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Diffstat (limited to 'src/charts/splinechart/splinechartitem.cpp')
| -rw-r--r-- | src/charts/splinechart/splinechartitem.cpp | 485 |
1 files changed, 485 insertions, 0 deletions
diff --git a/src/charts/splinechart/splinechartitem.cpp b/src/charts/splinechart/splinechartitem.cpp new file mode 100644 index 00000000..d47cd7ce --- /dev/null +++ b/src/charts/splinechart/splinechartitem.cpp @@ -0,0 +1,485 @@ +/**************************************************************************** + ** + ** 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 "splinechartitem_p.h" +#include "qsplineseries_p.h" +#include "chartpresenter_p.h" +#include "splineanimation_p.h" +#include "polardomain_p.h" +#include <QPainter> +#include <QGraphicsSceneMouseEvent> + +QT_CHARTS_BEGIN_NAMESPACE + +SplineChartItem::SplineChartItem(QSplineSeries *series, QGraphicsItem *item) + : XYChart(series,item), + m_series(series), + m_pointsVisible(false), + m_animation(0), + m_pointLabelsVisible(false), + m_pointLabelsFormat(series->pointLabelsFormat()), + m_pointLabelsFont(series->pointLabelsFont()), + m_pointLabelsColor(series->pointLabelsColor()) +{ + setAcceptHoverEvents(true); + setZValue(ChartPresenter::SplineChartZValue); + QObject::connect(m_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 SplineChartItem::boundingRect() const +{ + return m_rect; +} + +QPainterPath SplineChartItem::shape() const +{ + return m_fullPath; +} + +void SplineChartItem::setAnimation(SplineAnimation *animation) +{ + m_animation = animation; + XYChart::setAnimation(animation); +} + +ChartAnimation *SplineChartItem::animation() const +{ + return m_animation; +} + +void SplineChartItem::setControlGeometryPoints(QVector<QPointF>& points) +{ + m_controlPoints = points; +} + +QVector<QPointF> SplineChartItem::controlGeometryPoints() const +{ + return m_controlPoints; +} + +void SplineChartItem::updateChart(QVector<QPointF> &oldPoints, QVector<QPointF> &newPoints, int index) +{ + QVector<QPointF> controlPoints; + if (newPoints.count() >= 2) + controlPoints = calculateControlPoints(newPoints); + + if (m_animation) + m_animation->setup(oldPoints, newPoints, m_controlPoints, controlPoints, index); + + m_points = newPoints; + m_controlPoints = controlPoints; + setDirty(false); + + if (m_animation) + presenter()->startAnimation(m_animation); + else + updateGeometry(); +} + +void SplineChartItem::updateGeometry() +{ + const QVector<QPointF> &points = m_points; + const QVector<QPointF> &controlPoints = m_controlPoints; + + if ((points.size() < 2) || (controlPoints.size() < 2)) { + prepareGeometryChange(); + m_path = QPainterPath(); + m_rect = QRect(); + return; + } + + Q_ASSERT(points.count() * 2 - 2 == controlPoints.count()); + + QPainterPath splinePath; + QPainterPath fullPath; + // Use worst case scenario to determine required margin. + qreal margin = m_linePen.width() * 1.42; + + if (m_series->chart()->chartType() == QChart::ChartTypePolar) { + QPainterPath splinePathLeft; + QPainterPath splinePathRight; + 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); + bool pointOffGrid = false; + bool previousPointWasOffGrid = (currentSeriesPoint.x() < minX || currentSeriesPoint.x() > maxX); + m_visiblePoints.clear(); + m_visiblePoints.reserve(points.size()); + + qreal domainRadius = domain()->size().height() / 2.0; + const QPointF centerPoint(domainRadius, domainRadius); + + if (!previousPointWasOffGrid) { + fullPath.moveTo(points.at(0)); + // Do not draw points for points below minimum Y. + if (m_pointsVisible && currentSeriesPoint.y() >= minY) + m_visiblePoints.append(currentGeometryPoint); + } + + 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 spline fragments accurately is not trivial, and would anyway be ugly + // when thick pen is used, so we work around it by utilizing three separate + // paths for spline 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) { + 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 = &splinePathRight; + } else if ((previousAngle > 360.0 || (previousAngle > 180.0 && previousGeometryPoint.x() > leftMarginLine)) + && previousGeometryPoint.y() < horizontal) { + currentSegmentPath = &splinePathLeft; + } else if (previousAngle > 0.0 && previousAngle < 360.0) { + currentSegmentPath = &splinePath; + } else { + currentSegmentPath = 0; + } + + if (currentSegmentPath) { + if (previousSegmentPath != currentSegmentPath) + currentSegmentPath->moveTo(previousGeometryPoint); + if (!previousSegmentPath) + fullPath.moveTo(previousGeometryPoint); + + currentSegmentPath->lineTo(centerPoint); + fullPath.lineTo(centerPoint); + } + + previousSegmentPath = currentSegmentPath; + + if ((currentAngle < 0.0 || (currentAngle <= 180.0 && currentGeometryPoint.x() < rightMarginLine)) + && currentGeometryPoint.y() < horizontal) { + currentSegmentPath = &splinePathRight; + } else if ((currentAngle > 360.0 || (currentAngle > 180.0 &¤tGeometryPoint.x() > leftMarginLine)) + && currentGeometryPoint.y() < horizontal) { + currentSegmentPath = &splinePathLeft; + } else if (currentAngle > 0.0 && currentAngle < 360.0) { + currentSegmentPath = &splinePath; + } else { + currentSegmentPath = 0; + } + + if (currentSegmentPath) { + if (previousSegmentPath != currentSegmentPath) + currentSegmentPath->moveTo(centerPoint); + if (!previousSegmentPath) + fullPath.moveTo(centerPoint); + + currentSegmentPath->lineTo(currentGeometryPoint); + fullPath.lineTo(currentGeometryPoint); + } + } else { + QPointF cp1 = controlPoints[2 * (i - 1)]; + QPointF cp2 = controlPoints[(2 * i) - 1]; + + 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 = &splinePathRight; + } 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 = &splinePathLeft; + } else { + currentSegmentPath = &splinePath; + } + + if (currentSegmentPath != previousSegmentPath) + currentSegmentPath->moveTo(previousGeometryPoint); + if (!previousSegmentPath) + fullPath.moveTo(previousGeometryPoint); + + fullPath.cubicTo(cp1, cp2, currentGeometryPoint); + currentSegmentPath->cubicTo(cp1, cp2, currentGeometryPoint); + } + } else { + currentSegmentPath = 0; + } + + previousPointWasOffGrid = pointOffGrid; + if (!pointOffGrid && m_pointsVisible && currentSeriesPoint.y() >= minY) + m_visiblePoints.append(currentGeometryPoint); + previousSegmentPath = currentSegmentPath; + previousGeometryPoint = currentGeometryPoint; + } + + m_pathPolarRight = splinePathRight; + m_pathPolarLeft = splinePathLeft; + // 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 + splinePath.moveTo(points.at(0)); + for (int i = 0; i < points.size() - 1; i++) { + const QPointF &point = points.at(i + 1); + splinePath.cubicTo(controlPoints[2 * i], controlPoints[2 * i + 1], point); + } + fullPath = splinePath; + } + + QPainterPathStroker stroker; + // The full path is comprised of three separate paths. + // 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()); + + // Only zoom in if the bounding rects of the path fit inside int limits. QWidget::update() uses + // a region that has to be compatible with QRect. + QPainterPath checkShapePath = stroker.createStroke(fullPath); + if (checkShapePath.boundingRect().height() <= INT_MAX + && checkShapePath.boundingRect().width() <= INT_MAX + && splinePath.boundingRect().height() <= INT_MAX + && splinePath.boundingRect().width() <= INT_MAX) { + m_path = splinePath; + + prepareGeometryChange(); + + m_fullPath = checkShapePath; + m_rect = m_fullPath.boundingRect(); + } +} + +/*! + Calculates control points which are needed by QPainterPath.cubicTo function to draw the cubic Bezier cureve between two points. + */ +QVector<QPointF> SplineChartItem::calculateControlPoints(const QVector<QPointF> &points) +{ + QVector<QPointF> controlPoints; + controlPoints.resize(points.count() * 2 - 2); + + int n = points.count() - 1; + + if (n == 1) { + //for n==1 + controlPoints[0].setX((2 * points[0].x() + points[1].x()) / 3); + controlPoints[0].setY((2 * points[0].y() + points[1].y()) / 3); + controlPoints[1].setX(2 * controlPoints[0].x() - points[0].x()); + controlPoints[1].setY(2 * controlPoints[0].y() - points[0].y()); + return controlPoints; + } + + // Calculate first Bezier control points + // Set of equations for P0 to Pn points. + // + // | 2 1 0 0 ... 0 0 0 ... 0 0 0 | | P1_1 | | P0 + 2 * P1 | + // | 1 4 1 0 ... 0 0 0 ... 0 0 0 | | P1_2 | | 4 * P1 + 2 * P2 | + // | 0 1 4 1 ... 0 0 0 ... 0 0 0 | | P1_3 | | 4 * P2 + 2 * P3 | + // | . . . . . . . . . . . . | | ... | | ... | + // | 0 0 0 0 ... 1 4 1 ... 0 0 0 | * | P1_i | = | 4 * P(i-1) + 2 * Pi | + // | . . . . . . . . . . . . | | ... | | ... | + // | 0 0 0 0 0 0 0 0 ... 1 4 1 | | P1_(n-1)| | 4 * P(n-2) + 2 * P(n-1) | + // | 0 0 0 0 0 0 0 0 ... 0 2 7 | | P1_n | | 8 * P(n-1) + Pn | + // + QVector<qreal> vector; + vector.resize(n); + + vector[0] = points[0].x() + 2 * points[1].x(); + + + for (int i = 1; i < n - 1; ++i) + vector[i] = 4 * points[i].x() + 2 * points[i + 1].x(); + + vector[n - 1] = (8 * points[n - 1].x() + points[n].x()) / 2.0; + + QVector<qreal> xControl = firstControlPoints(vector); + + vector[0] = points[0].y() + 2 * points[1].y(); + + for (int i = 1; i < n - 1; ++i) + vector[i] = 4 * points[i].y() + 2 * points[i + 1].y(); + + vector[n - 1] = (8 * points[n - 1].y() + points[n].y()) / 2.0; + + QVector<qreal> yControl = firstControlPoints(vector); + + for (int i = 0, j = 0; i < n; ++i, ++j) { + + controlPoints[j].setX(xControl[i]); + controlPoints[j].setY(yControl[i]); + + j++; + + if (i < n - 1) { + controlPoints[j].setX(2 * points[i + 1].x() - xControl[i + 1]); + controlPoints[j].setY(2 * points[i + 1].y() - yControl[i + 1]); + } else { + controlPoints[j].setX((points[n].x() + xControl[n - 1]) / 2); + controlPoints[j].setY((points[n].y() + yControl[n - 1]) / 2); + } + } + return controlPoints; +} + +QVector<qreal> SplineChartItem::firstControlPoints(const QVector<qreal>& vector) +{ + QVector<qreal> result; + + int count = vector.count(); + result.resize(count); + result[0] = vector[0] / 2.0; + + QVector<qreal> temp; + temp.resize(count); + temp[0] = 0; + + qreal b = 2.0; + + for (int i = 1; i < count; i++) { + temp[i] = 1 / b; + b = (i < count - 1 ? 4.0 : 3.5) - temp[i]; + result[i] = (vector[i] - result[i - 1]) / b; + } + + for (int i = 1; i < count; i++) + result[count - i - 1] -= temp[count - i] * result[count - i]; + + return result; +} + +//handlers + +void SplineChartItem::handleUpdated() +{ + setVisible(m_series->isVisible()); + setOpacity(m_series->opacity()); + m_pointsVisible = m_series->pointsVisible(); + m_linePen = m_series->pen(); + m_pointPen = m_series->pen(); + m_pointPen.setWidthF(2 * m_pointPen.width()); + m_pointLabelsFormat = m_series->pointLabelsFormat(); + m_pointLabelsVisible = m_series->pointLabelsVisible(); + m_pointLabelsFont = m_series->pointLabelsFont(); + m_pointLabelsColor = m_series->pointLabelsColor(); + update(); +} + +//painter + +void SplineChartItem::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); + painter->setBrush(Qt::NoBrush); + + 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_pathPolarLeft); + painter->setClipRegion(clipRegionRight); + painter->drawPath(m_pathPolarRight); + painter->setClipRegion(fullPolarClipRegion); + } else { + painter->setClipRect(clipRect); + } + + painter->drawPath(m_path); + + if (m_pointsVisible) { + painter->setPen(m_pointPen); + if (m_series->chart()->chartType() == QChart::ChartTypePolar) + painter->drawPoints(m_visiblePoints); + else + painter->drawPoints(geometryPoints()); + } + + if (m_pointLabelsVisible) + m_series->d_func()->drawSeriesPointLabels(painter, m_points, m_linePen.width() / 2); + + painter->restore(); +} + +void SplineChartItem::mousePressEvent(QGraphicsSceneMouseEvent *event) +{ + emit XYChart::clicked(domain()->calculateDomainPoint(event->pos())); + QGraphicsItem::mousePressEvent(event); +} + +void SplineChartItem::hoverEnterEvent(QGraphicsSceneHoverEvent *event) +{ + emit XYChart::hovered(domain()->calculateDomainPoint(event->pos()), true); + QGraphicsItem::hoverEnterEvent(event); +} + +void SplineChartItem::hoverLeaveEvent(QGraphicsSceneHoverEvent *event) +{ + emit XYChart::hovered(domain()->calculateDomainPoint(event->pos()), false); + QGraphicsItem::hoverLeaveEvent(event); +} + +#include "moc_splinechartitem_p.cpp" + +QT_CHARTS_END_NAMESPACE |