Surface Example

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 #include "surfacegraph.h"

 #include <QtDataVisualization/QValue3DAxis>
 #include <QtDataVisualization/Q3DTheme>
 #include <QtGui/QImage>
 #include <QtCore/qmath.h>

 using namespace QtDataVisualization;

 const int sampleCountX = 50;
 const int sampleCountZ = 50;
 const int heightMapGridStepX = 6;
 const int heightMapGridStepZ = 6;
 const float sampleMin = -8.0f;
 const float sampleMax = 8.0f;

 SurfaceGraph::SurfaceGraph(Q3DSurface *surface)
     : m_graph(surface)
 {
     m_graph->setAxisX(new QValue3DAxis);
     m_graph->setAxisY(new QValue3DAxis);
     m_graph->setAxisZ(new QValue3DAxis);

     m_sqrtSinProxy = new QSurfaceDataProxy();
     m_sqrtSinSeries = new QSurface3DSeries(m_sqrtSinProxy);
     fillSqrtSinProxy();

     QImage heightMapImage(":/maps/mountain");
     m_heightMapProxy = new QHeightMapSurfaceDataProxy(heightMapImage);
     m_heightMapSeries = new QSurface3DSeries(m_heightMapProxy);
     m_heightMapSeries->setItemLabelFormat(QStringLiteral("(@xLabel, @zLabel): @yLabel"));
     m_heightMapProxy->setValueRanges(34.0f, 40.0f, 18.0f, 24.0f);
     m_heightMapWidth = heightMapImage.width();
     m_heightMapHeight = heightMapImage.height();
 }

 SurfaceGraph::~SurfaceGraph()
 {
     delete m_graph;
 }

 void SurfaceGraph::fillSqrtSinProxy()
 {
     float stepX = (sampleMax - sampleMin) / float(sampleCountX - 1);
     float stepZ = (sampleMax - sampleMin) / float(sampleCountZ - 1);

     QSurfaceDataArray *dataArray = new QSurfaceDataArray;
     dataArray->reserve(sampleCountZ);
     for (int i = 0 ; i < sampleCountZ ; i++) {
         QSurfaceDataRow *newRow = new QSurfaceDataRow(sampleCountX);
         // Keep values within range bounds, since just adding step can cause minor drift due
         // to the rounding errors.
         float z = qMin(sampleMax, (i * stepZ + sampleMin));
         int index = 0;
         for (int j = 0; j < sampleCountX; j++) {
             float x = qMin(sampleMax, (j * stepX + sampleMin));
             float R = qSqrt(z * z + x * x) + 0.01f;
             float y = (qSin(R) / R + 0.24f) * 1.61f;
             (*newRow)[index++].setPosition(QVector3D(x, y, z));
         }
         *dataArray << newRow;
     }

     m_sqrtSinProxy->resetArray(dataArray);
 }

 void SurfaceGraph::enableSqrtSinModel(bool enable)
 {
     if (enable) {
         m_sqrtSinSeries->setDrawMode(QSurface3DSeries::DrawSurfaceAndWireframe);
         m_sqrtSinSeries->setFlatShadingEnabled(true);

         m_graph->axisX()->setLabelFormat("%.2f");
         m_graph->axisZ()->setLabelFormat("%.2f");
         m_graph->axisX()->setRange(sampleMin, sampleMax);
         m_graph->axisY()->setRange(0.0f, 2.0f);
         m_graph->axisZ()->setRange(sampleMin, sampleMax);
         m_graph->axisX()->setLabelAutoRotation(30);
         m_graph->axisY()->setLabelAutoRotation(90);
         m_graph->axisZ()->setLabelAutoRotation(30);

         m_graph->removeSeries(m_heightMapSeries);
         m_graph->addSeries(m_sqrtSinSeries);

         // Reset range sliders for Sqrt&Sin
         m_rangeMinX = sampleMin;
         m_rangeMinZ = sampleMin;
         m_stepX = (sampleMax - sampleMin) / float(sampleCountX - 1);
         m_stepZ = (sampleMax - sampleMin) / float(sampleCountZ - 1);
         m_axisMinSliderX->setMaximum(sampleCountX - 2);
         m_axisMinSliderX->setValue(0);
         m_axisMaxSliderX->setMaximum(sampleCountX - 1);
         m_axisMaxSliderX->setValue(sampleCountX - 1);
         m_axisMinSliderZ->setMaximum(sampleCountZ - 2);
         m_axisMinSliderZ->setValue(0);
         m_axisMaxSliderZ->setMaximum(sampleCountZ - 1);
         m_axisMaxSliderZ->setValue(sampleCountZ - 1);
     }
 }

 void SurfaceGraph::enableHeightMapModel(bool enable)
 {
     if (enable) {
         m_heightMapSeries->setDrawMode(QSurface3DSeries::DrawSurface);
         m_heightMapSeries->setFlatShadingEnabled(false);

         m_graph->axisX()->setLabelFormat("%.1f N");
         m_graph->axisZ()->setLabelFormat("%.1f E");
         m_graph->axisX()->setRange(34.0f, 40.0f);
         m_graph->axisY()->setAutoAdjustRange(true);
         m_graph->axisZ()->setRange(18.0f, 24.0f);

         m_graph->axisX()->setTitle(QStringLiteral("Latitude"));
         m_graph->axisY()->setTitle(QStringLiteral("Height"));
         m_graph->axisZ()->setTitle(QStringLiteral("Longitude"));

         m_graph->removeSeries(m_sqrtSinSeries);
         m_graph->addSeries(m_heightMapSeries);

         // Reset range sliders for height map
         int mapGridCountX = m_heightMapWidth / heightMapGridStepX;
         int mapGridCountZ = m_heightMapHeight / heightMapGridStepZ;
         m_rangeMinX = 34.0f;
         m_rangeMinZ = 18.0f;
         m_stepX = 6.0f / float(mapGridCountX - 1);
         m_stepZ = 6.0f / float(mapGridCountZ - 1);
         m_axisMinSliderX->setMaximum(mapGridCountX - 2);
         m_axisMinSliderX->setValue(0);
         m_axisMaxSliderX->setMaximum(mapGridCountX - 1);
         m_axisMaxSliderX->setValue(mapGridCountX - 1);
         m_axisMinSliderZ->setMaximum(mapGridCountZ - 2);
         m_axisMinSliderZ->setValue(0);
         m_axisMaxSliderZ->setMaximum(mapGridCountZ - 1);
         m_axisMaxSliderZ->setValue(mapGridCountZ - 1);
     }
 }

 void SurfaceGraph::adjustXMin(int min)
 {
     float minX = m_stepX * float(min) + m_rangeMinX;

     int max = m_axisMaxSliderX->value();
     if (min >= max) {
         max = min + 1;
         m_axisMaxSliderX->setValue(max);
     }
     float maxX = m_stepX * max + m_rangeMinX;

     setAxisXRange(minX, maxX);
 }

 void SurfaceGraph::adjustXMax(int max)
 {
     float maxX = m_stepX * float(max) + m_rangeMinX;

     int min = m_axisMinSliderX->value();
     if (max <= min) {
         min = max - 1;
         m_axisMinSliderX->setValue(min);
     }
     float minX = m_stepX * min + m_rangeMinX;

     setAxisXRange(minX, maxX);
 }

 void SurfaceGraph::adjustZMin(int min)
 {
     float minZ = m_stepZ * float(min) + m_rangeMinZ;

     int max = m_axisMaxSliderZ->value();
     if (min >= max) {
         max = min + 1;
         m_axisMaxSliderZ->setValue(max);
     }
     float maxZ = m_stepZ * max + m_rangeMinZ;

     setAxisZRange(minZ, maxZ);
 }

 void SurfaceGraph::adjustZMax(int max)
 {
     float maxX = m_stepZ * float(max) + m_rangeMinZ;

     int min = m_axisMinSliderZ->value();
     if (max <= min) {
         min = max - 1;
         m_axisMinSliderZ->setValue(min);
     }
     float minX = m_stepZ * min + m_rangeMinZ;

     setAxisZRange(minX, maxX);
 }

 void SurfaceGraph::setAxisXRange(float min, float max)
 {
     m_graph->axisX()->setRange(min, max);
 }

 void SurfaceGraph::setAxisZRange(float min, float max)
 {
     m_graph->axisZ()->setRange(min, max);
 }

 void SurfaceGraph::changeTheme(int theme)
 {
     m_graph->activeTheme()->setType(Q3DTheme::Theme(theme));
 }

 void SurfaceGraph::setBlackToYellowGradient()
 {
     QLinearGradient gr;
     gr.setColorAt(0.0, Qt::black);
     gr.setColorAt(0.33, Qt::blue);
     gr.setColorAt(0.67, Qt::red);
     gr.setColorAt(1.0, Qt::yellow);

     m_graph->seriesList().at(0)->setBaseGradient(gr);
     m_graph->seriesList().at(0)->setColorStyle(Q3DTheme::ColorStyleRangeGradient);
 }

 void SurfaceGraph::setGreenToRedGradient()
 {
     QLinearGradient gr;
     gr.setColorAt(0.0, Qt::darkGreen);
     gr.setColorAt(0.5, Qt::yellow);
     gr.setColorAt(0.8, Qt::red);
     gr.setColorAt(1.0, Qt::darkRed);

     m_graph->seriesList().at(0)->setBaseGradient(gr);
     m_graph->seriesList().at(0)->setColorStyle(Q3DTheme::ColorStyleRangeGradient);
 }