- Qt 6.7
- Qt Graphs
- Volumetric Rendering
- Qt Graphs | Commercial or GPLv3

# Volumetric Rendering

     // Copyright (C) 2023 The Qt Company Ltd.
     // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

     #include "volumetric.h"
     #include <QtGraphs/qvalue3daxis.h>
     #include <QtGraphs/qcustom3dlabel.h>
     #include <QtGraphs/q3dinputhandler.h>
     #include <QtCore/qmath.h>

     const int lowDetailSize(256);
     const int mediumDetailSize(512);
     const int highDetailSize(1024);
     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);

     VolumetricModifier::VolumetricModifier(Q3DScatter *scatter)
         : m_graph(scatter),
           m_sliceIndexX(lowDetailSize / 2),
           m_sliceIndexY(lowDetailSize / 4),
           m_sliceIndexZ(lowDetailSize / 2)
     {
         m_graph->activeTheme()->setType(Q3DTheme::Theme::PrimaryColors);
         m_graph->setShadowQuality(QAbstract3DGraph::ShadowQuality::None);
         m_graph->setCameraPreset(QAbstract3DGraph::CameraPreset::IsometricLeft);
         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->setMaxCameraZoomLevel(200.0f);

         toggleAreaAll(true);

         m_lowDetailData
                 = new QList<uchar>(lowDetailSize * lowDetailSize * lowDetailSize / 2);
         m_mediumDetailData
                 = new QList<uchar>(mediumDetailSize * mediumDetailSize * mediumDetailSize / 2);
         m_highDetailData
                 = new QList<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 QList<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);

         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 QList<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 QList<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 QList<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::setUsePerspectiveCamera(bool enabled)
     {
         if (m_graph)
             m_graph->setOrthoProjection(!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, QList<uchar> &layerData)
     {
         QImage heightImage(fileName);

         layerData.resize(layerDataSize * layerDataSize);
         const uchar *bits = heightImage.bits();
         int index = 0;
         QList<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,
                                          QList<uchar> *textureData)
     {
         // Generate volume from layer data.
         int index = startIndex * textureSize * textureSize / 2.0f;
         int endIndex = startIndex + count;
         if (endIndex > textureSize)
             endIndex = textureSize;
         QList<uchar> magmaHeights(textureSize);
         QList<uchar> waterHeights(textureSize);
         QList<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,
                                               QList<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,
                                                QList<uchar> *textureData)
     {
         for (int k = 0; k < size; k++) {
             int curIndex = 0;
             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));
     }