/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd and/or its subsidiary(-ies).
** Contact: https://www.qt.io/licensing/
**
** This file is part of the Qt3D module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "gltfexporter.h"

#include <QtCore/qiodevice.h>
#include <QtCore/qfile.h>
#include <QtCore/qfileinfo.h>
#include <QtCore/qdir.h>
#include <QtCore/qhash.h>
#include <QtCore/qdebug.h>
#include <QtCore/qcoreapplication.h>
#include <QtCore/qjsondocument.h>
#include <QtCore/qjsonobject.h>
#include <QtCore/qjsonarray.h>
#include <QtCore/qmath.h>
#include <QtCore/qtemporarydir.h>
#include <QtCore/qregularexpression.h>
#include <QtCore/qmetaobject.h>
#include <QtGui/qvector2d.h>
#include <QtGui/qvector4d.h>
#include <QtGui/qmatrix4x4.h>

#include <Qt3DCore/qentity.h>
#include <Qt3DCore/qattribute.h>
#include <Qt3DCore/qbuffer.h>
#include <Qt3DCore/qgeometry.h>
#include <Qt3DCore/qtransform.h>
#include <Qt3DRender/qcameralens.h>
#include <Qt3DRender/qcamera.h>
#include <Qt3DRender/qblendequation.h>
#include <Qt3DRender/qblendequationarguments.h>
#include <Qt3DRender/qeffect.h>
#include <Qt3DRender/qmaterial.h>
#include <Qt3DRender/qgraphicsapifilter.h>
#include <Qt3DRender/qparameter.h>
#include <Qt3DRender/qtexture.h>
#include <Qt3DRender/qabstractlight.h>
#include <Qt3DRender/qpointlight.h>
#include <Qt3DRender/qspotlight.h>
#include <Qt3DRender/qdirectionallight.h>
#include <Qt3DRender/qgeometryrenderer.h>
#include <Qt3DRender/qtechnique.h>
#include <Qt3DRender/qalphacoverage.h>
#include <Qt3DRender/qalphatest.h>
#include <Qt3DRender/qclipplane.h>
#include <Qt3DRender/qcolormask.h>
#include <Qt3DRender/qcullface.h>
#include <Qt3DRender/qdepthrange.h>
#include <Qt3DRender/qdepthtest.h>
#include <Qt3DRender/qdithering.h>
#include <Qt3DRender/qfrontface.h>
#include <Qt3DRender/qmultisampleantialiasing.h>
#include <Qt3DRender/qnodepthmask.h>
#include <Qt3DRender/qpointsize.h>
#include <Qt3DRender/qpolygonoffset.h>
#include <Qt3DRender/qscissortest.h>
#include <Qt3DRender/qseamlesscubemap.h>
#include <Qt3DRender/qstencilmask.h>
#include <Qt3DRender/qstenciloperation.h>
#include <Qt3DRender/qstenciloperationarguments.h>
#include <Qt3DRender/qstenciltest.h>
#include <Qt3DRender/qstenciltestarguments.h>
#include <Qt3DExtras/qconemesh.h>
#include <Qt3DExtras/qcuboidmesh.h>
#include <Qt3DExtras/qcylindermesh.h>
#include <Qt3DExtras/qplanemesh.h>
#include <Qt3DExtras/qspheremesh.h>
#include <Qt3DExtras/qtorusmesh.h>
#include <Qt3DExtras/qphongmaterial.h>
#include <Qt3DExtras/qphongalphamaterial.h>
#include <Qt3DExtras/qdiffusemapmaterial.h>
#include <Qt3DExtras/qdiffusespecularmapmaterial.h>
#include <Qt3DExtras/qnormaldiffusemapmaterial.h>
#include <Qt3DExtras/qnormaldiffusemapalphamaterial.h>
#include <Qt3DExtras/qnormaldiffusespecularmapmaterial.h>
#include <Qt3DExtras/qgoochmaterial.h>
#include <Qt3DExtras/qpervertexcolormaterial.h>

#include <private/qurlhelper_p.h>

#ifndef qUtf16PrintableImpl
#  define qUtf16PrintableImpl(string) \
    static_cast<const wchar_t*>(static_cast<const void*>(string.utf16()))
#endif

namespace {

inline QJsonArray col2jsvec(const QColor &color, bool alpha = false)
{
    QJsonArray arr;
    arr << color.redF() << color.greenF() << color.blueF();
    if (alpha)
        arr << color.alphaF();
    return arr;
}

template <typename T>
inline QJsonArray vec2jsvec(const QVector<T> &v)
{
    QJsonArray arr;
    for (int i = 0; i < v.count(); ++i)
        arr << v.at(i);
    return arr;
}

inline QJsonArray size2jsvec(const QSize &size) {
    QJsonArray arr;
    arr << size.width() << size.height();
    return arr;
}

inline QJsonArray vec2jsvec(const QVector2D &v)
{
    QJsonArray arr;
    arr << v.x() << v.y();
    return arr;
}

inline QJsonArray vec2jsvec(const QVector3D &v)
{
    QJsonArray arr;
    arr << v.x() << v.y() << v.z();
    return arr;
}

inline QJsonArray vec2jsvec(const QVector4D &v)
{
    QJsonArray arr;
    arr << v.x() << v.y() << v.z() << v.w();
    return arr;
}

#if 0   // unused for now
inline QJsonArray matrix2jsvec(const QMatrix2x2 &matrix)
{
    QJsonArray jm;
    const float *mtxp = matrix.constData();
    for (int j = 0; j < 4; ++j)
        jm.append(*mtxp++);
    return jm;
}

inline QJsonArray matrix2jsvec(const QMatrix3x3 &matrix)
{
    QJsonArray jm;
    const float *mtxp = matrix.constData();
    for (int j = 0; j < 9; ++j)
        jm.append(*mtxp++);
    return jm;
}
#endif

inline QJsonArray matrix2jsvec(const QMatrix4x4 &matrix)
{
    QJsonArray jm;
    const float *mtxp = matrix.constData();
    for (int j = 0; j < 16; ++j)
        jm.append(*mtxp++);
    return jm;
}

inline void promoteColorsToRGBA(QJsonObject *obj)
{
    auto it = obj->begin();
    auto itEnd = obj->end();
    while (it != itEnd) {
        QJsonArray arr = it.value().toArray();
        if (arr.count() == 3) {
            const QString key = it.key();
            if (key == QStringLiteral("ambient")
                    || key == QStringLiteral("diffuse")
                    || key == QStringLiteral("specular")
                    || key == QStringLiteral("warm")
                    || key == QStringLiteral("cool")) {
                arr.append(1);
                *it = arr;
            }
        }
        ++it;
    }
}

} // namespace

QT_BEGIN_NAMESPACE

using namespace Qt3DCore;
using namespace Qt3DExtras;

namespace Qt3DRender {

Q_LOGGING_CATEGORY(GLTFExporterLog, "Qt3D.GLTFExport", QtWarningMsg)

const QString MATERIAL_DIFFUSE_COLOR = QStringLiteral("kd");
const QString MATERIAL_SPECULAR_COLOR = QStringLiteral("ks");
const QString MATERIAL_AMBIENT_COLOR = QStringLiteral("ka");

const QString MATERIAL_DIFFUSE_TEXTURE = QStringLiteral("diffuseTexture");
const QString MATERIAL_SPECULAR_TEXTURE = QStringLiteral("specularTexture");
const QString MATERIAL_NORMALS_TEXTURE = QStringLiteral("normalTexture");

const QString MATERIAL_SHININESS = QStringLiteral("shininess");
const QString MATERIAL_ALPHA = QStringLiteral("alpha");

// Custom extension for Qt3D
const QString MATERIAL_TEXTURE_SCALE = QStringLiteral("texCoordScale");

// Custom gooch material values
const QString MATERIAL_BETA = QStringLiteral("beta");
const QString MATERIAL_COOL_COLOR = QStringLiteral("kblue");
const QString MATERIAL_WARM_COLOR = QStringLiteral("kyellow");

const QString VERTICES_ATTRIBUTE_NAME = QAttribute::defaultPositionAttributeName();
const QString NORMAL_ATTRIBUTE_NAME =  QAttribute::defaultNormalAttributeName();
const QString TANGENT_ATTRIBUTE_NAME = QAttribute::defaultTangentAttributeName();
const QString TEXTCOORD_ATTRIBUTE_NAME = QAttribute::defaultTextureCoordinateAttributeName();
const QString COLOR_ATTRIBUTE_NAME = QAttribute::defaultColorAttributeName();

GLTFExporter::GLTFExporter() : QSceneExporter()
  , m_sceneRoot(nullptr)
  , m_rootNode(nullptr)
  , m_rootNodeEmpty(false)

{
}

GLTFExporter::~GLTFExporter()
{
}

/*!
    \class Qt3DRender::GLTFExporter
    \inmodule Qt3DRender
    \internal
    \brief Manages the export of a 3D scene to the GLTF format.

    Handles the export of a 3D scene to the GLTF format.
*/
// sceneRoot  : The root entity that contains the exported scene. If the sceneRoot doesn't have
//              any exportable components, it is not exported itself. This is because importing a
//              scene creates an empty top level entity to hold the scene.
// outDir     : The directory where the scene export directory is created in.
// exportName : Name of the directory created in outDir to hold the exported scene. Also used as
//              the file name base for generated files.
// options    : Export options.
//
// Supported options are:
// "compactJson" (bool): Removes unnecessary whitespace from the generated JSON file.

/*!
    Exports the scene to the GLTF format

    \a sceneRoot is the root entity that will be exported.
    If the sceneRoot does not have any exportable components, it is not exported itself.

    \a outDir is the directory in which the scene export is created.

    \a exportName is the name of the directory created in \c outDir that will hold
       the exported scene.

    \a options contain the export options.

    Returns true if the export was carried out successfully.
*/

bool GLTFExporter::exportScene(QEntity *sceneRoot, const QString &outDir,
                               const QString &exportName, const QVariantHash &options)
{
    m_bufferViewCount = 0;
    m_accessorCount = 0;
    m_meshCount = 0;
    m_materialCount = 0;
    m_techniqueCount = 0;
    m_textureCount = 0;
    m_imageCount = 0;
    m_shaderCount = 0;
    m_programCount = 0;
    m_nodeCount = 0;
    m_cameraCount = 0;
    m_lightCount = 0;
    m_renderPassCount = 0;
    m_effectCount = 0;

    m_gltfOpts.compactJson = options.value(QStringLiteral("compactJson"),
                                           QVariant(false)).toBool();

    QFileInfo outDirFileInfo(outDir);
    QString absoluteOutDir = outDirFileInfo.absoluteFilePath();
    if (!absoluteOutDir.endsWith(QLatin1Char('/')))
        absoluteOutDir.append(QLatin1Char('/'));
    m_exportName = exportName;
    m_sceneRoot = sceneRoot;
    QString finalExportDir = absoluteOutDir + m_exportName;
    if (!finalExportDir.endsWith(QLatin1Char('/')))
        finalExportDir.append(QLatin1Char('/'));

    QDir outDirDir(absoluteOutDir);

    // Make sure outDir exists
    if (outDirFileInfo.exists()) {
        if (!outDirFileInfo.isDir()) {
            qCWarning(GLTFExporterLog, "outDir is not a directory: '%ls'",
                      qUtf16PrintableImpl(absoluteOutDir));
            return false;
        }
    } else {
        if (!outDirDir.mkpath(outDirFileInfo.absoluteFilePath())) {
            qCWarning(GLTFExporterLog, "outDir could not be created: '%ls'",
                      qUtf16PrintableImpl(absoluteOutDir));
            return false;
        }
    }

    // Create temporary directory for exporting
    QTemporaryDir exportDir;

    if (!exportDir.isValid()) {
        qCWarning(GLTFExporterLog, "Temporary export directory could not be created");
        return false;
    }
    m_exportDir = exportDir.path();
    m_exportDir.append(QStringLiteral("/"));

    qCDebug(GLTFExporterLog, "Output directory: %ls", qUtf16PrintableImpl(absoluteOutDir));
    qCDebug(GLTFExporterLog, "Export name: %ls", qUtf16PrintableImpl(m_exportName));
    qCDebug(GLTFExporterLog, "Temp export dir: %ls", qUtf16PrintableImpl(m_exportDir));
    qCDebug(GLTFExporterLog, "Final export dir: %ls", qUtf16PrintableImpl(finalExportDir));

    parseScene();

    // Export scene to temporary directory
    if (!saveScene()) {
        qCWarning(GLTFExporterLog, "Exporting GLTF scene failed");
        return false;
    }

    // Create final export directory
    if (!outDirDir.mkpath(m_exportName)) {
        qCWarning(GLTFExporterLog, "Final export directory could not be created: '%ls'",
                  qUtf16PrintableImpl(finalExportDir));
        return false;
    }

    // As a safety feature, we don't indiscriminately delete existing directory or it's contents,
    // but instead look for an old export and delete only related files.
    clearOldExport(finalExportDir);

    // Files copied from resources will have read-only permissions, which isn't ideal in cases
    // where export is done on top of an existing export.
    // Since different file systems handle permissions differently, we grab the target permissions
    // from the qgltf file, which we created ourselves.
    QFile gltfFile(m_exportDir + m_exportName + QStringLiteral(".qgltf"));
    QFile::Permissions targetPermissions = gltfFile.permissions();

    // Copy exported scene to actual export directory
    for (const auto &sourceFileStr : qAsConst(m_exportedFiles)) {
        QFileInfo fiSource(m_exportDir + sourceFileStr);
        QFileInfo fiDestination(finalExportDir + sourceFileStr);
        if (fiDestination.exists()) {
            QFile(fiDestination.absoluteFilePath()).remove();
            qCDebug(GLTFExporterLog, "Removed old file: '%ls'",
                    qUtf16PrintableImpl(fiDestination.absoluteFilePath()));
        }
        QString srcPath = fiSource.absoluteFilePath();
        QString destPath = fiDestination.absoluteFilePath();
        if (!QFile(srcPath).copy(destPath)) {
            qCWarning(GLTFExporterLog, "  Failed to copy file: '%ls' -> '%ls'",
                      qUtf16PrintableImpl(srcPath), qUtf16PrintableImpl(destPath));
            // Don't fail entire export because file copy failed - if there is somehow a read-only
            // file with same name already in the export dir after cleanup we did, let's just assume
            // it's the same file we want rather than risk deleting unrelated protected file.
        } else {
            qCDebug(GLTFExporterLog, "  Copied file: '%ls' -> '%ls'",
                    qUtf16PrintableImpl(srcPath), qUtf16PrintableImpl(destPath));
            QFile(destPath).setPermissions(targetPermissions);
        }
    }

    // Clean up after export

    m_buffer.clear();
    m_meshMap.clear();
    m_materialMap.clear();
    m_cameraMap.clear();
    m_lightMap.clear();
    m_transformMap.clear();
    m_imageMap.clear();
    m_textureIdMap.clear();
    m_meshInfo.clear();
    m_materialInfo.clear();
    m_cameraInfo.clear();
    m_lightInfo.clear();
    m_exportedFiles.clear();
    m_renderPassIdMap.clear();
    m_shaderInfo.clear();
    m_programInfo.clear();
    m_techniqueIdMap.clear();
    m_effectIdMap.clear();
    qDeleteAll(m_defaultObjectCache);
    m_defaultObjectCache.clear();
    m_propertyCache.clear();

    delNode(m_rootNode);

    return true;
}

void GLTFExporter::cacheDefaultProperties(GLTFExporter::PropertyCacheType type)
{
    if (m_defaultObjectCache.contains(type))
        return;

    QObject *defaultObject = nullptr;

    switch (type) {
    case TypeConeMesh:
        defaultObject = new QConeMesh;
        break;
    case TypeCuboidMesh:
        defaultObject = new QCuboidMesh;
        break;
    case TypeCylinderMesh:
        defaultObject = new QCylinderMesh;
        break;
    case TypePlaneMesh:
        defaultObject = new QPlaneMesh;
        break;
    case TypeSphereMesh:
        defaultObject = new QSphereMesh;
        break;
    case TypeTorusMesh:
        defaultObject = new QTorusMesh;
        break;
    default:
        return; // Unsupported type
    }

    // Store the default object for property comparisons
    m_defaultObjectCache.insert(type, defaultObject);

    // Cache metaproperties of supported types (but not their parent class types)
    const QMetaObject *meta = defaultObject->metaObject();
    QVector<QMetaProperty> properties;
    properties.reserve(meta->propertyCount() - meta->propertyOffset());
    for (int i = meta->propertyOffset(); i < meta->propertyCount(); ++i) {
        if (meta->property(i).isWritable())
            properties.append(meta->property(i));
    }

    m_propertyCache.insert(type, properties);
}

// Copies textures from original locations to the temporary export directory.
// If texture names conflict, they are renamed.
void GLTFExporter::copyTextures()
{
    qCDebug(GLTFExporterLog, "Copying textures...");
    QHash<QString, QString> copiedMap;
    for (auto texIt = m_textureIdMap.constBegin(); texIt != m_textureIdMap.constEnd(); ++texIt) {
        QFileInfo fi(texIt.key());
        QString absoluteFilePath;
        if (texIt.key().startsWith(QStringLiteral(":")))
            absoluteFilePath = texIt.key();
        else
            absoluteFilePath = fi.absoluteFilePath();
        if (copiedMap.contains(absoluteFilePath)) {
            // Texture has already been copied
            qCDebug(GLTFExporterLog, "  Skipped copying duplicate texture: '%ls'",
                    qUtf16PrintableImpl(absoluteFilePath));
            if (!m_imageMap.contains(texIt.key()))
                m_imageMap.insert(texIt.key(), copiedMap.value(absoluteFilePath));
        } else {
            QString fileName = fi.fileName();
            QString outFile = m_exportDir;
            outFile.append(fileName);
            QFileInfo fiTry(outFile);
            if (fiTry.exists()) {
                static const QString outFileTemplate = QStringLiteral("%2_%3.%4");
                int counter = 0;
                QString tryFile = outFile;
                QString suffix = fiTry.suffix();
                QString base = fiTry.baseName();
                while (fiTry.exists()) {
                    fileName = outFileTemplate.arg(base).arg(counter++).arg(suffix);
                    tryFile = m_exportDir;
                    tryFile.append(fileName);
                    fiTry.setFile(tryFile);
                }
                outFile = tryFile;
            }
            if (!QFile(absoluteFilePath).copy(outFile)) {
                qCWarning(GLTFExporterLog, "  Failed to copy texture: '%ls' -> '%ls'",
                          qUtf16PrintableImpl(absoluteFilePath), qUtf16PrintableImpl(outFile));
            } else {
                qCDebug(GLTFExporterLog, "  Copied texture: '%ls' -> '%ls'",
                        qUtf16PrintableImpl(absoluteFilePath), qUtf16PrintableImpl(outFile));
            }
            // Generate actual target file (as current exportDir is temp dir)
            copiedMap.insert(absoluteFilePath, fileName);
            m_exportedFiles.insert(fileName);
            m_imageMap.insert(texIt.key(), fileName);
        }
    }
}

// Creates shaders to the temporary export directory.
void GLTFExporter::createShaders()
{
    qCDebug(GLTFExporterLog, "Creating shaders...");
    for (const auto &si : qAsConst(m_shaderInfo)) {
        const QString fileName = m_exportDir + si.uri;
        QFile f(fileName);
        if (f.open(QIODevice::WriteOnly | QIODevice::Text | QIODevice::Truncate)) {
            m_exportedFiles.insert(QFileInfo(f.fileName()).fileName());
            f.write(si.code);
            f.close();
        } else {
            qCWarning(GLTFExporterLog, "  Writing shaderfile '%ls' failed!",
                      qUtf16PrintableImpl(fileName));
        }
    }
}


void GLTFExporter::parseEntities(const QEntity *entity, Node *parentNode)
{
    if (entity) {
        Node *node =  new Node;
        node->name = entity->objectName();
        node->uniqueName = newNodeName();

        int irrelevantComponents = 0;
        const auto components = entity->components();
        for (auto component : components) {
            if (auto mesh = qobject_cast<QGeometryRenderer *>(component))
                m_meshMap.insert(node, mesh);
            else if (auto material = qobject_cast<QMaterial *>(component))
                m_materialMap.insert(node, material);
            else if (auto transform = qobject_cast<Qt3DCore::QTransform *>(component))
                m_transformMap.insert(node, transform);
            else if (auto camera = qobject_cast<QCameraLens *>(component))
                m_cameraMap.insert(node, camera);
            else if (auto light = qobject_cast<QAbstractLight *>(component))
                m_lightMap.insert(node, light);
            else
                irrelevantComponents++;
        }
        if (!parentNode) {
            m_rootNode = node;
            if (irrelevantComponents == entity->components().size())
                m_rootNodeEmpty = true;
        } else {
            parentNode->children.append(node);
        }
        qCDebug(GLTFExporterLog, "Parsed entity '%ls' -> '%ls'",
                qUtf16PrintableImpl(entity->objectName()), qUtf16PrintableImpl(node->uniqueName));

        for (auto child : entity->children())
            parseEntities(qobject_cast<QEntity *>(child), node);
    }
}

void GLTFExporter::parseScene()
{
    parseEntities(m_sceneRoot, nullptr);
    parseMaterials();
    parseMeshes();
    parseCameras();
    parseLights();
}

void GLTFExporter::parseMaterials()
{
    qCDebug(GLTFExporterLog, "Parsing materials...");

    int materialCount = 0;
    for (auto it = m_materialMap.constBegin(); it != m_materialMap.constEnd(); ++it) {
        QMaterial *material = it.value();

        MaterialInfo matInfo;
        matInfo.name = newMaterialName();
        matInfo.originalName = material->objectName();

        // Is material common or custom?
        if (qobject_cast<QPhongMaterial *>(material)) {
            matInfo.type = MaterialInfo::TypePhong;
        } else if (auto phongAlpha = qobject_cast<QPhongAlphaMaterial *>(material)) {
            matInfo.type = MaterialInfo::TypePhongAlpha;
            matInfo.blendArguments.resize(4);
            matInfo.blendEquations.resize(2);
            matInfo.blendArguments[0] = int(phongAlpha->sourceRgbArg());
            matInfo.blendArguments[1] = int(phongAlpha->sourceAlphaArg());
            matInfo.blendArguments[2] = int(phongAlpha->destinationRgbArg());
            matInfo.blendArguments[3] = int(phongAlpha->destinationAlphaArg());
            matInfo.blendEquations[0] = int(phongAlpha->blendFunctionArg());
            matInfo.blendEquations[1] = int(phongAlpha->blendFunctionArg());
        } else if (qobject_cast<QDiffuseMapMaterial *>(material)) {
            matInfo.type = MaterialInfo::TypeDiffuseMap;
        } else if (qobject_cast<QDiffuseSpecularMapMaterial *>(material)) {
            matInfo.type = MaterialInfo::TypeDiffuseSpecularMap;
        } else if (qobject_cast<QNormalDiffuseMapAlphaMaterial *>(material)) {
            matInfo.values.insert(QStringLiteral("transparent"), QVariant(true));
            matInfo.type = MaterialInfo::TypeNormalDiffuseMapAlpha;
        } else if (qobject_cast<QNormalDiffuseMapMaterial *>(material)) {
            matInfo.type = MaterialInfo::TypeNormalDiffuseMap;
        } else if (qobject_cast<QNormalDiffuseSpecularMapMaterial *>(material)) {
            matInfo.type = MaterialInfo::TypeNormalDiffuseSpecularMap;
        } else if (qobject_cast<QGoochMaterial *>(material)) {
            matInfo.type = MaterialInfo::TypeGooch;
        } else if (qobject_cast<QPerVertexColorMaterial *>(material)) {
            matInfo.type = MaterialInfo::TypePerVertex;
        } else {
            matInfo.type = MaterialInfo::TypeCustom;
        }

        if (matInfo.type == MaterialInfo::TypeCustom) {
            if (material->effect()) {
                if (!m_effectIdMap.contains(material->effect()))
                    m_effectIdMap.insert(material->effect(), newEffectName());
                parseTechniques(material);
            }
        } else {
            // Default materials do not have separate effect, all effect parameters are stored as
            // material values.
            if (material->effect()) {
                QVector<QParameter *> parameters = material->effect()->parameters();
                for (auto param : parameters) {
                    if (param->value().type() == QVariant::Color) {
                        QColor color = param->value().value<QColor>();
                        if (param->name() == MATERIAL_AMBIENT_COLOR) {
                            matInfo.colors.insert(QStringLiteral("ambient"), color);
                        } else if (param->name() == MATERIAL_DIFFUSE_COLOR) {
                            if (matInfo.type == MaterialInfo::TypePhongAlpha) {
                                matInfo.values.insert(QStringLiteral("transparency"), float(color.alphaF()));
                                color.setAlphaF(1.0f);
                            }
                            matInfo.colors.insert(QStringLiteral("diffuse"), color);
                        } else if (param->name() == MATERIAL_SPECULAR_COLOR) {
                            matInfo.colors.insert(QStringLiteral("specular"), color);
                        } else if (param->name() == MATERIAL_COOL_COLOR) { // Custom Qt3D gooch
                            matInfo.colors.insert(QStringLiteral("cool"), color);
                        } else if (param->name() == MATERIAL_WARM_COLOR) { // Custom Qt3D gooch
                            matInfo.colors.insert(QStringLiteral("warm"), color);
                        } else {
                            matInfo.colors.insert(param->name(), color);
                        }
                    } else if (param->value().canConvert<QAbstractTexture *>()) {
                        const QString urlString = textureVariantToUrl(param->value());
                        if (param->name() == MATERIAL_DIFFUSE_TEXTURE)
                            matInfo.textures.insert(QStringLiteral("diffuse"), urlString);
                        else if (param->name() == MATERIAL_SPECULAR_TEXTURE)
                            matInfo.textures.insert(QStringLiteral("specular"), urlString);
                        else if (param->name() == MATERIAL_NORMALS_TEXTURE)
                            matInfo.textures.insert(QStringLiteral("normal"), urlString);
                        else
                            matInfo.textures.insert(param->name(), urlString);
                    } else if (param->name() == MATERIAL_SHININESS) {
                        matInfo.values.insert(QStringLiteral("shininess"), param->value());
                    } else if (param->name() == MATERIAL_BETA) { // Custom Qt3D param for gooch
                        matInfo.values.insert(QStringLiteral("beta"), param->value());
                    } else if (param->name() == MATERIAL_ALPHA) {
                        if (matInfo.type == MaterialInfo::TypeGooch)
                            matInfo.values.insert(QStringLiteral("alpha"), param->value());
                        else
                            matInfo.values.insert(QStringLiteral("transparency"), param->value());
                    } else if (param->name() == MATERIAL_TEXTURE_SCALE) { // Custom Qt3D param
                        matInfo.values.insert(QStringLiteral("textureScale"), param->value());
                    } else {
                        qCDebug(GLTFExporterLog,
                                "Common material had unknown parameter: '%ls'",
                                qUtf16PrintableImpl(param->name()));
                    }
                }
            }
        }

        if (GLTFExporterLog().isDebugEnabled()) {
            qCDebug(GLTFExporterLog, "  Material #%i", materialCount);
            qCDebug(GLTFExporterLog, "    name: '%ls'", qUtf16PrintableImpl(matInfo.name));
            qCDebug(GLTFExporterLog, "    originalName: '%ls'",
                    qUtf16PrintableImpl(matInfo.originalName));
            qCDebug(GLTFExporterLog, "    type: %i", matInfo.type);
            qCDebug(GLTFExporterLog) << "    colors:" << matInfo.colors;
            qCDebug(GLTFExporterLog) << "    values:" << matInfo.values;
            qCDebug(GLTFExporterLog) << "    textures:" << matInfo.textures;
        }

        m_materialInfo.insert(material, matInfo);
        materialCount++;
    }
}

void GLTFExporter::parseMeshes()
{
    qCDebug(GLTFExporterLog, "Parsing meshes...");

    int meshCount = 0;
    for (auto it = m_meshMap.constBegin(); it != m_meshMap.constEnd(); ++it) {
        Node *node = it.key();
        QGeometryRenderer *mesh = it.value();

        MeshInfo meshInfo;
        meshInfo.originalName = mesh->objectName();
        meshInfo.name = newMeshName();
        meshInfo.materialName = m_materialInfo.value(m_materialMap.value(node)).name;

        if (qobject_cast<QConeMesh *>(mesh)) {
            meshInfo.meshType = TypeConeMesh;
            meshInfo.meshTypeStr = QStringLiteral("cone");
        } else if (qobject_cast<QCuboidMesh *>(mesh)) {
            meshInfo.meshType = TypeCuboidMesh;
            meshInfo.meshTypeStr = QStringLiteral("cuboid");
        } else if (qobject_cast<QCylinderMesh *>(mesh)) {
            meshInfo.meshType = TypeCylinderMesh;
            meshInfo.meshTypeStr = QStringLiteral("cylinder");
        } else if (qobject_cast<QPlaneMesh *>(mesh)) {
            meshInfo.meshType = TypePlaneMesh;
            meshInfo.meshTypeStr = QStringLiteral("plane");
        } else if (qobject_cast<QSphereMesh *>(mesh)) {
            meshInfo.meshType = TypeSphereMesh;
            meshInfo.meshTypeStr = QStringLiteral("sphere");
        } else if (qobject_cast<QTorusMesh *>(mesh)) {
            meshInfo.meshType = TypeTorusMesh;
            meshInfo.meshTypeStr = QStringLiteral("torus");
        } else {
            meshInfo.meshType = TypeNone;
        }

        if (meshInfo.meshType != TypeNone) {
            meshInfo.meshComponent = mesh;
            cacheDefaultProperties(meshInfo.meshType);

            if (GLTFExporterLog().isDebugEnabled()) {
                qCDebug(GLTFExporterLog, "  Mesh #%i: (%ls/%ls)", meshCount,
                        qUtf16PrintableImpl(meshInfo.name), qUtf16PrintableImpl(meshInfo.originalName));
                qCDebug(GLTFExporterLog, "    material: '%ls'",
                        qUtf16PrintableImpl(meshInfo.materialName));
                qCDebug(GLTFExporterLog, "    basic mesh type: '%s'",
                        mesh->metaObject()->className());
            }
        } else {
            meshInfo.meshComponent = nullptr;
            QGeometry *meshGeometry = mesh->geometry();

            if (!meshGeometry) {
                qCWarning(GLTFExporterLog, "Ignoring mesh without geometry!");
                continue;
            }

            QAttribute *indexAttrib = nullptr;
            const quint16 *indexPtr = nullptr;

            struct VertexAttrib {
                QAttribute *att;
                const float *ptr;
                QString usage;
                uint offset;
                uint stride;
                int index;
            };

            QVector<VertexAttrib> vAttribs;
            vAttribs.reserve(meshGeometry->attributes().size());

            uint stride(0);

            const auto attributes = meshGeometry->attributes();
            for (QAttribute *att : attributes) {
                if (att->attributeType() == QAttribute::IndexAttribute) {
                    indexAttrib = att;
                    indexPtr = reinterpret_cast<const quint16 *>(att->buffer()->data().constData());
                } else {
                    VertexAttrib vAtt;
                    vAtt.att = att;
                    vAtt.ptr = reinterpret_cast<const float *>(att->buffer()->data().constData());
                    if (att->name() == VERTICES_ATTRIBUTE_NAME)
                        vAtt.usage = QStringLiteral("POSITION");
                    else if (att->name() == NORMAL_ATTRIBUTE_NAME)
                        vAtt.usage = QStringLiteral("NORMAL");
                    else if (att->name() == TEXTCOORD_ATTRIBUTE_NAME)
                        vAtt.usage = QStringLiteral("TEXCOORD_0");
                    else if (att->name() == COLOR_ATTRIBUTE_NAME)
                        vAtt.usage = QStringLiteral("COLOR");
                    else if (att->name() == TANGENT_ATTRIBUTE_NAME)
                        vAtt.usage = QStringLiteral("TANGENT");
                    else
                        vAtt.usage = att->name();

                    vAtt.offset = att->byteOffset() / sizeof(float);
                    vAtt.index = vAtt.offset;
                    vAtt.stride = att->byteStride() > 0
                            ? att->byteStride() / sizeof(float) - att->vertexSize() : 0;
                    stride += att->vertexSize();

                    vAttribs << vAtt;
                }
            }

            int attribCount(vAttribs.size());
            if (!attribCount) {
                qCWarning(GLTFExporterLog, "Ignoring mesh without any attributes!");
                continue;
            }

            QByteArray vertexBuf;
            const int vertexCount = vAttribs.at(0).att->count();
            vertexBuf.resize(stride * vertexCount * sizeof(float));
            float *p = reinterpret_cast<float *>(vertexBuf.data());

            // Create interleaved buffer
            for (int i = 0; i < vertexCount; ++i) {
                for (int j = 0; j < attribCount; ++j) {
                    VertexAttrib &vAtt = vAttribs[j];
                    for (uint k = 0; k < vAtt.att->vertexSize(); ++k)
                        *p++ = vAtt.ptr[vAtt.index++];
                    vAtt.index += vAtt.stride;
                }
            }

            MeshInfo::BufferView vertexBufView;
            vertexBufView.name = newBufferViewName();
            vertexBufView.length = vertexBuf.size();
            vertexBufView.offset = m_buffer.size();
            vertexBufView.componentType = GL_FLOAT;
            vertexBufView.target = GL_ARRAY_BUFFER;
            meshInfo.views.append(vertexBufView);

            QByteArray indexBuf;
            MeshInfo::BufferView indexBufView;
            uint indexCount = 0;
            if (indexAttrib) {
                const uint indexSize = indexAttrib->vertexBaseType() == QAttribute::UnsignedShort
                        ? sizeof(quint16) : sizeof(quint32);
                indexCount = indexAttrib->count();
                uint srcIndex = indexAttrib->byteOffset() / indexSize;
                const uint indexStride = indexAttrib->byteStride()
                        ? indexAttrib->byteStride() / indexSize - 1: 0;
                indexBuf.resize(indexCount * indexSize);
                if (indexSize == sizeof(quint32)) {
                    quint32 *dst = reinterpret_cast<quint32 *>(indexBuf.data());
                    const quint32 *src = reinterpret_cast<const quint32 *>(indexPtr);
                    for (uint j = 0; j < indexCount; ++j) {
                        *dst++ = src[srcIndex++];
                        srcIndex += indexStride;
                    }
                } else {
                    quint16 *dst = reinterpret_cast<quint16 *>(indexBuf.data());
                    for (uint j = 0; j < indexCount; ++j) {
                        *dst++ = indexPtr[srcIndex++];
                        srcIndex += indexStride;
                    }
                }

                indexBufView.name = newBufferViewName();
                indexBufView.length = indexBuf.size();
                indexBufView.offset = vertexBufView.offset + vertexBufView.length;
                indexBufView.componentType = indexSize == sizeof(quint32)
                        ? GL_UNSIGNED_INT : GL_UNSIGNED_SHORT;
                indexBufView.target = GL_ELEMENT_ARRAY_BUFFER;
                meshInfo.views.append(indexBufView);
            }

            MeshInfo::Accessor acc;
            uint startOffset = 0;

            acc.bufferView = vertexBufView.name;
            acc.stride = stride * sizeof(float);
            acc.count = vertexCount;
            acc.componentType = vertexBufView.componentType;
            for (int i = 0; i < attribCount; ++i) {
                const VertexAttrib &vAtt = vAttribs.at(i);
                acc.name = newAccessorName();
                acc.usage = vAtt.usage;
                acc.offset = startOffset * sizeof(float);
                switch (vAtt.att->vertexSize()) {
                case 1:
                    acc.type = QStringLiteral("SCALAR");
                    break;
                case 2:
                    acc.type = QStringLiteral("VEC2");
                    break;
                case 3:
                    acc.type = QStringLiteral("VEC3");
                    break;
                case 4:
                    acc.type = QStringLiteral("VEC4");
                    break;
                case 9:
                    acc.type = QStringLiteral("MAT3");
                    break;
                case 16:
                    acc.type = QStringLiteral("MAT4");
                    break;
                default:
                    qCWarning(GLTFExporterLog, "Invalid vertex size: %d", vAtt.att->vertexSize());
                    break;
                }
                meshInfo.accessors.append(acc);
                startOffset += vAtt.att->vertexSize();
            }

            // Index
            if (indexAttrib) {
                acc.name = newAccessorName();
                acc.usage = QStringLiteral("INDEX");
                acc.bufferView = indexBufView.name;
                acc.offset = 0;
                acc.stride = 0;
                acc.count = indexCount;
                acc.componentType = indexBufView.componentType;
                acc.type = QStringLiteral("SCALAR");
                meshInfo.accessors.append(acc);
            }
            m_buffer.append(vertexBuf);
            m_buffer.append(indexBuf);

            if (GLTFExporterLog().isDebugEnabled()) {
                qCDebug(GLTFExporterLog, "  Mesh #%i: (%ls/%ls)", meshCount,
                        qUtf16PrintableImpl(meshInfo.name), qUtf16PrintableImpl(meshInfo.originalName));
                qCDebug(GLTFExporterLog, "    Vertex count: %i", vertexCount);
                qCDebug(GLTFExporterLog, "    Bytes per vertex: %i", stride);
                qCDebug(GLTFExporterLog, "    Vertex buffer size (bytes): %i", vertexBuf.size());
                qCDebug(GLTFExporterLog, "    Index buffer size (bytes): %i", indexBuf.size());
                QStringList sl;
                const auto views = meshInfo.views;
                for (const auto &bv : views)
                    sl << bv.name;
                qCDebug(GLTFExporterLog) << "    buffer views:" << sl;
                sl.clear();
                for (const auto &acc : qAsConst(meshInfo.accessors))
                    sl << acc.name;
                qCDebug(GLTFExporterLog) << "    accessors:" << sl;
                qCDebug(GLTFExporterLog, "    material: '%ls'",
                        qUtf16PrintableImpl(meshInfo.materialName));
            }
        }

        meshCount++;
        m_meshInfo.insert(mesh, meshInfo);
    }

    qCDebug(GLTFExporterLog, "Total buffer size: %i", m_buffer.size());
}

void GLTFExporter::parseCameras()
{
    qCDebug(GLTFExporterLog, "Parsing cameras...");
    int cameraCount = 0;

    for (auto it = m_cameraMap.constBegin(); it != m_cameraMap.constEnd(); ++it) {
        QCameraLens *camera = it.value();
        CameraInfo c;

        if (camera->projectionType() == QCameraLens::PerspectiveProjection) {
            c.perspective = true;
            c.aspectRatio = camera->aspectRatio();
            c.yfov = qDegreesToRadians(camera->fieldOfView());
        } else {
            c.perspective = false;
            // Note that accurate conversion from four properties of QCameraLens to just two
            // properties of gltf orthographic cameras is not feasible. Only centered cases
            // convert properly.
            c.xmag = qAbs(camera->left() - camera->right());
            c.ymag = qAbs(camera->top() - camera->bottom());
        }

        c.originalName = camera->objectName();
        c.name = newCameraName();
        c.znear = camera->nearPlane();
        c.zfar = camera->farPlane();

        // GLTF cameras point in -Z by default, the rest is in the
        // node matrix, so no separate look-at params given here, unless it's actually QCamera.
        QCamera *cameraEntity = nullptr;
        const QVector<QEntity *> entities = camera->entities();
        if (entities.size() == 1)
            cameraEntity = qobject_cast<QCamera *>(entities.at(0));
        c.cameraEntity = cameraEntity;

        m_cameraInfo.insert(camera, c);
        if (GLTFExporterLog().isDebugEnabled()) {
            qCDebug(GLTFExporterLog, "  Camera: #%i: (%ls/%ls)", cameraCount++,
                    qUtf16PrintableImpl(c.name), qUtf16PrintableImpl(c.originalName));
            qCDebug(GLTFExporterLog, "    Aspect ratio: %f", c.aspectRatio);
            qCDebug(GLTFExporterLog, "    Fov: %f", c.yfov);
            qCDebug(GLTFExporterLog, "    Near: %f", c.znear);
            qCDebug(GLTFExporterLog, "    Far: %f", c.zfar);
        }
    }
}

void GLTFExporter::parseLights()
{
    qCDebug(GLTFExporterLog, "Parsing lights...");
    int lightCount = 0;
    for (auto it = m_lightMap.constBegin(); it != m_lightMap.constEnd(); ++it) {
        QAbstractLight *light = it.value();
        LightInfo lightInfo;
        lightInfo.direction = QVector3D();
        lightInfo.attenuation = QVector3D();
        lightInfo.cutOffAngle = 0.0f;
        lightInfo.type = light->type();
        if (light->type() == QAbstractLight::SpotLight) {
            QSpotLight *spot = qobject_cast<QSpotLight *>(light);
            lightInfo.direction = spot->localDirection();
            lightInfo.attenuation = QVector3D(spot->constantAttenuation(),
                                              spot->linearAttenuation(),
                                              spot->quadraticAttenuation());
            lightInfo.cutOffAngle = spot->cutOffAngle();
        } else if (light->type() == QAbstractLight::PointLight) {
            QPointLight *point = qobject_cast<QPointLight *>(light);
            lightInfo.attenuation = QVector3D(point->constantAttenuation(),
                                              point->linearAttenuation(),
                                              point->quadraticAttenuation());
        } else if (light->type() == QAbstractLight::DirectionalLight) {
            QDirectionalLight *directional = qobject_cast<QDirectionalLight *>(light);
            lightInfo.direction = directional->worldDirection();
        }
        lightInfo.color = light->color();
        lightInfo.intensity = light->intensity();

        lightInfo.originalName = light->objectName();
        lightInfo.name = newLightName();

        m_lightInfo.insert(light, lightInfo);

        if (GLTFExporterLog().isDebugEnabled()) {
            qCDebug(GLTFExporterLog, "  Light #%i: (%ls/%ls)", lightCount++,
                    qUtf16PrintableImpl(lightInfo.name), qUtf16PrintableImpl(lightInfo.originalName));
            qCDebug(GLTFExporterLog, "    Type: %i", lightInfo.type);
            qCDebug(GLTFExporterLog, "    Color: (%i, %i, %i, %i)", lightInfo.color.red(),
                    lightInfo.color.green(), lightInfo.color.blue(), lightInfo.color.alpha());
            qCDebug(GLTFExporterLog, "    Intensity: %f", lightInfo.intensity);
            qCDebug(GLTFExporterLog, "    Direction: (%f, %f, %f)", lightInfo.direction.x(),
                    lightInfo.direction.y(), lightInfo.direction.z());
            qCDebug(GLTFExporterLog, "    Attenuation: (%f, %f, %f)", lightInfo.attenuation.x(),
                    lightInfo.attenuation.y(), lightInfo.attenuation.z());
            qCDebug(GLTFExporterLog, "    CutOffAngle: %f", lightInfo.cutOffAngle);
        }
    }
}

void GLTFExporter::parseTechniques(QMaterial *material)
{
    int techniqueCount = 0;
    qCDebug(GLTFExporterLog, "  Parsing material techniques...");

    const auto techniques = material->effect()->techniques();
    for (auto technique : techniques) {
        QString techName;
        if (m_techniqueIdMap.contains(technique)) {
            techName = m_techniqueIdMap.value(technique);
        } else {
            techName = newTechniqueName();
            parseRenderPasses(technique);

        }
        m_techniqueIdMap.insert(technique, techName);

        techniqueCount++;

        if (GLTFExporterLog().isDebugEnabled()) {
            qCDebug(GLTFExporterLog, "    Technique #%i", techniqueCount);
            qCDebug(GLTFExporterLog, "      name: '%ls'", qUtf16PrintableImpl(techName));
        }
    }
}

void GLTFExporter::parseRenderPasses(QTechnique *technique)
{
    int passCount = 0;
    qCDebug(GLTFExporterLog, "    Parsing render passes for technique...");

    const auto renderPasses = technique->renderPasses();
    for (auto pass : renderPasses) {
        QString name;
        if (m_renderPassIdMap.contains(pass)) {
            name = m_renderPassIdMap.value(pass);
        } else {
            name = newRenderPassName();
            m_renderPassIdMap.insert(pass, name);
            if (pass->shaderProgram() && !m_programInfo.contains(pass->shaderProgram())) {
                ProgramInfo pi;
                pi.name = newProgramName();
                pi.vertexShader = addShaderInfo(QShaderProgram::Vertex,
                                                pass->shaderProgram()->vertexShaderCode());
                pi.tessellationControlShader =
                        addShaderInfo(QShaderProgram::Fragment,
                                      pass->shaderProgram()->tessellationControlShaderCode());
                pi.tessellationEvaluationShader =
                        addShaderInfo(QShaderProgram::TessellationControl,
                                      pass->shaderProgram()->tessellationEvaluationShaderCode());
                pi.geometryShader = addShaderInfo(QShaderProgram::TessellationEvaluation,
                                                  pass->shaderProgram()->geometryShaderCode());
                pi.fragmentShader = addShaderInfo(QShaderProgram::Geometry,
                                                  pass->shaderProgram()->fragmentShaderCode());
                pi.computeShader = addShaderInfo(QShaderProgram::Compute,
                                                 pass->shaderProgram()->computeShaderCode());
                m_programInfo.insert(pass->shaderProgram(), pi);
                qCDebug(GLTFExporterLog, "      program: '%ls'", qUtf16PrintableImpl(pi.name));
            }
        }
        passCount++;

        if (GLTFExporterLog().isDebugEnabled()) {
            qCDebug(GLTFExporterLog, "      Render pass #%i", passCount);
            qCDebug(GLTFExporterLog, "        name: '%ls'", qUtf16PrintableImpl(name));
        }
    }
}

QString GLTFExporter::addShaderInfo(QShaderProgram::ShaderType type, QByteArray code)
{
    if (code.isEmpty())
        return QString();

    for (const auto &si : qAsConst(m_shaderInfo)) {
        if (si.type == QShaderProgram::Vertex && code == si.code)
            return si.name;
    }

    ShaderInfo newInfo;
    newInfo.type = type;
    newInfo.code = code;
    newInfo.name = newShaderName();
    newInfo.uri = newInfo.name + QStringLiteral(".glsl");

    m_shaderInfo.append(newInfo);

    qCDebug(GLTFExporterLog, "      shader: '%ls'", qUtf16PrintableImpl(newInfo.name));

    return newInfo.name;
}

bool GLTFExporter::saveScene()
{
    qCDebug(GLTFExporterLog, "Saving scene...");

    QVector<MeshInfo::BufferView> bvList;
    QVector<MeshInfo::Accessor> accList;
    for (auto it = m_meshInfo.begin(); it != m_meshInfo.end(); ++it) {
        auto &mi = it.value();
        for (auto &v : mi.views)
            bvList << v;
        for (auto &acc : mi.accessors)
            accList << acc;
    }

    m_obj = QJsonObject();

    QJsonObject asset;
    asset["generator"] = QString(QStringLiteral("GLTFExporter %1")).arg(qVersion());
    asset["version"] = QStringLiteral("1.0");
    asset["premultipliedAlpha"] = true;
    m_obj["asset"] = asset;

    QString bufName = m_exportName + QStringLiteral(".bin");
    QString binFileName = m_exportDir + bufName;
    QFile f(binFileName);
    QFileInfo fiBin(binFileName);

    if (f.open(QIODevice::WriteOnly | QIODevice::Truncate)) {
        qCDebug(GLTFExporterLog, "  Writing '%ls'", qUtf16PrintableImpl(binFileName));
        m_exportedFiles.insert(fiBin.fileName());
        f.write(m_buffer);
        f.close();
    } else {
        qCWarning(GLTFExporterLog, "  Creating buffers file '%ls' failed!",
                  qUtf16PrintableImpl(binFileName));
        return false;
    }

    QJsonObject buffers;
    QJsonObject buffer;
    buffer["byteLength"] = m_buffer.size();
    buffer["type"] = QStringLiteral("arraybuffer");
    buffer["uri"] = bufName;
    buffers["buf"] = buffer;
    m_obj["buffers"] = buffers;

    QJsonObject bufferViews;
    for (const auto &bv : qAsConst(bvList)) {
        QJsonObject bufferView;
        bufferView["buffer"] = QStringLiteral("buf");
        bufferView["byteLength"] = int(bv.length);
        bufferView["byteOffset"] = int(bv.offset);
        if (bv.target)
            bufferView["target"] = int(bv.target);
        bufferViews[bv.name] = bufferView;
    }
    if (bufferViews.size())
        m_obj["bufferViews"] = bufferViews;

    QJsonObject accessors;
    for (const auto &acc : qAsConst(accList)) {
        QJsonObject accessor;
        accessor["bufferView"] = acc.bufferView;
        accessor["byteOffset"] = int(acc.offset);
        accessor["byteStride"] = int(acc.stride);
        accessor["count"] = int(acc.count);
        accessor["componentType"] = int(acc.componentType);
        accessor["type"] = acc.type;
        accessors[acc.name] = accessor;
    }
    if (accessors.size())
        m_obj["accessors"] = accessors;

    QJsonObject meshes;
    for (auto it = m_meshInfo.begin(); it != m_meshInfo.end(); ++it) {
        auto &meshInfo = it.value();
        QJsonObject mesh;
        mesh["name"] = meshInfo.originalName;
        if (meshInfo.meshType != TypeNone) {
            QJsonObject properties;
            exportGenericProperties(properties, meshInfo.meshType, meshInfo.meshComponent);
            mesh["type"] = meshInfo.meshTypeStr;
            mesh["properties"] = properties;
            mesh["material"] = meshInfo.materialName;
        } else {
            QJsonArray prims;
            QJsonObject prim;
            prim["mode"] = 4; // triangles
            QJsonObject attrs;
            const auto meshAccessors = meshInfo.accessors;
            for (const auto &acc : meshAccessors) {
                if (acc.usage != QStringLiteral("INDEX"))
                    attrs[acc.usage] = acc.name;
                else
                    prim["indices"] = acc.name;
            }
            prim["attributes"] = attrs;
            prim["material"] = meshInfo.materialName;
            prims.append(prim);
            mesh["primitives"] = prims;
        }
        meshes[meshInfo.name] = mesh;
    }
    if (meshes.size())
        m_obj["meshes"] = meshes;

    QJsonObject cameras;
    for (const auto &camInfo : qAsConst(m_cameraInfo)) {
        QJsonObject camera;
        QJsonObject proj;
        proj["znear"] = camInfo.znear;
        proj["zfar"] = camInfo.zfar;
        if (camInfo.perspective) {
            proj["aspect_ratio"] = camInfo.aspectRatio;
            proj["yfov"] = camInfo.yfov;
            camera["type"] = QStringLiteral("perspective");
            camera["perspective"] = proj;
        } else {
            proj["xmag"] = camInfo.xmag;
            proj["ymag"] = camInfo.ymag;
            camera["type"] = QStringLiteral("orthographic");
            camera["orthographic"] = proj;
        }
        if (camInfo.cameraEntity) {
            camera["position"] = vec2jsvec(camInfo.cameraEntity->position());
            camera["upVector"] = vec2jsvec(camInfo.cameraEntity->upVector());
            camera["viewCenter"] = vec2jsvec(camInfo.cameraEntity->viewCenter());
        }
        camera["name"] = camInfo.originalName;
        cameras[camInfo.name] = camera;
    }
    if (cameras.size())
        m_obj["cameras"] = cameras;

    QJsonArray sceneNodes;
    QJsonObject nodes;
    if (m_rootNodeEmpty) {
        // Don't export the root node if it is there just to group the scene, so we don't get
        // an extra empty node when we import the scene back.
        for (auto c : qAsConst(m_rootNode->children))
            sceneNodes << exportNodes(c, nodes);
    } else {
        sceneNodes << exportNodes(m_rootNode, nodes);
    }
    m_obj["nodes"] = nodes;

    QJsonObject scenes;
    QJsonObject defaultScene;
    defaultScene["nodes"] = sceneNodes;
    scenes["defaultScene"] = defaultScene;
    m_obj["scenes"] = scenes;
    m_obj["scene"] = QStringLiteral("defaultScene");

    QJsonObject materials;

    exportMaterials(materials);
    if (materials.size())
        m_obj["materials"] = materials;

    // Lights must be declared as extensions to the top-level glTF object
    QJsonObject lights;
    for (auto it = m_lightInfo.begin(); it != m_lightInfo.end(); ++it) {
        const auto &lightInfo = it.value();
        QJsonObject light;
        QJsonObject lightDetails;
        QString type;
        if (lightInfo.type == QAbstractLight::SpotLight) {
            type = QStringLiteral("spot");
            lightDetails["falloffAngle"] = lightInfo.cutOffAngle;
        } else if (lightInfo.type == QAbstractLight::PointLight) {
            type = QStringLiteral("point");
        } else if (lightInfo.type == QAbstractLight::DirectionalLight) {
            type = QStringLiteral("directional");
        }
        light["type"] = type;
        if (lightInfo.type == QAbstractLight::SpotLight
                || lightInfo.type == QAbstractLight::DirectionalLight) {
            // The GLTF specs are bit unclear whether there is a direction parameter
            // for spot/directional lights, or are they supposed to just use the
            // parent transforms for direction, but we do need it in any case, so we add it.
            lightDetails["direction"] = vec2jsvec(lightInfo.direction);

        }
        if (lightInfo.type == QAbstractLight::SpotLight
                || lightInfo.type == QAbstractLight::PointLight) {
            lightDetails["constantAttenuation"] = lightInfo.attenuation.x();
            lightDetails["linearAttenuation"] = lightInfo.attenuation.y();
            lightDetails["quadraticAttenuation"] = lightInfo.attenuation.z();
        }
        lightDetails["color"] = col2jsvec(lightInfo.color, false);
        lightDetails["intensity"] = lightInfo.intensity; // Not in spec but needed
        light["name"] = lightInfo.originalName; // Not in spec but we want to pass the name anyway
        light[type] = lightDetails;
        lights[lightInfo.name] = light;
    }
    if (lights.size()) {
        QJsonObject extensions;
        QJsonObject common;
        common["lights"] = lights;
        extensions["KHR_materials_common"] = common;
        m_obj["extensions"] = extensions;
    }

    // Save effects for custom materials
    // Note that we are not saving effects, techniques, render passes, shader programs, or shaders
    // strictly according to GLTF format, but rather in our expanded QGLTF custom format,
    // since the GLTF format doesn't quite match our needs.
    // Having our own format also vastly simplifies export and import of custom materials,
    // since we are not trying to push a round peg into a square hole.
    // If use cases arise in future where our exported GLTF scenes need to be loaded by third party
    // GLTF loaders, we could add an export option to do so, but the exported scene would never
    // be quite the same as the original.
    QJsonObject effects;
    for (auto it = m_effectIdMap.constBegin(); it != m_effectIdMap.constEnd(); ++it) {
        QEffect *effect = it.key();
        const QString effectName = it.value();
        QJsonObject effectObj;
        QJsonObject paramObj;

        const auto effectParameters = effect->parameters();
        for (QParameter *param : effectParameters)
            exportParameter(paramObj, param->name(), param->value());
        if (!effect->objectName().isEmpty())
            effectObj["name"] = effect->objectName();
        if (!paramObj.isEmpty())
            effectObj["parameters"] = paramObj;
        QJsonArray techs;
        const auto effectTechniques = effect->techniques();
        for (auto tech : effectTechniques)
            techs << m_techniqueIdMap.value(tech);
        effectObj["techniques"] = techs;
        effects[effectName] = effectObj;
    }
    if (effects.size())
        m_obj["effects"] = effects;

    // Save techniques for custom materials.
    QJsonObject techniques;
    for (auto it = m_techniqueIdMap.constBegin(); it != m_techniqueIdMap.constEnd(); ++it) {
        QTechnique *technique = it.key();

        QJsonObject techObj;
        QJsonObject filterKeyObj;
        QJsonObject paramObj;
        QJsonArray renderPassArr;

        const auto techniqueFilterKeys = technique->filterKeys();
        for (QFilterKey *filterKey : techniqueFilterKeys)
            setVarToJSonObject(filterKeyObj, filterKey->name(), filterKey->value());

        const auto techniqueRenderPasses = technique->renderPasses();
        for (QRenderPass *pass : techniqueRenderPasses)
            renderPassArr << m_renderPassIdMap.value(pass);

        const auto techniqueParameters = technique->parameters();
        for (QParameter *param : techniqueParameters)
            exportParameter(paramObj, param->name(), param->value());

        const QGraphicsApiFilter *gFilter = technique->graphicsApiFilter();
        if (gFilter) {
            QJsonObject graphicsApiFilterObj;
            graphicsApiFilterObj["api"] = gFilter->api();
            graphicsApiFilterObj["profile"] = gFilter->profile();
            graphicsApiFilterObj["minorVersion"] = gFilter->minorVersion();
            graphicsApiFilterObj["majorVersion"] = gFilter->majorVersion();
            if (!gFilter->vendor().isEmpty())
                graphicsApiFilterObj["vendor"] = gFilter->vendor();
            QJsonArray extensions;
            for (const auto &extName : gFilter->extensions())
                extensions << extName;
            if (!extensions.isEmpty())
                graphicsApiFilterObj["extensions"] = extensions;
            techObj["gapifilter"] = graphicsApiFilterObj;
        }
        if (!technique->objectName().isEmpty())
            techObj["name"] = technique->objectName();
        if (!filterKeyObj.isEmpty())
            techObj["filterkeys"] = filterKeyObj;
        if (!paramObj.isEmpty())
            techObj["parameters"] = paramObj;
        if (!renderPassArr.isEmpty())
            techObj["renderpasses"] = renderPassArr;
        techniques[it.value()] = techObj;
    }
    if (techniques.size())
        m_obj["techniques"] = techniques;

    // Save render passes for custom materials.
    QJsonObject passes;
    for (auto it = m_renderPassIdMap.constBegin(); it != m_renderPassIdMap.constEnd(); ++it) {
        const QRenderPass *pass = it.key();
        const QString passId = it.value();

        QJsonObject passObj;
        QJsonObject filterKeyObj;
        QJsonObject paramObj;
        QJsonObject stateObj;

        for (QFilterKey *filterKey : pass->filterKeys())
            setVarToJSonObject(filterKeyObj, filterKey->name(), filterKey->value());
        for (QParameter *param : pass->parameters())
            exportParameter(paramObj, param->name(), param->value());
        exportRenderStates(stateObj, pass);

        if (!pass->objectName().isEmpty())
            passObj["name"] = pass->objectName();
        if (!filterKeyObj.isEmpty())
            passObj["filterkeys"] = filterKeyObj;
        if (!paramObj.isEmpty())
            passObj["parameters"] = paramObj;
        if (!stateObj.isEmpty())
            passObj["states"] = stateObj;
        passObj["program"] = m_programInfo.value(pass->shaderProgram()).name;
        passes[passId] = passObj;

    }
    if (passes.size())
        m_obj["renderpasses"] = passes;

    // Save programs for custom materials
    QJsonObject programs;
    for (auto it = m_programInfo.constBegin(); it != m_programInfo.constEnd(); ++it) {
        const QShaderProgram *program = it.key();
        const ProgramInfo pi = it.value();

        QJsonObject progObj;
        if (!program->objectName().isEmpty())
            progObj["name"] = program->objectName();
        progObj["vertexShader"] = pi.vertexShader;
        progObj["fragmentShader"] = pi.fragmentShader;
        // Qt3D additions
        if (!pi.tessellationControlShader.isEmpty())
            progObj["tessCtrlShader"] = pi.tessellationControlShader;
        if (!pi.tessellationEvaluationShader.isEmpty())
            progObj["tessEvalShader"] = pi.tessellationEvaluationShader;
        if (!pi.geometryShader.isEmpty())
            progObj["geometryShader"] = pi.geometryShader;
        if (!pi.computeShader.isEmpty())
            progObj["computeShader"] = pi.computeShader;
        programs[pi.name] = progObj;

    }
    if (programs.size())
        m_obj["programs"] = programs;

    // Save shaders for custom materials
    QJsonObject shaders;
    for (const auto &si : qAsConst(m_shaderInfo)) {
        QJsonObject shaderObj;
        shaderObj["uri"] = si.uri;
        shaders[si.name] = shaderObj;

    }
    if (shaders.size())
        m_obj["shaders"] = shaders;

    // Copy textures and shaders into temporary directory
    copyTextures();
    createShaders();

    QJsonObject textures;
    QHash<QString, QString> imageKeyMap; // uri -> key
    for (auto it = m_textureIdMap.constBegin(); it != m_textureIdMap.constEnd(); ++it) {
        QJsonObject texture;
        if (!imageKeyMap.contains(it.key()))
            imageKeyMap[it.key()] = newImageName();
        texture["source"] = imageKeyMap[it.key()];
        texture["format"] = GL_RGBA;
        texture["internalFormat"] = GL_RGBA;
        texture["sampler"] = QStringLiteral("sampler_mip_rep");
        texture["target"] = GL_TEXTURE_2D;
        texture["type"] = GL_UNSIGNED_BYTE;
        textures[it.value()] = texture;
    }
    if (textures.size()) {
        m_obj["textures"] = textures;
        QJsonObject samplers;
        QJsonObject sampler;
        sampler["magFilter"] = GL_LINEAR;
        sampler["minFilter"] = GL_LINEAR_MIPMAP_LINEAR;
        sampler["wrapS"] = GL_REPEAT;
        sampler["wrapT"] = GL_REPEAT;
        samplers["sampler_mip_rep"] = sampler;
        m_obj["samplers"] = samplers;
    }

    QJsonObject images;
    for (auto it = imageKeyMap.constBegin(); it != imageKeyMap.constEnd(); ++it) {
        QJsonObject image;
        image["uri"] = m_imageMap.value(it.key());
        images[it.value()] = image;
    }
    if (images.size())
        m_obj["images"] = images;

    m_doc.setObject(m_obj);

    QString gltfName = m_exportDir + m_exportName + QStringLiteral(".qgltf");
    f.setFileName(gltfName);
    qCDebug(GLTFExporterLog, "  Writing JSON file: '%ls'", qUtf16PrintableImpl(gltfName));

    if (f.open(QIODevice::WriteOnly | QIODevice::Text | QIODevice::Truncate)) {
        m_exportedFiles.insert(QFileInfo(f.fileName()).fileName());
        QByteArray json = m_doc.toJson(m_gltfOpts.compactJson ? QJsonDocument::Compact
                                                              : QJsonDocument::Indented);
        f.write(json);
        f.close();
    } else {
        qCWarning(GLTFExporterLog, "  Writing JSON file '%ls' failed!",
                  qUtf16PrintableImpl(gltfName));
        return false;
    }

    QString qrcName = m_exportDir + m_exportName + QStringLiteral(".qrc");
    f.setFileName(qrcName);
    qCDebug(GLTFExporterLog, "Writing '%ls'", qUtf16PrintableImpl(qrcName));
    if (f.open(QIODevice::WriteOnly | QIODevice::Text | QIODevice::Truncate)) {
        QByteArray pre = "<RCC><qresource prefix=\"/gltf_res\">\n";
        QByteArray post = "</qresource></RCC>\n";
        f.write(pre);
        for (const auto &file : qAsConst(m_exportedFiles)) {
            QString line = QString(QStringLiteral("  <file>%1</file>\n")).arg(file);
            f.write(line.toUtf8());
        }
        f.write(post);
        f.close();
        m_exportedFiles.insert(QFileInfo(f.fileName()).fileName());
    } else {
        qCWarning(GLTFExporterLog, "  Creating qrc file '%ls' failed!",
                  qUtf16PrintableImpl(qrcName));
        return false;
    }

    qCDebug(GLTFExporterLog, "Saving done!");

    return true;
}

void GLTFExporter::delNode(GLTFExporter::Node *n)
{
    if (!n)
        return;
    for (auto *c : qAsConst(n->children))
        delNode(c);
    delete n;
}

QString GLTFExporter::exportNodes(GLTFExporter::Node *n, QJsonObject &nodes)
{
    QJsonObject node;
    node["name"] = n->name;
    QJsonArray children;
    for (auto c : qAsConst(n->children))
        children << exportNodes(c, nodes);
    node["children"] = children;
    if (auto transform = m_transformMap.value(n))
        node["matrix"] = matrix2jsvec(transform->matrix());

    if (auto mesh = m_meshMap.value(n)) {
        QJsonArray meshList;
        meshList.append(m_meshInfo.value(mesh).name);
        node["meshes"] = meshList;
    }

    if (auto camera = m_cameraMap.value(n))
        node["camera"] = m_cameraInfo.value(camera).name;

    if (auto light = m_lightMap.value(n)) {
        QJsonObject extensions;
        QJsonObject lights;
        lights["light"] = m_lightInfo.value(light).name;
        extensions["KHR_materials_common"] = lights;
        node["extensions"] = extensions;
    }

    nodes[n->uniqueName] = node;
    return n->uniqueName;
}

void GLTFExporter::exportMaterials(QJsonObject &materials)
{
    QHash<QString, bool> imageHasAlpha;

    for (auto matIt = m_materialInfo.constBegin(); matIt != m_materialInfo.constEnd(); ++matIt) {
        const QMaterial *material = matIt.key();
        const MaterialInfo &matInfo = matIt.value();

        QJsonObject materialObj;
        materialObj["name"] = matInfo.originalName;

        if (matInfo.type == MaterialInfo::TypeCustom) {
            QVector<QParameter *> parameters = material->parameters();
            QJsonObject paramObj;
            for (auto param : parameters)
                exportParameter(paramObj, param->name(), param->value());
            materialObj["effect"] = m_effectIdMap.value(material->effect());
            materialObj["parameters"] = paramObj;
        } else {
            bool opaque = true;
            QJsonObject vals;
            for (auto it = matInfo.textures.constBegin(); it != matInfo.textures.constEnd(); ++it) {
                QString key = it.key();
                if (key == QStringLiteral("normal")) // avoid clashing with the vertex normals
                    key = QStringLiteral("normalmap");
                // Alpha is supported for diffuse textures, but have to check the image data to
                // decide if blending is needed
                if (key == QStringLiteral("diffuse")) {
                    QString imgFn = it.value();
                    if (imageHasAlpha.contains(imgFn)) {
                        if (imageHasAlpha[imgFn])
                            opaque = false;
                    } else {
                        QImage img(imgFn);
                        if (!img.isNull()) {
                            if (img.hasAlphaChannel()) {
                                for (int y = 0; opaque && y < img.height(); ++y) {
                                    for (int x = 0; opaque && x < img.width(); ++x) {
                                        if (qAlpha(img.pixel(x, y)) < 255)
                                            opaque = false;
                                    }
                                }
                            }
                            imageHasAlpha[imgFn] = !opaque;
                        } else {
                            qCWarning(GLTFExporterLog,
                                      "Cannot determine presence of alpha for '%ls'",
                                      qUtf16PrintableImpl(imgFn));
                        }
                    }
                }
                vals[key] = m_textureIdMap.value(it.value());
            }
            for (auto it = matInfo.values.constBegin(); it != matInfo.values.constEnd(); ++it) {
                if (vals.contains(it.key()))
                    continue;
                setVarToJSonObject(vals, it.key(), it.value());
            }
            for (auto it = matInfo.colors.constBegin(); it != matInfo.colors.constEnd(); ++it) {
                if (vals.contains(it.key()))
                    continue;
                // Alpha is supported for the diffuse color. < 1 will enable blending.
                const bool alpha = (it.key() == QStringLiteral("diffuse"))
                        && (matInfo.type != MaterialInfo::TypeCustom);
                if (alpha && it.value().alphaF() < 1.0f)
                    opaque = false;
                vals[it.key()] = col2jsvec(it.value(), alpha);
            }
            // Material is a common material, so export it as such.
            QJsonObject commonMat;
            if (matInfo.type == MaterialInfo::TypeGooch)
                commonMat["technique"] = QStringLiteral("GOOCH"); // Qt3D specific extension
            else if (matInfo.type == MaterialInfo::TypePerVertex)
                commonMat["technique"] = QStringLiteral("PERVERTEX"); // Qt3D specific extension
            else
                commonMat["technique"] = QStringLiteral("PHONG");

            // Set the values as-is. "normalmap" is our own extension, not in the spec.
            // However, RGB colors have to be promoted to RGBA since the spec uses
            // vec4, and all types are pre-defined for common material values.
            promoteColorsToRGBA(&vals);
            if (!vals.isEmpty())
                commonMat["values"] = vals;

            // Blend function handling is our own extension used for Phong Alpha material.
            QJsonObject functions;
            if (!matInfo.blendEquations.isEmpty())
                functions["blendEquationSeparate"] = vec2jsvec(matInfo.blendEquations);
            if (!matInfo.blendArguments.isEmpty())
                functions["blendFuncSeparate"] = vec2jsvec(matInfo.blendArguments);
            if (!functions.isEmpty())
                commonMat["functions"] = functions;
            QJsonObject extensions;
            extensions["KHR_materials_common"] = commonMat;
            materialObj["extensions"] = extensions;
        }

        materials[matInfo.name] = materialObj;
    }
}

void GLTFExporter::exportGenericProperties(QJsonObject &jsonObj, PropertyCacheType type,
                                           QObject *obj)
{
    QVector<QMetaProperty> properties = m_propertyCache.value(type);
    QObject *defaultObject = m_defaultObjectCache.value(type);
    for (const QMetaProperty &property : properties) {
        // Only output property if it is different from default
        QVariant defaultValue = defaultObject->property(property.name());
        QVariant objectValue = obj->property(property.name());
        if (defaultValue != objectValue)
            setVarToJSonObject(jsonObj, QString::fromLatin1(property.name()), objectValue);
    }
}

void GLTFExporter::clearOldExport(const QString &dir)
{
    // Look for .qrc file with same name
    QRegularExpression re(QStringLiteral("<file>(.*)</file>"));
    QFile qrcFile(dir + m_exportName + QStringLiteral(".qrc"));
    if (qrcFile.open(QIODevice::ReadOnly | QIODevice::Text)) {
        while (!qrcFile.atEnd()) {
            QByteArray line = qrcFile.readLine();
            QRegularExpressionMatch match = re.match(line);
            if (match.hasMatch()) {
                QString fileName = match.captured(1);
                QString filePathName = dir + fileName;
                QFile::remove(filePathName);
                qCDebug(GLTFExporterLog, "Removed old file: '%ls'",
                        qUtf16PrintableImpl(filePathName));
            }
        }
        qrcFile.close();
        qrcFile.remove();
        qCDebug(GLTFExporterLog, "Removed old file: '%ls'",
                qUtf16PrintableImpl(qrcFile.fileName()));
    }
}

void GLTFExporter::exportParameter(QJsonObject &jsonObj, const QString &name,
                                   const QVariant &variant)
{
    QLatin1String typeStr("type");
    QLatin1String valueStr("value");

    QJsonObject paramObj;

    if (variant.canConvert<QAbstractTexture *>()) {
        paramObj[typeStr] = GL_SAMPLER_2D;
        paramObj[valueStr] = m_textureIdMap.value(textureVariantToUrl(variant));
    } else {
        switch (QMetaType::Type(variant.type())) {
        case QMetaType::Bool:
            paramObj[typeStr] = GL_BOOL;
            paramObj[valueStr] = variant.toBool();
            break;
        case QMetaType::Int: // fall through
        case QMetaType::Long: // fall through
        case QMetaType::LongLong:
            paramObj[typeStr] = GL_INT;
            paramObj[valueStr] = variant.toInt();
            break;
        case QMetaType::UInt: // fall through
        case QMetaType::ULong: // fall through
        case QMetaType::ULongLong:
            paramObj[typeStr] = GL_UNSIGNED_INT;
            paramObj[valueStr] = variant.toInt();
            break;
        case QMetaType::Short:
            paramObj[typeStr] = GL_SHORT;
            paramObj[valueStr] = variant.toInt();
            break;
        case QMetaType::UShort:
            paramObj[typeStr] = GL_UNSIGNED_SHORT;
            paramObj[valueStr] = variant.toInt();
            break;
        case QMetaType::Char:
            paramObj[typeStr] = GL_BYTE;
            paramObj[valueStr] = variant.toInt();
            break;
        case QMetaType::UChar:
            paramObj[typeStr] = GL_UNSIGNED_BYTE;
            paramObj[valueStr] = variant.toInt();
            break;
        case QMetaType::QColor:
            paramObj[typeStr] = GL_FLOAT_VEC4;
            paramObj[valueStr] = col2jsvec(variant.value<QColor>(), true);
            break;
        case QMetaType::Float:
            paramObj[typeStr] = GL_FLOAT;
            paramObj[valueStr] = variant.value<float>();
            break;
        case QMetaType::QVector2D:
            paramObj[typeStr] = GL_FLOAT_VEC2;
            paramObj[valueStr] = vec2jsvec(variant.value<QVector2D>());
            break;
        case QMetaType::QVector3D:
            paramObj[typeStr] = GL_FLOAT_VEC3;
            paramObj[valueStr] = vec2jsvec(variant.value<QVector3D>());
            break;
        case QMetaType::QVector4D:
            paramObj[typeStr] = GL_FLOAT_VEC4;
            paramObj[valueStr] = vec2jsvec(variant.value<QVector4D>());
            break;
        case QMetaType::QMatrix4x4:
            paramObj[typeStr] = GL_FLOAT_MAT4;
            paramObj[valueStr] = matrix2jsvec(variant.value<QMatrix4x4>());
            break;
        default:
            qCWarning(GLTFExporterLog, "Unknown value type for '%ls'", qUtf16PrintableImpl(name));
            break;
        }
    }

    jsonObj[name] = paramObj;
}

void GLTFExporter::exportRenderStates(QJsonObject &jsonObj, const QRenderPass *pass)
{
    QJsonArray enableStates;
    QJsonObject funcObj;
    const auto renderStates = pass->renderStates();
    for (QRenderState *state : renderStates) {
        QJsonArray arr;
        if (qobject_cast<QAlphaCoverage *>(state)) {
            enableStates << GL_SAMPLE_ALPHA_TO_COVERAGE;
        } else if (qobject_cast<QAlphaTest *>(state)) {
            auto s = qobject_cast<QAlphaTest *>(state);
            arr << s->alphaFunction();
            arr << s->referenceValue();
            funcObj["alphaTest"] = arr;
        } else if (qobject_cast<QBlendEquation *>(state)) {
            auto s = qobject_cast<QBlendEquation *>(state);
            arr << s->blendFunction();
            funcObj["blendEquationSeparate"] = arr;
        } else if (qobject_cast<QBlendEquationArguments *>(state)) {
            auto s = qobject_cast<QBlendEquationArguments *>(state);
            arr << s->sourceRgb();
            arr << s->sourceAlpha();
            arr << s->destinationRgb();
            arr << s->destinationAlpha();
            arr << s->bufferIndex();
            funcObj["blendFuncSeparate"] = arr;
        } else if (qobject_cast<QClipPlane *>(state)) {
            auto s = qobject_cast<QClipPlane *>(state);
            arr << s->planeIndex();
            arr << s->normal().x();
            arr << s->normal().y();
            arr << s->normal().z();
            arr << s->distance();
            funcObj["clipPlane"] = arr;
        } else if (qobject_cast<QColorMask *>(state)) {
            auto s = qobject_cast<QColorMask *>(state);
            arr << s->isRedMasked();
            arr << s->isGreenMasked();
            arr << s->isBlueMasked();
            arr << s->isAlphaMasked();
            funcObj["colorMask"] = arr;
        } else if (qobject_cast<QCullFace *>(state)) {
            auto s = qobject_cast<QCullFace *>(state);
            arr << s->mode();
            funcObj["cullFace"] = arr;
        } else if (qobject_cast<QDepthRange *>(state)) {
            auto s = qobject_cast<QDepthRange *>(state);
            arr << s->nearValue();
            arr << s->farValue();
            funcObj["depthRange"] = arr;
        } else if (qobject_cast<QDepthTest *>(state)) {
            auto s = qobject_cast<QDepthTest *>(state);
            arr << s->depthFunction();
            funcObj["depthFunc"] = arr;
        } else if (qobject_cast<QDithering *>(state)) {
            enableStates << GL_DITHER;
        } else if (qobject_cast<QFrontFace *>(state)) {
            auto s = qobject_cast<QFrontFace *>(state);
            arr << s->direction();
            funcObj["frontFace"] = arr;
        } else if (qobject_cast<QFrontFace *>(state)) {
            auto s = qobject_cast<QFrontFace *>(state);
            arr << s->direction();
            funcObj["frontFace"] = arr;
        } else if (qobject_cast<QMultiSampleAntiAliasing *>(state)) {
            enableStates << 0x809D; // GL_MULTISAMPLE
        } else if (qobject_cast<QNoDepthMask *>(state)) {
            arr << false;
            funcObj["depthMask"] = arr;
        } else if (qobject_cast<QPointSize *>(state)) {
            auto s = qobject_cast<QPointSize *>(state);
            arr << s->sizeMode();
            arr << s->value();
            funcObj["pointSize"] = arr;
        } else if (qobject_cast<QPolygonOffset *>(state)) {
            auto s = qobject_cast<QPolygonOffset *>(state);
            arr << s->scaleFactor();
            arr << s->depthSteps();
            funcObj["polygonOffset"] = arr;
        } else if (qobject_cast<QScissorTest *>(state)) {
            auto s = qobject_cast<QScissorTest *>(state);
            arr << s->left();
            arr << s->bottom();
            arr << s->width();
            arr << s->height();
            funcObj["scissor"] = arr;
        } else if (qobject_cast<QSeamlessCubemap *>(state)) {
            enableStates << 0x884F; // GL_TEXTURE_CUBE_MAP_SEAMLESS
        } else if (qobject_cast<QStencilMask *>(state)) {
            auto s = qobject_cast<QStencilMask *>(state);
            arr << int(s->frontOutputMask());
            arr << int(s->backOutputMask());
            funcObj["stencilMask"] = arr;
        } else if (qobject_cast<QStencilOperation *>(state)) {
            auto s = qobject_cast<QStencilOperation *>(state);
            arr << s->front()->stencilTestFailureOperation();
            arr << s->front()->depthTestFailureOperation();
            arr << s->front()->allTestsPassOperation();
            arr << s->back()->stencilTestFailureOperation();
            arr << s->back()->depthTestFailureOperation();
            arr << s->back()->allTestsPassOperation();
            funcObj["stencilOperation"] = arr;
        } else if (qobject_cast<QStencilTest *>(state)) {
            auto s = qobject_cast<QStencilTest *>(state);
            arr << int(s->front()->comparisonMask());
            arr << s->front()->referenceValue();
            arr << s->front()->stencilFunction();
            arr << int(s->back()->comparisonMask());
            arr << s->back()->referenceValue();
            arr << s->back()->stencilFunction();
            funcObj["stencilTest"] = arr;
        }
    }
    if (!enableStates.isEmpty())
        jsonObj["enable"] = enableStates;
    if (!funcObj.isEmpty())
        jsonObj["functions"] = funcObj;
}

QString GLTFExporter::newBufferViewName()
{
    return QString(QStringLiteral("bufferView_%1")).arg(++m_bufferViewCount);
}

QString GLTFExporter::newAccessorName()
{
    return QString(QStringLiteral("accessor_%1")).arg(++m_accessorCount);
}

QString GLTFExporter::newMeshName()
{
    return QString(QStringLiteral("mesh_%1")).arg(++m_meshCount);
}

QString GLTFExporter::newMaterialName()
{
    return QString(QStringLiteral("material_%1")).arg(++m_materialCount);
}

QString GLTFExporter::newTechniqueName()
{
    return QString(QStringLiteral("technique_%1")).arg(++m_techniqueCount);
}

QString GLTFExporter::newTextureName()
{
    return QString(QStringLiteral("texture_%1")).arg(++m_textureCount);
}

QString GLTFExporter::newImageName()
{
    return QString(QStringLiteral("image_%1")).arg(++m_imageCount);
}

QString GLTFExporter::newShaderName()
{
    return QString(QStringLiteral("shader_%1")).arg(++m_shaderCount);
}

QString GLTFExporter::newProgramName()
{
    return QString(QStringLiteral("program_%1")).arg(++m_programCount);
}

QString GLTFExporter::newNodeName()
{
    return QString(QStringLiteral("node_%1")).arg(++m_nodeCount);
}

QString GLTFExporter::newCameraName()
{
    return QString(QStringLiteral("camera_%1")).arg(++m_cameraCount);
}

QString GLTFExporter::newLightName()
{
    return QString(QStringLiteral("light_%1")).arg(++m_lightCount);
}

QString GLTFExporter::newRenderPassName()
{
    return QString(QStringLiteral("renderpass_%1")).arg(++m_renderPassCount);
}

QString GLTFExporter::newEffectName()
{
    return QString(QStringLiteral("effect_%1")).arg(++m_effectCount);
}

QString GLTFExporter::textureVariantToUrl(const QVariant &var)
{
    QString urlString;
    QAbstractTexture *texture = var.value<QAbstractTexture *>();
    if (texture->textureImages().size()) {
        QTextureImage *image = qobject_cast<QTextureImage *>(texture->textureImages().at(0));
        if (image) {
            urlString = QUrlHelper::urlToLocalFileOrQrc(image->source());
            if (!m_textureIdMap.contains(urlString))
                m_textureIdMap.insert(urlString, newTextureName());
        }
    }
    return urlString;
}

void GLTFExporter::setVarToJSonObject(QJsonObject &jsObj, const QString &key, const QVariant &var)
{
    switch (QMetaType::Type(var.type())) {
    case QMetaType::Bool:
        jsObj[key] = var.toBool();
        break;
    case QMetaType::Int:
        jsObj[key] = var.toInt();
        break;
    case QMetaType::Float:
        jsObj[key] = var.value<float>();
        break;
    case QMetaType::QSize:
        jsObj[key] = size2jsvec(var.toSize());
        break;
    case QMetaType::QVector2D:
        jsObj[key] = vec2jsvec(var.value<QVector2D>());
        break;
    case QMetaType::QVector3D:
        jsObj[key] = vec2jsvec(var.value<QVector3D>());
        break;
    case QMetaType::QVector4D:
        jsObj[key] = vec2jsvec(var.value<QVector4D>());
        break;
    case QMetaType::QMatrix4x4:
        jsObj[key] = matrix2jsvec(var.value<QMatrix4x4>());
        break;
    case QMetaType::QString:
        jsObj[key] = var.toString();
        break;
    case QMetaType::QColor:
        jsObj[key] = col2jsvec(var.value<QColor>(), true);
        break;
    default:
        qCWarning(GLTFExporterLog, "Unknown value type for '%ls'", qUtf16PrintableImpl(key));
        break;
    }
}

} // namespace Qt3DRender

QT_END_NAMESPACE

#include "moc_gltfexporter.cpp"