with other axes labels when positioned on value. Change-Id: Ide0f12b723ffabf6682001e03ea5080f9642da22 Task-number: QTRD-1715 Reviewed-by: Miikka Heikkinen <miikka.heikkinen@theqtcompany.com>

File last commit:

r2776:bc1f6aa59d42
r2780:740f4f94adf8
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linechartitem.cpp
427 lines | 18.7 KiB | text/x-c | CppLexer
/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd
** All rights reserved.
** For any questions to The Qt Company, please use contact form at http://qt.io
**
** This file is part of the Qt Charts module.
**
** Licensees holding valid commercial license for Qt may use this file in
** accordance with the Qt License Agreement provided with the Software
** or, alternatively, in accordance with the terms contained in a written
** agreement between you and The Qt Company.
**
** If you have questions regarding the use of this file, please use
** contact form at http://qt.io
**
****************************************************************************/
#include <private/linechartitem_p.h>
#include <QtCharts/QLineSeries>
#include <private/qlineseries_p.h>
#include <private/chartpresenter_p.h>
#include <private/polardomain_p.h>
#include <private/chartthememanager_p.h>
#include <private/charttheme_p.h>
#include <QtGui/QPainter>
#include <QtWidgets/QGraphicsSceneMouseEvent>
QT_CHARTS_BEGIN_NAMESPACE
const qreal mouseEventMinWidth(12);
LineChartItem::LineChartItem(QLineSeries *series, QGraphicsItem *item)
: XYChart(series,item),
m_series(series),
m_pointsVisible(false),
m_chartType(QChart::ChartTypeUndefined),
m_pointLabelsVisible(false),
m_pointLabelsFormat(series->pointLabelsFormat()),
m_pointLabelsFont(series->pointLabelsFont()),
m_pointLabelsColor(series->pointLabelsColor()),
m_mousePressed(false)
{
setAcceptHoverEvents(true);
setFlag(QGraphicsItem::ItemIsSelectable);
setZValue(ChartPresenter::LineChartZValue);
QObject::connect(series->d_func(), SIGNAL(updated()), this, SLOT(handleUpdated()));
QObject::connect(series, SIGNAL(visibleChanged()), this, SLOT(handleUpdated()));
QObject::connect(series, SIGNAL(opacityChanged()), this, SLOT(handleUpdated()));
QObject::connect(series, SIGNAL(pointLabelsFormatChanged(QString)),
this, SLOT(handleUpdated()));
QObject::connect(series, SIGNAL(pointLabelsVisibilityChanged(bool)),
this, SLOT(handleUpdated()));
QObject::connect(series, SIGNAL(pointLabelsFontChanged(QFont)), this, SLOT(handleUpdated()));
QObject::connect(series, SIGNAL(pointLabelsColorChanged(QColor)), this, SLOT(handleUpdated()));
handleUpdated();
}
QRectF LineChartItem::boundingRect() const
{
return m_rect;
}
QPainterPath LineChartItem::shape() const
{
return m_shapePath;
}
void LineChartItem::updateGeometry()
{
m_points = geometryPoints();
const QVector<QPointF> &points = m_points;
if (points.size() == 0) {
prepareGeometryChange();
m_fullPath = QPainterPath();
m_linePath = QPainterPath();
m_rect = QRect();
return;
}
QPainterPath linePath;
QPainterPath fullPath;
// Use worst case scenario to determine required margin.
qreal margin = m_linePen.width() * 1.42;
// Area series use component line series that aren't necessarily added to the chart themselves,
// so check if chart type is forced before trying to obtain it from the chart.
QChart::ChartType chartType = m_chartType;
if (chartType == QChart::ChartTypeUndefined)
chartType = m_series->chart()->chartType();
// For polar charts, we need special handling for angular (horizontal)
// points that are off-grid.
if (chartType == QChart::ChartTypePolar) {
QPainterPath linePathLeft;
QPainterPath linePathRight;
QPainterPath *currentSegmentPath = 0;
QPainterPath *previousSegmentPath = 0;
qreal minX = domain()->minX();
qreal maxX = domain()->maxX();
qreal minY = domain()->minY();
QPointF currentSeriesPoint = m_series->at(0);
QPointF currentGeometryPoint = points.at(0);
QPointF previousGeometryPoint = points.at(0);
int size = m_linePen.width();
bool pointOffGrid = false;
bool previousPointWasOffGrid = (currentSeriesPoint.x() < minX || currentSeriesPoint.x() > maxX);
qreal domainRadius = domain()->size().height() / 2.0;
const QPointF centerPoint(domainRadius, domainRadius);
if (!previousPointWasOffGrid) {
fullPath.moveTo(points.at(0));
if (m_pointsVisible && currentSeriesPoint.y() >= minY) {
// Do not draw ellipses for points below minimum Y.
linePath.addEllipse(points.at(0), size, size);
fullPath.addEllipse(points.at(0), size, size);
linePath.moveTo(points.at(0));
fullPath.moveTo(points.at(0));
}
}
qreal leftMarginLine = centerPoint.x() - margin;
qreal rightMarginLine = centerPoint.x() + margin;
qreal horizontal = centerPoint.y();
// See ScatterChartItem::updateGeometry() for explanation why seriesLastIndex is needed
const int seriesLastIndex = m_series->count() - 1;
for (int i = 1; i < points.size(); i++) {
// Interpolating line fragments would be ugly when thick pen is used,
// so we work around it by utilizing three separate
// paths for line segments and clip those with custom regions at paint time.
// "Right" path contains segments that cross the axis line with visible point on the
// right side of the axis line, as well as segments that have one point within the margin
// on the right side of the axis line and another point on the right side of the chart.
// "Left" path contains points with similarly on the left side.
// "Full" path contains rest of the points.
// This doesn't yield perfect results always. E.g. when segment covers more than 90
// degrees and both of the points are within the margin, one in the top half and one in the
// bottom half of the chart, the bottom one gets clipped incorrectly.
// However, this should be rare occurrence in any sensible chart.
currentSeriesPoint = m_series->at(qMin(seriesLastIndex, i));
currentGeometryPoint = points.at(i);
pointOffGrid = (currentSeriesPoint.x() < minX || currentSeriesPoint.x() > maxX);
// Draw something unless both off-grid
if (!pointOffGrid || !previousPointWasOffGrid) {
QPointF intersectionPoint;
qreal y;
if (pointOffGrid != previousPointWasOffGrid) {
if (currentGeometryPoint.x() == previousGeometryPoint.x()) {
y = currentGeometryPoint.y() + (currentGeometryPoint.y() - previousGeometryPoint.y()) / 2.0;
} else {
qreal ratio = (centerPoint.x() - currentGeometryPoint.x()) / (currentGeometryPoint.x() - previousGeometryPoint.x());
y = currentGeometryPoint.y() + (currentGeometryPoint.y() - previousGeometryPoint.y()) * ratio;
}
intersectionPoint = QPointF(centerPoint.x(), y);
}
bool dummyOk; // We know points are ok, but this is needed
qreal currentAngle = 0;
qreal previousAngle = 0;
if (const PolarDomain *pd = qobject_cast<const PolarDomain *>(domain())) {
currentAngle = pd->toAngularCoordinate(currentSeriesPoint.x(), dummyOk);
previousAngle = pd->toAngularCoordinate(m_series->at(i - 1).x(), dummyOk);
} else {
qWarning() << Q_FUNC_INFO << "Unexpected domain: " << domain();
}
if ((qAbs(currentAngle - previousAngle) > 180.0)) {
// If the angle between two points is over 180 degrees (half X range),
// any direct segment between them becomes meaningless.
// In this case two line segments are drawn instead, from previous
// point to the center and from center to current point.
if ((previousAngle < 0.0 || (previousAngle <= 180.0 && previousGeometryPoint.x() < rightMarginLine))
&& previousGeometryPoint.y() < horizontal) {
currentSegmentPath = &linePathRight;
} else if ((previousAngle > 360.0 || (previousAngle > 180.0 && previousGeometryPoint.x() > leftMarginLine))
&& previousGeometryPoint.y() < horizontal) {
currentSegmentPath = &linePathLeft;
} else if (previousAngle > 0.0 && previousAngle < 360.0) {
currentSegmentPath = &linePath;
} else {
currentSegmentPath = 0;
}
if (currentSegmentPath) {
if (previousSegmentPath != currentSegmentPath)
currentSegmentPath->moveTo(previousGeometryPoint);
if (previousPointWasOffGrid)
fullPath.moveTo(intersectionPoint);
currentSegmentPath->lineTo(centerPoint);
fullPath.lineTo(centerPoint);
}
previousSegmentPath = currentSegmentPath;
if ((currentAngle < 0.0 || (currentAngle <= 180.0 && currentGeometryPoint.x() < rightMarginLine))
&& currentGeometryPoint.y() < horizontal) {
currentSegmentPath = &linePathRight;
} else if ((currentAngle > 360.0 || (currentAngle > 180.0 &&currentGeometryPoint.x() > leftMarginLine))
&& currentGeometryPoint.y() < horizontal) {
currentSegmentPath = &linePathLeft;
} else if (currentAngle > 0.0 && currentAngle < 360.0) {
currentSegmentPath = &linePath;
} else {
currentSegmentPath = 0;
}
if (currentSegmentPath) {
if (previousSegmentPath != currentSegmentPath)
currentSegmentPath->moveTo(centerPoint);
if (!previousSegmentPath)
fullPath.moveTo(centerPoint);
currentSegmentPath->lineTo(currentGeometryPoint);
if (pointOffGrid)
fullPath.lineTo(intersectionPoint);
else
fullPath.lineTo(currentGeometryPoint);
}
} else {
if (previousAngle < 0.0 || currentAngle < 0.0
|| ((previousAngle <= 180.0 && currentAngle <= 180.0)
&& ((previousGeometryPoint.x() < rightMarginLine && previousGeometryPoint.y() < horizontal)
|| (currentGeometryPoint.x() < rightMarginLine && currentGeometryPoint.y() < horizontal)))) {
currentSegmentPath = &linePathRight;
} else if (previousAngle > 360.0 || currentAngle > 360.0
|| ((previousAngle > 180.0 && currentAngle > 180.0)
&& ((previousGeometryPoint.x() > leftMarginLine && previousGeometryPoint.y() < horizontal)
|| (currentGeometryPoint.x() > leftMarginLine && currentGeometryPoint.y() < horizontal)))) {
currentSegmentPath = &linePathLeft;
} else {
currentSegmentPath = &linePath;
}
if (currentSegmentPath != previousSegmentPath)
currentSegmentPath->moveTo(previousGeometryPoint);
if (previousPointWasOffGrid)
fullPath.moveTo(intersectionPoint);
if (pointOffGrid)
fullPath.lineTo(intersectionPoint);
else
fullPath.lineTo(currentGeometryPoint);
currentSegmentPath->lineTo(currentGeometryPoint);
}
} else {
currentSegmentPath = 0;
}
previousPointWasOffGrid = pointOffGrid;
if (m_pointsVisible && !pointOffGrid && currentSeriesPoint.y() >= minY) {
linePath.addEllipse(points.at(i), size, size);
fullPath.addEllipse(points.at(i), size, size);
linePath.moveTo(points.at(i));
fullPath.moveTo(points.at(i));
}
previousSegmentPath = currentSegmentPath;
previousGeometryPoint = currentGeometryPoint;
}
m_linePathPolarRight = linePathRight;
m_linePathPolarLeft = linePathLeft;
// Note: This construction of m_fullpath is not perfect. The partial segments that are
// outside left/right clip regions at axis boundary still generate hover/click events,
// because shape doesn't get clipped. It doesn't seem possible to do sensibly.
} else { // not polar
linePath.moveTo(points.at(0));
if (m_pointsVisible) {
int size = m_linePen.width();
linePath.addEllipse(points.at(0), size, size);
linePath.moveTo(points.at(0));
for (int i = 1; i < points.size(); i++) {
linePath.lineTo(points.at(i));
linePath.addEllipse(points.at(i), size, size);
linePath.moveTo(points.at(i));
}
} else {
for (int i = 1; i < points.size(); i++)
linePath.lineTo(points.at(i));
}
fullPath = linePath;
}
QPainterPathStroker stroker;
// QPainter::drawLine does not respect join styles, for example BevelJoin becomes MiterJoin.
// This is why we are prepared for the "worst case" scenario, i.e. use always MiterJoin and
// multiply line width with square root of two when defining shape and bounding rectangle.
stroker.setWidth(margin);
stroker.setJoinStyle(Qt::MiterJoin);
stroker.setCapStyle(Qt::SquareCap);
stroker.setMiterLimit(m_linePen.miterLimit());
QPainterPath checkShapePath = stroker.createStroke(fullPath);
// Only zoom in if the bounding rects of the paths fit inside int limits. QWidget::update() uses
// a region that has to be compatible with QRect.
if (checkShapePath.boundingRect().height() <= INT_MAX
&& checkShapePath.boundingRect().width() <= INT_MAX
&& linePath.boundingRect().height() <= INT_MAX
&& linePath.boundingRect().width() <= INT_MAX
&& fullPath.boundingRect().height() <= INT_MAX
&& fullPath.boundingRect().width() <= INT_MAX) {
prepareGeometryChange();
m_linePath = linePath;
m_fullPath = fullPath;
m_shapePath = checkShapePath;
m_rect = m_shapePath.boundingRect();
} else {
update();
}
}
void LineChartItem::handleUpdated()
{
// If points visibility has changed, a geometry update is needed.
// Also, if pen changes when points are visible, geometry update is needed.
bool doGeometryUpdate =
(m_pointsVisible != m_series->pointsVisible())
|| (m_series->pointsVisible() && (m_linePen != m_series->pen()));
setVisible(m_series->isVisible());
setOpacity(m_series->opacity());
m_pointsVisible = m_series->pointsVisible();
m_linePen = m_series->pen();
m_pointLabelsFormat = m_series->pointLabelsFormat();
m_pointLabelsVisible = m_series->pointLabelsVisible();
m_pointLabelsFont = m_series->pointLabelsFont();
m_pointLabelsColor = m_series->pointLabelsColor();
if (doGeometryUpdate)
updateGeometry();
update();
}
void LineChartItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
{
Q_UNUSED(widget)
Q_UNUSED(option)
QRectF clipRect = QRectF(QPointF(0, 0), domain()->size());
painter->save();
painter->setPen(m_linePen);
bool alwaysUsePath = false;
if (m_series->chart()->chartType() == QChart::ChartTypePolar) {
qreal halfWidth = domain()->size().width() / 2.0;
QRectF clipRectLeft = QRectF(0, 0, halfWidth, domain()->size().height());
QRectF clipRectRight = QRectF(halfWidth, 0, halfWidth, domain()->size().height());
QRegion fullPolarClipRegion(clipRect.toRect(), QRegion::Ellipse);
QRegion clipRegionLeft(fullPolarClipRegion.intersected(clipRectLeft.toRect()));
QRegion clipRegionRight(fullPolarClipRegion.intersected(clipRectRight.toRect()));
painter->setClipRegion(clipRegionLeft);
painter->drawPath(m_linePathPolarLeft);
painter->setClipRegion(clipRegionRight);
painter->drawPath(m_linePathPolarRight);
painter->setClipRegion(fullPolarClipRegion);
alwaysUsePath = true; // required for proper clipping
} else {
painter->setClipRect(clipRect);
}
if (m_pointsVisible) {
painter->setBrush(m_linePen.color());
painter->drawPath(m_linePath);
} else {
painter->setBrush(QBrush(Qt::NoBrush));
if (m_linePen.style() != Qt::SolidLine || alwaysUsePath) {
// If pen style is not solid line, always fall back to path painting
// to ensure proper continuity of the pattern
painter->drawPath(m_linePath);
} else {
for (int i(1); i < m_points.size(); i++)
painter->drawLine(m_points.at(i - 1), m_points.at(i));
}
}
if (m_pointLabelsVisible)
m_series->d_func()->drawSeriesPointLabels(painter, m_points, m_linePen.width() / 2);
painter->restore();
}
void LineChartItem::mousePressEvent(QGraphicsSceneMouseEvent *event)
{
emit XYChart::pressed(domain()->calculateDomainPoint(event->pos()));
m_lastMousePos = event->pos();
m_mousePressed = true;
QGraphicsItem::mousePressEvent(event);
}
void LineChartItem::hoverEnterEvent(QGraphicsSceneHoverEvent *event)
{
emit XYChart::hovered(domain()->calculateDomainPoint(event->pos()), true);
// event->accept();
QGraphicsItem::hoverEnterEvent(event);
}
void LineChartItem::hoverLeaveEvent(QGraphicsSceneHoverEvent *event)
{
emit XYChart::hovered(domain()->calculateDomainPoint(event->pos()), false);
// event->accept();
QGraphicsItem::hoverEnterEvent(event);
}
void LineChartItem::mouseReleaseEvent(QGraphicsSceneMouseEvent *event)
{
emit XYChart::released(domain()->calculateDomainPoint(m_lastMousePos));
if (m_mousePressed)
emit XYChart::clicked(domain()->calculateDomainPoint(m_lastMousePos));
m_mousePressed = false;
QGraphicsItem::mouseReleaseEvent(event);
}
void LineChartItem::mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event)
{
emit XYChart::doubleClicked(domain()->calculateDomainPoint(m_lastMousePos));
QGraphicsItem::mouseDoubleClickEvent(event);
}
#include "moc_linechartitem_p.cpp"
QT_CHARTS_END_NAMESPACE