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Fix shades for log and category axes....
Fix shades for log and category axes. Partial spans at the chart edges are now shaded properly. Task-number: QTRD-1940 Change-Id: Ibe03a2b9638ccb16d9c8c9bc7f2a0f924a7115d4 Reviewed-by: Titta Heikkala <titta.heikkala@theqtcompany.com>

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r2714:929d943d1aab
r2721:cc2d0eaf2462
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polarchartaxisangular.cpp
433 lines | 17.1 KiB | text/x-c | CppLexer
/ src / charts / axis / polarchartaxisangular.cpp
/****************************************************************************
**
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** This file is part of the Qt Enterprise Charts Add-on.
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#include <private/polarchartaxisangular_p.h>
#include <private/chartpresenter_p.h>
#include <private/abstractchartlayout_p.h>
#include <QtCharts/QAbstractAxis>
#include <private/qabstractaxis_p.h>
#include <QtCore/QDebug>
#include <QtCore/QtMath>
#include <QtGui/QTextDocument>
QT_CHARTS_BEGIN_NAMESPACE
PolarChartAxisAngular::PolarChartAxisAngular(QAbstractAxis *axis, QGraphicsItem *item, bool intervalAxis)
: PolarChartAxis(axis, item, intervalAxis)
{
}
PolarChartAxisAngular::~PolarChartAxisAngular()
{
}
void PolarChartAxisAngular::updateGeometry()
{
QGraphicsLayoutItem::updateGeometry();
const QVector<qreal> &layout = this->layout();
if (layout.isEmpty())
return;
createAxisLabels(layout);
QStringList labelList = labels();
QPointF center = axisGeometry().center();
QList<QGraphicsItem *> arrowItemList = arrowItems();
QList<QGraphicsItem *> gridItemList = gridItems();
QList<QGraphicsItem *> labelItemList = labelItems();
QList<QGraphicsItem *> shadeItemList = shadeItems();
QGraphicsTextItem *title = titleItem();
QGraphicsEllipseItem *axisLine = static_cast<QGraphicsEllipseItem *>(arrowItemList.at(0));
axisLine->setRect(axisGeometry());
qreal radius = axisGeometry().height() / 2.0;
QRectF previousLabelRect;
QRectF firstLabelRect;
qreal labelHeight = 0;
bool firstShade = true;
bool nextTickVisible = false;
if (layout.size())
nextTickVisible = !(layout.at(0) < 0.0 || layout.at(0) > 360.0);
for (int i = 0; i < layout.size(); ++i) {
qreal angularCoordinate = layout.at(i);
QGraphicsLineItem *gridLineItem = static_cast<QGraphicsLineItem *>(gridItemList.at(i));
QGraphicsLineItem *tickItem = static_cast<QGraphicsLineItem *>(arrowItemList.at(i + 1));
QGraphicsTextItem *labelItem = static_cast<QGraphicsTextItem *>(labelItemList.at(i));
QGraphicsPathItem *shadeItem = 0;
if (i == 0)
shadeItem = static_cast<QGraphicsPathItem *>(shadeItemList.at(0));
else if (i % 2)
shadeItem = static_cast<QGraphicsPathItem *>(shadeItemList.at((i / 2) + 1));
// Ignore ticks outside valid range
bool currentTickVisible = nextTickVisible;
if ((i == layout.size() - 1)
|| layout.at(i + 1) < 0.0
|| layout.at(i + 1) > 360.0) {
nextTickVisible = false;
} else {
nextTickVisible = true;
}
qreal labelCoordinate = angularCoordinate;
qreal labelVisible = currentTickVisible;
if (intervalAxis()) {
qreal farEdge;
if (i == (layout.size() - 1))
farEdge = 360.0;
else
farEdge = qMin(qreal(360.0), layout.at(i + 1));
// Adjust the labelCoordinate to show it if next tick is visible
if (nextTickVisible)
labelCoordinate = qMax(qreal(0.0), labelCoordinate);
labelCoordinate = (labelCoordinate + farEdge) / 2.0;
// Don't display label once the category gets too small near the axis
if (labelCoordinate < 5.0 || labelCoordinate > 355.0)
labelVisible = false;
else
labelVisible = true;
}
// Need this also in label calculations, so determine it first
QLineF tickLine(QLineF::fromPolar(radius - tickWidth(), 90.0 - angularCoordinate).p2(),
QLineF::fromPolar(radius + tickWidth(), 90.0 - angularCoordinate).p2());
tickLine.translate(center);
// Angular axis label
if (axis()->labelsVisible() && labelVisible) {
QRectF boundingRect = ChartPresenter::textBoundingRect(axis()->labelsFont(),
labelList.at(i),
axis()->labelsAngle());
labelItem->setTextWidth(boundingRect.width());
labelItem->setHtml(labelList.at(i));
const QRectF &rect = labelItem->boundingRect();
QPointF labelCenter = rect.center();
labelItem->setTransformOriginPoint(labelCenter.x(), labelCenter.y());
boundingRect.moveCenter(labelCenter);
QPointF positionDiff(rect.topLeft() - boundingRect.topLeft());
QPointF labelPoint;
if (intervalAxis()) {
QLineF labelLine = QLineF::fromPolar(radius + tickWidth(), 90.0 - labelCoordinate);
labelLine.translate(center);
labelPoint = labelLine.p2();
} else {
labelPoint = tickLine.p2();
}
QRectF labelRect = moveLabelToPosition(labelCoordinate, labelPoint, boundingRect);
labelItem->setPos(labelRect.topLeft() + positionDiff);
// Store height for title calculations
qreal labelClearance = axisGeometry().top() - labelRect.top();
labelHeight = qMax(labelHeight, labelClearance);
// Label overlap detection
if (i && (previousLabelRect.intersects(labelRect) || firstLabelRect.intersects(labelRect))) {
labelVisible = false;
} else {
// Store labelRect for future comparison. Some area is deducted to make things look
// little nicer, as usually intersection happens at label corner with angular labels.
labelRect.adjust(-2.0, -4.0, -2.0, -4.0);
if (firstLabelRect.isEmpty())
firstLabelRect = labelRect;
previousLabelRect = labelRect;
labelVisible = true;
}
}
labelItem->setVisible(labelVisible);
if (!currentTickVisible) {
gridLineItem->setVisible(false);
tickItem->setVisible(false);
if (shadeItem)
shadeItem->setVisible(false);
continue;
}
// Angular grid line
QLineF gridLine = QLineF::fromPolar(radius, 90.0 - angularCoordinate);
gridLine.translate(center);
gridLineItem->setLine(gridLine);
gridLineItem->setVisible(true);
// Tick
tickItem->setLine(tickLine);
tickItem->setVisible(true);
// Shades
if (i % 2 || (i == 0 && !nextTickVisible)) {
QPainterPath path;
path.moveTo(center);
if (i == 0) {
// If first tick is also the last, we need to custom fill the first partial arc
// or it won't get filled.
path.arcTo(axisGeometry(), 90.0 - layout.at(0), layout.at(0));
path.closeSubpath();
} else {
qreal nextCoordinate;
if (!nextTickVisible) // Last visible tick
nextCoordinate = 360.0;
else
nextCoordinate = layout.at(i + 1);
qreal arcSpan = angularCoordinate - nextCoordinate;
path.arcTo(axisGeometry(), 90.0 - angularCoordinate, arcSpan);
path.closeSubpath();
// Add additional arc for first shade item if there is a partial arc to be filled
if (firstShade) {
QGraphicsPathItem *specialShadeItem = static_cast<QGraphicsPathItem *>(shadeItemList.at(0));
if (layout.at(i - 1) > 0.0) {
QPainterPath specialPath;
specialPath.moveTo(center);
specialPath.arcTo(axisGeometry(), 90.0 - layout.at(i - 1), layout.at(i - 1));
specialPath.closeSubpath();
specialShadeItem->setPath(specialPath);
specialShadeItem->setVisible(true);
} else {
specialShadeItem->setVisible(false);
}
}
}
shadeItem->setPath(path);
shadeItem->setVisible(true);
firstShade = false;
}
}
// Title, centered above the chart
QString titleText = axis()->titleText();
if (!titleText.isEmpty() && axis()->isTitleVisible()) {
QRectF truncatedRect;
qreal availableTitleHeight = axisGeometry().height() - labelPadding() - titlePadding() * 2.0;
qreal minimumLabelHeight = ChartPresenter::textBoundingRect(axis()->labelsFont(),
QStringLiteral("...")).height();
availableTitleHeight -= minimumLabelHeight;
title->setHtml(ChartPresenter::truncatedText(axis()->titleFont(), titleText, qreal(0.0),
axisGeometry().width(), availableTitleHeight,
truncatedRect));
title->setTextWidth(truncatedRect.width());
QRectF titleBoundingRect = title->boundingRect();
QPointF titleCenter = center - titleBoundingRect.center();
title->setPos(titleCenter.x(), axisGeometry().top() - titlePadding() * 2.0 - titleBoundingRect.height() - labelHeight);
}
}
Qt::Orientation PolarChartAxisAngular::orientation() const
{
return Qt::Horizontal;
}
void PolarChartAxisAngular::createItems(int count)
{
if (arrowItems().count() == 0) {
// angular axis line
QGraphicsEllipseItem *arrow = new QGraphicsEllipseItem(presenter()->rootItem());
arrow->setPen(axis()->linePen());
arrowGroup()->addToGroup(arrow);
}
QGraphicsTextItem *title = titleItem();
title->setFont(axis()->titleFont());
title->setDefaultTextColor(axis()->titleBrush().color());
title->setHtml(axis()->titleText());
for (int i = 0; i < count; ++i) {
QGraphicsLineItem *arrow = new QGraphicsLineItem(presenter()->rootItem());
QGraphicsLineItem *grid = new QGraphicsLineItem(presenter()->rootItem());
QGraphicsTextItem *label = new QGraphicsTextItem(presenter()->rootItem());
label->document()->setDocumentMargin(ChartPresenter::textMargin());
arrow->setPen(axis()->linePen());
grid->setPen(axis()->gridLinePen());
label->setFont(axis()->labelsFont());
label->setDefaultTextColor(axis()->labelsBrush().color());
label->setRotation(axis()->labelsAngle());
arrowGroup()->addToGroup(arrow);
gridGroup()->addToGroup(grid);
labelGroup()->addToGroup(label);
if (gridItems().size() == 1 || (((gridItems().size() + 1) % 2) && gridItems().size() > 0)) {
QGraphicsPathItem *shade = new QGraphicsPathItem(presenter()->rootItem());
shade->setPen(axis()->shadesPen());
shade->setBrush(axis()->shadesBrush());
shadeGroup()->addToGroup(shade);
}
}
}
void PolarChartAxisAngular::handleArrowPenChanged(const QPen &pen)
{
bool first = true;
foreach (QGraphicsItem *item, arrowItems()) {
if (first) {
first = false;
// First arrow item is the outer circle of axis
static_cast<QGraphicsEllipseItem *>(item)->setPen(pen);
} else {
static_cast<QGraphicsLineItem *>(item)->setPen(pen);
}
}
}
void PolarChartAxisAngular::handleGridPenChanged(const QPen &pen)
{
foreach (QGraphicsItem *item, gridItems())
static_cast<QGraphicsLineItem *>(item)->setPen(pen);
}
QSizeF PolarChartAxisAngular::sizeHint(Qt::SizeHint which, const QSizeF &constraint) const
{
Q_UNUSED(which);
Q_UNUSED(constraint);
return QSizeF(-1, -1);
}
qreal PolarChartAxisAngular::preferredAxisRadius(const QSizeF &maxSize)
{
qreal radius = maxSize.height() / 2.0;
if (maxSize.width() < maxSize.height())
radius = maxSize.width() / 2.0;
if (axis()->labelsVisible()) {
QVector<qreal> layout = calculateLayout();
if (layout.isEmpty())
return radius;
createAxisLabels(layout);
QStringList labelList = labels();
QFont font = axis()->labelsFont();
QRectF maxRect;
maxRect.setSize(maxSize);
maxRect.moveCenter(QPointF(0.0, 0.0));
// This is a horrible way to find out the maximum radius for angular axis and its labels.
// It just increments the radius down until everyhing fits the constraint size.
// Proper way would be to actually calculate it but this seems to work reasonably fast as it is.
bool nextTickVisible = false;
for (int i = 0; i < layout.size(); ) {
if ((i == layout.size() - 1)
|| layout.at(i + 1) < 0.0
|| layout.at(i + 1) > 360.0) {
nextTickVisible = false;
} else {
nextTickVisible = true;
}
qreal labelCoordinate = layout.at(i);
qreal labelVisible;
if (intervalAxis()) {
qreal farEdge;
if (i == (layout.size() - 1))
farEdge = 360.0;
else
farEdge = qMin(qreal(360.0), layout.at(i + 1));
// Adjust the labelCoordinate to show it if next tick is visible
if (nextTickVisible)
labelCoordinate = qMax(qreal(0.0), labelCoordinate);
labelCoordinate = (labelCoordinate + farEdge) / 2.0;
}
if (labelCoordinate < 0.0 || labelCoordinate > 360.0)
labelVisible = false;
else
labelVisible = true;
if (!labelVisible) {
i++;
continue;
}
QRectF boundingRect = ChartPresenter::textBoundingRect(axis()->labelsFont(), labelList.at(i), axis()->labelsAngle());
QPointF labelPoint = QLineF::fromPolar(radius + tickWidth(), 90.0 - labelCoordinate).p2();
boundingRect = moveLabelToPosition(labelCoordinate, labelPoint, boundingRect);
QRectF intersectRect = maxRect.intersected(boundingRect);
if (boundingRect.isEmpty() || intersectRect == boundingRect) {
i++;
} else {
qreal reduction(0.0);
// If there is no intersection, reduce by smallest dimension of label rect to be on the safe side
if (intersectRect.isEmpty()) {
reduction = qMin(boundingRect.height(), boundingRect.width());
} else {
// Approximate needed radius reduction is the amount label rect exceeds max rect in either dimension.
// Could be further optimized by figuring out the proper math how to calculate exact needed reduction.
reduction = qMax(boundingRect.height() - intersectRect.height(),
boundingRect.width() - intersectRect.width());
}
// Typically the approximated reduction is little low, so add one
radius -= (reduction + 1.0);
if (radius < 1.0) // safeguard
return 1.0;
}
}
}
if (!axis()->titleText().isEmpty() && axis()->isTitleVisible()) {
QRectF titleRect = ChartPresenter::textBoundingRect(axis()->titleFont(), axis()->titleText());
radius -= titlePadding() + (titleRect.height() / 2.0);
if (radius < 1.0) // safeguard
return 1.0;
}
return radius;
}
QRectF PolarChartAxisAngular::moveLabelToPosition(qreal angularCoordinate, QPointF labelPoint, QRectF labelRect) const
{
if (angularCoordinate == 0.0)
labelRect.moveCenter(labelPoint + QPointF(0, -labelRect.height() / 2.0));
else if (angularCoordinate < 90.0)
labelRect.moveBottomLeft(labelPoint);
else if (angularCoordinate == 90.0)
labelRect.moveCenter(labelPoint + QPointF(labelRect.width() / 2.0 + 2.0, 0)); // +2 so that it does not hit the radial axis
else if (angularCoordinate < 180.0)
labelRect.moveTopLeft(labelPoint);
else if (angularCoordinate == 180.0)
labelRect.moveCenter(labelPoint + QPointF(0, labelRect.height() / 2.0));
else if (angularCoordinate < 270.0)
labelRect.moveTopRight(labelPoint);
else if (angularCoordinate == 270.0)
labelRect.moveCenter(labelPoint + QPointF(-labelRect.width() / 2.0 - 2.0, 0)); // -2 so that it does not hit the radial axis
else if (angularCoordinate < 360.0)
labelRect.moveBottomRight(labelPoint);
else
labelRect.moveCenter(labelPoint + QPointF(0, -labelRect.height() / 2.0));
return labelRect;
}
#include "moc_polarchartaxisangular_p.cpp"
QT_CHARTS_END_NAMESPACE