Qt 5.11 | Qt Data Visualization | Volumetric rendering Example | volumetric.cpp Example File

Qt Data Visualization | Commercial or GPLv3

# volumetric.cpp Example File

volumetric/volumetric.cpp

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      ** Contact: https://www.qt.io/licensing/
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      ** This file is part of the Qt Data Visualization module of the Qt Toolkit.
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      #include "volumetric.h"
      #include <QtDataVisualization/qvalue3daxis.h>
      #include <QtDataVisualization/q3dscene.h>
      #include <QtDataVisualization/q3dcamera.h>
      #include <QtDataVisualization/q3dtheme.h>
      #include <QtDataVisualization/qcustom3dlabel.h>
      #include <QtDataVisualization/q3dscatter.h>
      #include <QtDataVisualization/q3dinputhandler.h>
      #include <QtCore/qmath.h>
      #include <QtWidgets/QLabel>
      #include <QtWidgets/QRadioButton>
      #include <QtWidgets/QSlider>
      #include <QtCore/QDebug>
      #include <QtGui/QOpenGLContext>

      using namespace QtDataVisualization;

      const int lowDetailSize(128);
      const int mediumDetailSize(256);
      const int highDetailSize(512);
      const int colorTableSize(256);
      const int layerDataSize(512);
      const int mineShaftDiameter(1);

      const int airColorIndex(254);
      const int mineShaftColorIndex(255);
      const int layerColorThickness(60);
      const int heightToColorDiv(140);
      const int magmaColorsMin(0);
      const int magmaColorsMax(layerColorThickness);
      const int aboveWaterGroundColorsMin(magmaColorsMax + 1);
      const int aboveWaterGroundColorsMax(aboveWaterGroundColorsMin + layerColorThickness);
      const int underWaterGroundColorsMin(aboveWaterGroundColorsMax + 1);
      const int underWaterGroundColorsMax(underWaterGroundColorsMin + layerColorThickness);
      const int waterColorsMin(underWaterGroundColorsMax + 1);
      const int waterColorsMax(waterColorsMin + layerColorThickness);
      const int terrainTransparency(12);

      static bool isOpenGLES()
      {
      #if defined(QT_OPENGL_ES_2)
          return true;
      #elif (QT_VERSION < QT_VERSION_CHECK(5, 3, 0))
          return false;
      #else
          return QOpenGLContext::currentContext()->isOpenGLES();
      #endif
      }

      VolumetricModifier::VolumetricModifier(Q3DScatter *scatter)
          : m_graph(scatter),
            m_volumeItem(0),
            m_sliceIndexX(lowDetailSize / 2),
            m_sliceIndexY(lowDetailSize / 4),
            m_sliceIndexZ(lowDetailSize / 2),
            m_slicingX(false),
            m_slicingY(false),
            m_slicingZ(false),
            m_mediumDetailRB(0),
            m_highDetailRB(0),
            m_lowDetailData(0),
            m_mediumDetailData(0),
            m_highDetailData(0),
            m_mediumDetailIndex(0),
            m_highDetailIndex(0),
            m_mediumDetailShaftIndex(0),
            m_highDetailShaftIndex(0),
            m_sliceSliderX(0),
            m_sliceSliderY(0),
            m_sliceSliderZ(0),
            m_usingPrimaryTable(true),
            m_sliceLabelX(0),
            m_sliceLabelY(0),
            m_sliceLabelZ(0)
      {
          m_graph->activeTheme()->setType(Q3DTheme::ThemeQt);
          m_graph->setShadowQuality(QAbstract3DGraph::ShadowQualityNone);
          m_graph->scene()->activeCamera()->setCameraPreset(Q3DCamera::CameraPresetFront);
          m_graph->setOrthoProjection(true);
          m_graph->activeTheme()->setBackgroundEnabled(false);

          // Only allow zooming at the center and limit the zoom to 200% to avoid clipping issues
          static_cast<Q3DInputHandler *>(m_graph->activeInputHandler())->setZoomAtTargetEnabled(false);
          m_graph->scene()->activeCamera()->setMaxZoomLevel(200.0f);

          toggleAreaAll(true);

          if (!isOpenGLES()) {
              m_lowDetailData = new QVector<uchar>(lowDetailSize * lowDetailSize * lowDetailSize / 2);
              m_mediumDetailData = new QVector<uchar>(mediumDetailSize * mediumDetailSize * mediumDetailSize / 2);
              m_highDetailData = new QVector<uchar>(highDetailSize * highDetailSize * highDetailSize / 2);

              initHeightMap(QStringLiteral(":/heightmaps/layer_ground.png"), m_groundLayer);
              initHeightMap(QStringLiteral(":/heightmaps/layer_water.png"), m_waterLayer);
              initHeightMap(QStringLiteral(":/heightmaps/layer_magma.png"), m_magmaLayer);

              initMineShaftArray();

              createVolume(lowDetailSize, 0, lowDetailSize, m_lowDetailData);
              excavateMineShaft(lowDetailSize, 0, m_mineShaftArray.size(), m_lowDetailData);

              m_volumeItem = new QCustom3DVolume;
              // Adjust water level to zero with a minor tweak to y-coordinate position and scaling
              m_volumeItem->setScaling(
                          QVector3D(m_graph->axisX()->max() - m_graph->axisX()->min(),
                                    (m_graph->axisY()->max() - m_graph->axisY()->min()) * 0.91f,
                                    m_graph->axisZ()->max() - m_graph->axisZ()->min()));
              m_volumeItem->setPosition(
                          QVector3D((m_graph->axisX()->max() + m_graph->axisX()->min()) / 2.0f,
                                    -0.045f * (m_graph->axisY()->max() - m_graph->axisY()->min()) +
                                    (m_graph->axisY()->max() + m_graph->axisY()->min()) / 2.0f,
                                    (m_graph->axisZ()->max() + m_graph->axisZ()->min()) / 2.0f));
              m_volumeItem->setScalingAbsolute(false);
              m_volumeItem->setTextureWidth(lowDetailSize);
              m_volumeItem->setTextureHeight(lowDetailSize / 2);
              m_volumeItem->setTextureDepth(lowDetailSize);
              m_volumeItem->setTextureFormat(QImage::Format_Indexed8);
              m_volumeItem->setTextureData(new QVector<uchar>(*m_lowDetailData));

              // Generate color tables.
              m_colorTable1.resize(colorTableSize);
              m_colorTable2.resize(colorTableSize);

              for (int i = 0; i < colorTableSize - 2; i++) {
                  if (i < magmaColorsMax) {
                      m_colorTable1[i] = qRgba(130 - (i * 2), 0, 0, 255);
                  } else if (i < aboveWaterGroundColorsMax) {
                      m_colorTable1[i] = qRgba((i - magmaColorsMax) * 4,
                                               ((i - magmaColorsMax) * 2) + 120,
                                               (i - magmaColorsMax) * 5, terrainTransparency);
                  } else if (i < underWaterGroundColorsMax) {
                      m_colorTable1[i] = qRgba(((layerColorThickness - i - aboveWaterGroundColorsMax)) + 70,
                                               ((layerColorThickness - i - aboveWaterGroundColorsMax) * 2) + 20,
                                               ((layerColorThickness - i - aboveWaterGroundColorsMax)) + 50,
                                               terrainTransparency);
                  } else if (i < waterColorsMax) {
                      m_colorTable1[i] = qRgba(0, 0, ((i - underWaterGroundColorsMax) * 2) + 120,
                                               terrainTransparency);
                  } else {
                      m_colorTable1[i] = qRgba(0, 0, 0, 0); // Not used
                  }
              }
              m_colorTable1[airColorIndex] = qRgba(0, 0, 0, 0);
              m_colorTable1[mineShaftColorIndex] = qRgba(50, 50, 50, 255);

              // The alternate color table just has gray gradients for all terrain except water
              for (int i = 0; i < colorTableSize - 2; i++) {
                  if (i < magmaColorsMax) {
                      m_colorTable2[i] = qRgba(((i - aboveWaterGroundColorsMax) * 2),
                                               ((i - aboveWaterGroundColorsMax) * 2),
                                               ((i - aboveWaterGroundColorsMax) * 2), 255);
                  } else if (i < underWaterGroundColorsMax) {
                      m_colorTable2[i] = qRgba(((i - aboveWaterGroundColorsMax) * 2),
                                               ((i - aboveWaterGroundColorsMax) * 2),
                                               ((i - aboveWaterGroundColorsMax) * 2), terrainTransparency);
                  } else if (i < waterColorsMax) {
                      m_colorTable2[i] = qRgba(0, 0, ((i - underWaterGroundColorsMax) * 2) + 120,
                                               terrainTransparency);
                  } else {
                      m_colorTable2[i] = qRgba(0, 0, 0, 0); // Not used
                  }
              }
              m_colorTable2[airColorIndex] = qRgba(0, 0, 0, 0);
              m_colorTable2[mineShaftColorIndex] = qRgba(255, 255, 0, 255);

              m_volumeItem->setColorTable(m_colorTable1);

              m_volumeItem->setSliceFrameGaps(QVector3D(0.01f, 0.02f, 0.01f));
              m_volumeItem->setSliceFrameThicknesses(QVector3D(0.0025f, 0.005f, 0.0025f));
              m_volumeItem->setSliceFrameWidths(QVector3D(0.0025f, 0.005f, 0.0025f));
              m_volumeItem->setDrawSliceFrames(false);
              handleSlicingChanges();

              m_graph->addCustomItem(m_volumeItem);

              m_timer.start(0);
          } else {
              // OpenGL ES2 doesn't support 3D textures, so show a warning label instead
              QCustom3DLabel *warningLabel = new QCustom3DLabel(
                          "QCustom3DVolume is not supported with OpenGL ES2",
                          QFont(),
                          QVector3D(0.0f, 0.5f, 0.0f),
                          QVector3D(1.5f, 1.5f, 0.0f),
                          QQuaternion());
              warningLabel->setPositionAbsolute(true);
              warningLabel->setFacingCamera(true);
              m_graph->addCustomItem(warningLabel);
          }

          QObject::connect(m_graph, &QAbstract3DGraph::currentFpsChanged, this,
                           &VolumetricModifier::handleFpsChange);
          QObject::connect(&m_timer, &QTimer::timeout, this,
                           &VolumetricModifier::handleTimeout);

      }

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

      void VolumetricModifier::setFpsLabel(QLabel *fpsLabel)
      {
          m_fpsLabel = fpsLabel;
      }

      void VolumetricModifier::setMediumDetailRB(QRadioButton *button)
      {
          m_mediumDetailRB = button;
      }

      void VolumetricModifier::setHighDetailRB(QRadioButton *button)
      {
          m_highDetailRB = button;
      }

      void VolumetricModifier::setSliceLabels(QLabel *xLabel, QLabel *yLabel, QLabel *zLabel)
      {
          m_sliceLabelX = xLabel;
          m_sliceLabelY = yLabel;
          m_sliceLabelZ = zLabel;

          adjustSliceX(m_sliceSliderX->value());
          adjustSliceY(m_sliceSliderY->value());
          adjustSliceZ(m_sliceSliderZ->value());
      }

      void VolumetricModifier::setAlphaMultiplierLabel(QLabel *label)
      {
          m_alphaMultiplierLabel = label;
      }

      void VolumetricModifier::sliceX(int enabled)
      {
          m_slicingX = enabled;
          handleSlicingChanges();
      }

      void VolumetricModifier::sliceY(int enabled)
      {
          m_slicingY = enabled;
          handleSlicingChanges();
      }

      void VolumetricModifier::sliceZ(int enabled)
      {
          m_slicingZ = enabled;
          handleSlicingChanges();
      }

      void VolumetricModifier::adjustSliceX(int value)
      {
          if (m_volumeItem) {
              m_sliceIndexX = value / (1024 / m_volumeItem->textureWidth());
              if (m_sliceIndexX == m_volumeItem->textureWidth())
                  m_sliceIndexX--;
              if (m_volumeItem->sliceIndexX() != -1)
                  m_volumeItem->setSliceIndexX(m_sliceIndexX);
              m_sliceLabelX->setPixmap(
                          QPixmap::fromImage(m_volumeItem->renderSlice(Qt::XAxis, m_sliceIndexX)));
          }
      }

      void VolumetricModifier::adjustSliceY(int value)
      {
          if (m_volumeItem) {
              m_sliceIndexY = value / (1024 / m_volumeItem->textureHeight());
              if (m_sliceIndexY == m_volumeItem->textureHeight())
                  m_sliceIndexY--;
              if (m_volumeItem->sliceIndexY() != -1)
                  m_volumeItem->setSliceIndexY(m_sliceIndexY);
              m_sliceLabelY->setPixmap(
                          QPixmap::fromImage(m_volumeItem->renderSlice(Qt::YAxis, m_sliceIndexY)));
          }
      }

      void VolumetricModifier::adjustSliceZ(int value)
      {
          if (m_volumeItem) {
              m_sliceIndexZ = value / (1024 / m_volumeItem->textureDepth());
              if (m_sliceIndexZ == m_volumeItem->textureDepth())
                  m_sliceIndexZ--;
              if (m_volumeItem->sliceIndexZ() != -1)
                  m_volumeItem->setSliceIndexZ(m_sliceIndexZ);
              m_sliceLabelZ->setPixmap(
                          QPixmap::fromImage(m_volumeItem->renderSlice(Qt::ZAxis, m_sliceIndexZ)));
          }
      }

      void VolumetricModifier::handleFpsChange(qreal fps)
      {
          const QString fpsFormat = QStringLiteral("FPS: %1");
          int fps10 = int(fps * 10.0);
          m_fpsLabel->setText(fpsFormat.arg(qreal(fps10) / 10.0));
      }

      void VolumetricModifier::handleTimeout()
      {
          if (!m_mediumDetailRB->isEnabled()) {
              if (m_mediumDetailIndex != mediumDetailSize) {
                  m_mediumDetailIndex = createVolume(mediumDetailSize, m_mediumDetailIndex, 4,
                                                     m_mediumDetailData);
              } else if (m_mediumDetailShaftIndex != m_mineShaftArray.size()) {
                  m_mediumDetailShaftIndex = excavateMineShaft(mediumDetailSize, m_mediumDetailShaftIndex,
                                                               1, m_mediumDetailData );
              } else {
                  m_mediumDetailRB->setEnabled(true);
                  QString label = QStringLiteral("Medium (%1x%2x%1)");
                  m_mediumDetailRB->setText(label.arg(mediumDetailSize).arg(mediumDetailSize / 2));
              }
          } else if (!m_highDetailRB->isEnabled()) {
              if (m_highDetailIndex != highDetailSize) {
                  m_highDetailIndex = createVolume(highDetailSize, m_highDetailIndex, 1,
                                                   m_highDetailData);
              } else if (m_highDetailShaftIndex != m_mineShaftArray.size()) {
                  m_highDetailShaftIndex = excavateMineShaft(highDetailSize, m_highDetailShaftIndex, 1,
                                                             m_highDetailData);
              } else  {
                  m_highDetailRB->setEnabled(true);
                  QString label = QStringLiteral("High (%1x%2x%1)");
                  m_highDetailRB->setText(label.arg(highDetailSize).arg(highDetailSize / 2));
                  m_timer.stop();
              }
          }
      }

      void VolumetricModifier::toggleLowDetail(bool enabled)
      {
          if (enabled && m_volumeItem) {
              m_volumeItem->setTextureData(new QVector<uchar>(*m_lowDetailData));
              m_volumeItem->setTextureDimensions(lowDetailSize, lowDetailSize / 2, lowDetailSize);
              adjustSliceX(m_sliceSliderX->value());
              adjustSliceY(m_sliceSliderY->value());
              adjustSliceZ(m_sliceSliderZ->value());
          }
      }

      void VolumetricModifier::toggleMediumDetail(bool enabled)
      {
          if (enabled && m_volumeItem) {
              m_volumeItem->setTextureData(new QVector<uchar>(*m_mediumDetailData));
              m_volumeItem->setTextureDimensions(mediumDetailSize, mediumDetailSize / 2, mediumDetailSize);
              adjustSliceX(m_sliceSliderX->value());
              adjustSliceY(m_sliceSliderY->value());
              adjustSliceZ(m_sliceSliderZ->value());
          }
      }

      void VolumetricModifier::toggleHighDetail(bool enabled)
      {
          if (enabled && m_volumeItem) {
              m_volumeItem->setTextureData(new QVector<uchar>(*m_highDetailData));
              m_volumeItem->setTextureDimensions(highDetailSize, highDetailSize / 2, highDetailSize);
              adjustSliceX(m_sliceSliderX->value());
              adjustSliceY(m_sliceSliderY->value());
              adjustSliceZ(m_sliceSliderZ->value());
          }
      }

      void VolumetricModifier::setFpsMeasurement(bool enabled)
      {
          m_graph->setMeasureFps(enabled);
          if (enabled)
              m_fpsLabel->setText(QStringLiteral("Measuring..."));
          else
              m_fpsLabel->setText(QString());
      }

      void VolumetricModifier::setSliceSliders(QSlider *sliderX, QSlider *sliderY, QSlider *sliderZ)
      {
          m_sliceSliderX = sliderX;
          m_sliceSliderY = sliderY;
          m_sliceSliderZ = sliderZ;

          // Set sliders to interesting values
          m_sliceSliderX->setValue(715);
          m_sliceSliderY->setValue(612);
          m_sliceSliderZ->setValue(715);
      }

      void VolumetricModifier::changeColorTable(int enabled)
      {
          if (m_volumeItem) {
              if (enabled)
                  m_volumeItem->setColorTable(m_colorTable2);
              else
                  m_volumeItem->setColorTable(m_colorTable1);

              m_usingPrimaryTable = !enabled;

              // Rerender image labels
              adjustSliceX(m_sliceSliderX->value());
              adjustSliceY(m_sliceSliderY->value());
              adjustSliceZ(m_sliceSliderZ->value());
          }
      }

      void VolumetricModifier::setPreserveOpacity(bool enabled)
      {

          if (m_volumeItem) {
              m_volumeItem->setPreserveOpacity(enabled);

              // Rerender image labels
              adjustSliceX(m_sliceSliderX->value());
              adjustSliceY(m_sliceSliderY->value());
              adjustSliceZ(m_sliceSliderZ->value());
          }
      }

      void VolumetricModifier::setTransparentGround(bool enabled)
      {
          if (m_volumeItem) {
              int newAlpha = enabled ? terrainTransparency : 255;
              for (int i = aboveWaterGroundColorsMin; i < underWaterGroundColorsMax; i++) {
                  QRgb oldColor1 = m_colorTable1.at(i);
                  QRgb oldColor2 = m_colorTable2.at(i);
                  m_colorTable1[i] = qRgba(qRed(oldColor1), qGreen(oldColor1), qBlue(oldColor1), newAlpha);
                  m_colorTable2[i] = qRgba(qRed(oldColor2), qGreen(oldColor2), qBlue(oldColor2), newAlpha);
              }
              if (m_usingPrimaryTable)
                  m_volumeItem->setColorTable(m_colorTable1);
              else
                  m_volumeItem->setColorTable(m_colorTable2);
              adjustSliceX(m_sliceSliderX->value());
              adjustSliceY(m_sliceSliderY->value());
              adjustSliceZ(m_sliceSliderZ->value());
          }
      }

      void VolumetricModifier::setUseHighDefShader(bool enabled)
      {
          if (m_volumeItem) {
              m_volumeItem->setUseHighDefShader(enabled);
          }
      }

      void VolumetricModifier::adjustAlphaMultiplier(int value)
      {
          if (m_volumeItem) {
              float mult;
              if (value > 100)
                  mult = float(value - 99) / 2.0f;
              else
                  mult = float(value) / float(500 - value * 4);
              m_volumeItem->setAlphaMultiplier(mult);
              QString labelFormat = QStringLiteral("Alpha multiplier: %1");
              m_alphaMultiplierLabel->setText(labelFormat.arg(
                                                  QString::number(m_volumeItem->alphaMultiplier(), 'f', 3)));

              // Rerender image labels
              adjustSliceX(m_sliceSliderX->value());
              adjustSliceY(m_sliceSliderY->value());
              adjustSliceZ(m_sliceSliderZ->value());
          }
      }

      void VolumetricModifier::toggleAreaAll(bool enabled)
      {
          if (enabled) {
              m_graph->axisX()->setRange(0.0f, 1000.0f);
              m_graph->axisY()->setRange(-600.0f, 600.0f);
              m_graph->axisZ()->setRange(0.0f, 1000.0f);
              m_graph->axisX()->setSegmentCount(5);
              m_graph->axisY()->setSegmentCount(6);
              m_graph->axisZ()->setSegmentCount(5);
          }
      }

      void VolumetricModifier::toggleAreaMine(bool enabled)
      {
          if (enabled) {
              m_graph->axisX()->setRange(350.0f, 850.0f);
              m_graph->axisY()->setRange(-500.0f, 100.0f);
              m_graph->axisZ()->setRange(350.0f, 900.0f);
              m_graph->axisX()->setSegmentCount(10);
              m_graph->axisY()->setSegmentCount(6);
              m_graph->axisZ()->setSegmentCount(11);
          }
      }

      void VolumetricModifier::toggleAreaMountain(bool enabled)
      {
          if (enabled) {
              m_graph->axisX()->setRange(300.0f, 600.0f);
              m_graph->axisY()->setRange(-100.0f, 400.0f);
              m_graph->axisZ()->setRange(300.0f, 600.0f);
              m_graph->axisX()->setSegmentCount(9);
              m_graph->axisY()->setSegmentCount(5);
              m_graph->axisZ()->setSegmentCount(9);
          }
      }

      void VolumetricModifier::setDrawSliceFrames(int enabled)
      {
          if (m_volumeItem)
              m_volumeItem->setDrawSliceFrames(enabled);
      }

      void VolumetricModifier::initHeightMap(QString fileName, QVector<uchar> &layerData)
      {
          QImage heightImage(fileName);

          layerData.resize(layerDataSize * layerDataSize);
          const uchar *bits = heightImage.bits();
          int index = 0;
          QVector<QRgb> colorTable = heightImage.colorTable();
          for (int i = 0; i < layerDataSize; i++) {
              for (int j = 0; j < layerDataSize; j++) {
                  layerData[index] = qRed(colorTable.at(bits[index]));
                  index++;
              }
          }
      }

      int VolumetricModifier::createVolume(int textureSize, int startIndex, int count,
                                           QVector<uchar> *textureData)
      {
          // Generate volume from layer data.
          int index = startIndex * textureSize * textureSize / 2.0f;
          int endIndex = startIndex + count;
          if (endIndex > textureSize)
              endIndex = textureSize;
          QVector<uchar> magmaHeights(textureSize);
          QVector<uchar> waterHeights(textureSize);
          QVector<uchar> groundHeights(textureSize);
          float multiplier = float(layerDataSize) / float(textureSize);
          for (int i = startIndex; i < endIndex; i++) {
              // Generate layer height arrays
              for (int l = 0; l < textureSize; l++) {
                  int layerIndex = (int(i * multiplier) * layerDataSize + int(l * multiplier));
                  magmaHeights[l] = int(m_magmaLayer.at(layerIndex));
                  waterHeights[l] = int(m_waterLayer.at(layerIndex));
                  groundHeights[l] = int(m_groundLayer.at(layerIndex));
              }
              for (int j = 0; j < textureSize / 2; j++) {
                  for (int k = 0; k < textureSize; k++) {
                      int colorIndex;
                      int height((layerDataSize - (j * 2 * multiplier)) / 2);
                      if (height < magmaHeights.at(k)) {
                          // Magma layer
                          colorIndex = int((float(height) / heightToColorDiv)
                                           * float(layerColorThickness)) + magmaColorsMin;
                      } else if (height < groundHeights.at(k) && height < waterHeights.at(k)) {
                          // Ground layer below water
                          colorIndex = int((float(waterHeights.at(k) - height) / heightToColorDiv)
                                           * float(layerColorThickness)) + underWaterGroundColorsMin;
                      } else if (height < waterHeights.at(k)) {
                          // Water layer where water goes over ground
                          colorIndex = int((float(height - magmaHeights.at(k)) / heightToColorDiv)
                                           * float(layerColorThickness)) + waterColorsMin;
                      } else if (height <= groundHeights.at(k)) {
                          // Ground above water
                          colorIndex = int((float(height - waterHeights.at(k)) / heightToColorDiv)
                                           * float(layerColorThickness)) + aboveWaterGroundColorsMin;
                      } else {
                          // Rest is air
                          colorIndex = airColorIndex;
                      }

                      (*textureData)[index] = colorIndex;
                      index++;
                  }
              }
          }
          return endIndex;
      }

      int VolumetricModifier::excavateMineShaft(int textureSize, int startIndex, int count,
                                                QVector<uchar> *textureData)
      {
          int endIndex = startIndex + count;
          if (endIndex > m_mineShaftArray.size())
              endIndex = m_mineShaftArray.size();
          int shaftSize = mineShaftDiameter * textureSize / lowDetailSize;
          for (int i = startIndex; i < endIndex; i++) {
              QVector3D shaftStart(m_mineShaftArray.at(i).first);
              QVector3D shaftEnd(m_mineShaftArray.at(i).second);
              int shaftLen = (shaftEnd - shaftStart).length() * lowDetailSize;
              int dataX = shaftStart.x() * textureSize - (shaftSize / 2);
              int dataY = (shaftStart.y() * textureSize - (shaftSize / 2)) / 2;
              int dataZ = shaftStart.z() * textureSize - (shaftSize / 2);
              int dataIndex = dataX + (dataY * textureSize) + dataZ * (textureSize * textureSize / 2);
              if (shaftStart.x() != shaftEnd.x()) {
                  for (int j = 0; j <= shaftLen; j++) {
                      excavateMineBlock(textureSize, dataIndex, shaftSize, textureData);
                      dataIndex += shaftSize;
                  }
              } else if (shaftStart.y() != shaftEnd.y()) {
                  shaftLen /= 2; // Vertical shafts are half as long
                  for (int j = 0; j <= shaftLen; j++) {
                      excavateMineBlock(textureSize, dataIndex, shaftSize, textureData);
                      dataIndex += textureSize * shaftSize;
                  }
              } else {
                  for (int j = 0; j <= shaftLen; j++) {
                      excavateMineBlock(textureSize, dataIndex, shaftSize, textureData);
                      dataIndex += (textureSize * textureSize / 2) * shaftSize;
                  }
              }

          }
          return endIndex;
      }

      void VolumetricModifier::excavateMineBlock(int textureSize, int dataIndex, int size,
                                                 QVector<uchar> *textureData)
      {
          for (int k = 0; k < size; k++) {
              int curIndex = dataIndex + (k * textureSize * textureSize / 2);
              for (int l = 0; l < size; l++) {
                  curIndex = dataIndex + (k * textureSize * textureSize / 2)
                          + (l * textureSize);
                  for (int m = 0; m < size; m++) {
                      if (textureData->at(curIndex) != airColorIndex)
                          (*textureData)[curIndex] = mineShaftColorIndex;
                      curIndex++;
                  }

              }
          }
      }

      void VolumetricModifier::handleSlicingChanges()
      {
          if (m_volumeItem) {
              if (m_slicingX || m_slicingY || m_slicingZ) {
                  // Only show slices of selected dimensions
                  m_volumeItem->setDrawSlices(true);
                  m_volumeItem->setSliceIndexX(m_slicingX ? m_sliceIndexX : -1);
                  m_volumeItem->setSliceIndexY(m_slicingY ? m_sliceIndexY : -1);
                  m_volumeItem->setSliceIndexZ(m_slicingZ ? m_sliceIndexZ : -1);
              } else {
                  // Show slice frames for all dimenstions when not actually slicing
                  m_volumeItem->setDrawSlices(false);
                  m_volumeItem->setSliceIndexX(m_sliceIndexX);
                  m_volumeItem->setSliceIndexY(m_sliceIndexY);
                  m_volumeItem->setSliceIndexZ(m_sliceIndexZ);
              }
          }
      }

      void VolumetricModifier::initMineShaftArray()
      {
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.7f, 0.1f, 0.7f),
                                                          QVector3D(0.7f, 0.8f, 0.7f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.7f, 0.7f, 0.5f),
                                                          QVector3D(0.7f, 0.7f, 0.7f));

          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.4f, 0.7f, 0.7f),
                                                          QVector3D(0.7f, 0.7f, 0.7f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.4f, 0.7f, 0.7f),
                                                          QVector3D(0.4f, 0.7f, 0.8f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.45f, 0.7f, 0.7f),
                                                          QVector3D(0.45f, 0.7f, 0.8f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.5f, 0.7f, 0.7f),
                                                          QVector3D(0.5f, 0.7f, 0.8f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.55f, 0.7f, 0.7f),
                                                          QVector3D(0.55f, 0.7f, 0.8f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.7f, 0.7f),
                                                          QVector3D(0.6f, 0.7f, 0.8f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.65f, 0.7f, 0.7f),
                                                          QVector3D(0.65f, 0.7f, 0.8f));

          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.5f, 0.6f, 0.7f),
                                                          QVector3D(0.7f, 0.6f, 0.7f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.5f, 0.6f, 0.7f),
                                                          QVector3D(0.5f, 0.6f, 0.8f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.55f, 0.6f, 0.7f),
                                                          QVector3D(0.55f, 0.6f, 0.8f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.6f, 0.7f),
                                                          QVector3D(0.6f, 0.6f, 0.8f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.65f, 0.6f, 0.7f),
                                                          QVector3D(0.65f, 0.6f, 0.8f));

          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.7f, 0.6f, 0.4f),
                                                          QVector3D(0.7f, 0.6f, 0.7f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.6f, 0.45f),
                                                          QVector3D(0.8f, 0.6f, 0.45f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.6f, 0.5f),
                                                          QVector3D(0.8f, 0.6f, 0.5f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.6f, 0.55f),
                                                          QVector3D(0.8f, 0.6f, 0.55f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.6f, 0.6f),
                                                          QVector3D(0.8f, 0.6f, 0.6f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.6f, 0.65f),
                                                          QVector3D(0.8f, 0.6f, 0.65f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.6f, 0.7f),
                                                          QVector3D(0.8f, 0.6f, 0.7f));

          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.7f, 0.7f, 0.4f),
                                                          QVector3D(0.7f, 0.7f, 0.7f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.7f, 0.45f),
                                                          QVector3D(0.8f, 0.7f, 0.45f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.7f, 0.5f),
                                                          QVector3D(0.8f, 0.7f, 0.5f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.7f, 0.55f),
                                                          QVector3D(0.8f, 0.7f, 0.55f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.7f, 0.6f),
                                                          QVector3D(0.8f, 0.7f, 0.6f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.7f, 0.65f),
                                                          QVector3D(0.8f, 0.7f, 0.65f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.7f, 0.7f),
                                                          QVector3D(0.8f, 0.7f, 0.7f));

          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.7f, 0.8f, 0.5f),
                                                          QVector3D(0.7f, 0.8f, 0.7f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.8f, 0.55f),
                                                          QVector3D(0.8f, 0.8f, 0.55f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.8f, 0.6f),
                                                          QVector3D(0.8f, 0.8f, 0.6f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.8f, 0.65f),
                                                          QVector3D(0.8f, 0.8f, 0.65f));
          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.6f, 0.8f, 0.7f),
                                                          QVector3D(0.8f, 0.8f, 0.7f));

          m_mineShaftArray << QPair<QVector3D, QVector3D>(QVector3D(0.7f, 0.1f, 0.4f),
                                                          QVector3D(0.7f, 0.7f, 0.4f));
      }