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Diffstat (limited to 'src/charts/linechart/linechartitem.cpp')
-rw-r--r-- | src/charts/linechart/linechartitem.cpp | 405 |
1 files changed, 405 insertions, 0 deletions
diff --git a/src/charts/linechart/linechartitem.cpp b/src/charts/linechart/linechartitem.cpp new file mode 100644 index 00000000..1a87342e --- /dev/null +++ b/src/charts/linechart/linechartitem.cpp @@ -0,0 +1,405 @@ +/**************************************************************************** +** +** Copyright (C) 2014 Digia Plc +** All rights reserved. +** For any questions to Digia, please use contact form at http://qt.digia.com +** +** This file is part of the Qt Enterprise Charts Add-on. +** +** $QT_BEGIN_LICENSE$ +** Licensees holding valid Qt Enterprise licenses may use this file in +** accordance with the Qt Enterprise License Agreement provided with the +** Software or, alternatively, in accordance with the terms contained in +** a written agreement between you and Digia. +** +** If you have questions regarding the use of this file, please use +** contact form at http://qt.digia.com +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "linechartitem_p.h" +#include "qlineseries.h" +#include "qlineseries_p.h" +#include "chartpresenter_p.h" +#include "polardomain_p.h" +#include "chartthememanager_p.h" +#include "charttheme_p.h" +#include <QPainter> +#include <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()) +{ + setAcceptHoverEvents(true); + 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 = static_cast<PolarDomain *>(domain())->toAngularCoordinate(currentSeriesPoint.x(), dummyOk); + qreal previousAngle = static_cast<PolarDomain *>(domain())->toAngularCoordinate(m_series->at(i - 1).x(), dummyOk); + + 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 &¤tGeometryPoint.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::clicked(domain()->calculateDomainPoint(event->pos())); + 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); +} + +#include "moc_linechartitem_p.cpp" + +QT_CHARTS_END_NAMESPACE |