Added GLTF geometry loader

Based on scene parser.

Change-Id: I9e4a84926fffaf9e2fa69ac351cfa151b3e79e95
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

10 files changed, 1006 insertions, 0 deletions

diff --git a/src/plugins/geometryloaders/geometryloaders.pro b/src/plugins/geometryloaders/geometryloaders.pro
index 6f4b913cb..85ab48d01 100644
--- a/src/plugins/geometryloaders/geometryloaders.pro
+++ b/src/plugins/geometryloaders/geometryloaders.pro
@@ -1,2 +1,3 @@
 TEMPLATE = subdirs
 SUBDIRS += default
+SUBDIRS += gltf
diff --git a/src/plugins/geometryloaders/gltf/gltf.json b/src/plugins/geometryloaders/gltf/gltf.json
new file mode 100644
index 000000000..9ad97ce1a
--- /dev/null
+++ b/src/plugins/geometryloaders/gltf/gltf.json
@@ -0,0 +1,3 @@
+{
+    "Keys": ["gltf", "json", "qgltf"]
+}
diff --git a/src/plugins/geometryloaders/gltf/gltf.pro b/src/plugins/geometryloaders/gltf/gltf.pro
new file mode 100644
index 000000000..da805fae1
--- /dev/null
+++ b/src/plugins/geometryloaders/gltf/gltf.pro
@@ -0,0 +1,19 @@
+TARGET = gltfgeometryloader
+QT += core-private 3dcore 3dcore-private 3drender 3drender-private
+
+# Qt3D is free of Q_FOREACH - make sure it stays that way:
+DEFINES += QT_NO_FOREACH
+
+HEADERS += \
+    gltfgeometryloader.h \
+
+SOURCES += \
+    main.cpp \
+    gltfgeometryloader.cpp \
+
+DISTFILES += \
+    gltf.json
+
+PLUGIN_TYPE = geometryloaders
+PLUGIN_CLASS_NAME = GLTFGeometryLoaderPlugin
+load(qt_plugin)
diff --git a/src/plugins/geometryloaders/gltf/gltfgeometryloader.cpp b/src/plugins/geometryloaders/gltf/gltfgeometryloader.cpp
new file mode 100644
index 000000000..bc64ae41b
--- /dev/null
+++ b/src/plugins/geometryloaders/gltf/gltfgeometryloader.cpp
@@ -0,0 +1,439 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 Klaralvdalens Datakonsult AB (KDAB).
+** 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 "gltfgeometryloader.h"
+
+#include <QtCore/QDir>
+#include <QtCore/QJsonArray>
+#include <QtCore/QJsonObject>
+
+#include <QtGui/QOpenGLTexture>
+
+#include <Qt3DRender/QGeometry>
+#include <Qt3DRender/private/renderlogging_p.h>
+
+QT_BEGIN_NAMESPACE
+
+#ifndef qUtf16PrintableImpl // -Impl is a Qt 5.8 feature
+#  define qUtf16PrintableImpl(string) \
+    static_cast<const wchar_t*>(static_cast<const void*>(string.utf16()))
+#endif
+
+namespace Qt3DRender {
+
+Q_LOGGING_CATEGORY(GLTFGeometryLoaderLog, "Qt3D.GLTFGeometryLoader")
+
+#define KEY_ACCESSORS    QLatin1String("accessors")
+#define KEY_ATTRIBUTES   QLatin1String("attributes")
+#define KEY_BUFFER       QLatin1String("buffer")
+#define KEY_BUFFERS      QLatin1String("buffers")
+#define KEY_BYTE_LENGTH  QLatin1String("byteLength")
+#define KEY_BYTE_OFFSET  QLatin1String("byteOffset")
+#define KEY_BYTE_STRIDE  QLatin1String("byteStride")
+#define KEY_COUNT        QLatin1String("count")
+#define KEY_INDICES      QLatin1String("indices")
+#define KEY_MATERIAL     QLatin1String("material")
+#define KEY_MESHES       QLatin1String("meshes")
+#define KEY_NAME         QLatin1String("name")
+#define KEY_PRIMITIVES   QLatin1String("primitives")
+#define KEY_TARGET       QLatin1String("target")
+#define KEY_TYPE         QLatin1String("type")
+#define KEY_URI          QLatin1String("uri")
+
+#define KEY_BUFFER_VIEW         QLatin1String("bufferView")
+#define KEY_BUFFER_VIEWS        QLatin1String("bufferViews")
+#define KEY_COMPONENT_TYPE      QLatin1String("componentType")
+
+GLTFGeometryLoader::GLTFGeometryLoader()
+    : m_geometry(nullptr)
+{
+}
+
+GLTFGeometryLoader::~GLTFGeometryLoader()
+{
+    cleanup();
+}
+
+QGeometry *GLTFGeometryLoader::geometry() const
+{
+    return m_geometry;
+}
+
+bool GLTFGeometryLoader::load(QIODevice *ioDev, const QString &subMesh)
+{
+    Q_UNUSED(subMesh);
+
+    QByteArray jsonData = ioDev->readAll();
+    QJsonDocument sceneDocument = QJsonDocument::fromBinaryData(jsonData);
+    if (sceneDocument.isNull())
+        sceneDocument = QJsonDocument::fromJson(jsonData);
+
+    if (Q_UNLIKELY(!setJSON(sceneDocument))) {
+        qCWarning(GLTFGeometryLoaderLog, "not a JSON document");
+        return false;
+    }
+
+    auto file = qobject_cast<QFile*>(ioDev);
+    if (file) {
+        QFileInfo finfo(file->fileName());
+        setBasePath(finfo.dir().absolutePath());
+    }
+
+    m_mesh = subMesh;
+
+    parse();
+
+    return true;
+}
+
+GLTFGeometryLoader::BufferData::BufferData()
+    : length(0)
+    , data(nullptr)
+{
+}
+
+GLTFGeometryLoader::BufferData::BufferData(const QJsonObject &json)
+    : length(json.value(KEY_BYTE_LENGTH).toInt())
+    , path(json.value(KEY_URI).toString())
+    , data(nullptr)
+{
+}
+
+GLTFGeometryLoader::AccessorData::AccessorData()
+    : type(QAttribute::Float)
+    , dataSize(0)
+    , count(0)
+    , offset(0)
+    , stride(0)
+{
+
+}
+
+GLTFGeometryLoader::AccessorData::AccessorData(const QJsonObject &json)
+    : bufferViewName(json.value(KEY_BUFFER_VIEW).toString())
+    , type(accessorTypeFromJSON(json.value(KEY_COMPONENT_TYPE).toInt()))
+    , dataSize(accessorDataSizeFromJson(json.value(KEY_TYPE).toString()))
+    , count(json.value(KEY_COUNT).toInt())
+    , offset(0)
+    , stride(0)
+{
+    const auto byteOffset = json.value(KEY_BYTE_OFFSET);
+    if (!byteOffset.isUndefined())
+        offset = byteOffset.toInt();
+    const auto byteStride = json.value(KEY_BYTE_STRIDE);
+    if (!byteStride.isUndefined())
+        stride = byteStride.toInt();
+}
+
+void GLTFGeometryLoader::setBasePath(const QString &path)
+{
+    m_basePath = path;
+}
+
+bool GLTFGeometryLoader::setJSON(const QJsonDocument &json )
+{
+    if (!json.isObject()) {
+        return false;
+    }
+
+    m_json = json;
+
+    cleanup();
+
+    return true;
+}
+
+QString GLTFGeometryLoader::standardAttributeNameFromSemantic(const QString &semantic)
+{
+    //Standard Attributes
+    if (semantic.startsWith(QLatin1String("POSITION")))
+        return QAttribute::defaultPositionAttributeName();
+    if (semantic.startsWith(QLatin1String("NORMAL")))
+        return QAttribute::defaultNormalAttributeName();
+    if (semantic.startsWith(QLatin1String("TEXCOORD")))
+        return QAttribute::defaultTextureCoordinateAttributeName();
+    if (semantic.startsWith(QLatin1String("COLOR")))
+        return QAttribute::defaultColorAttributeName();
+    if (semantic.startsWith(QLatin1String("TANGENT")))
+        return QAttribute::defaultTangentAttributeName();
+
+    return QString();
+}
+
+void GLTFGeometryLoader::parse()
+{
+    const QJsonObject buffers = m_json.object().value(KEY_BUFFERS).toObject();
+    for (auto it = buffers.begin(), end = buffers.end(); it != end; ++it)
+        processJSONBuffer(it.key(), it.value().toObject());
+
+    const QJsonObject views = m_json.object().value(KEY_BUFFER_VIEWS).toObject();
+    loadBufferData();
+    for (auto it = views.begin(), end = views.end(); it != end; ++it)
+        processJSONBufferView(it.key(), it.value().toObject());
+    unloadBufferData();
+
+    const QJsonObject attrs = m_json.object().value(KEY_ACCESSORS).toObject();
+    for (auto it = attrs.begin(), end = attrs.end(); it != end; ++it)
+        processJSONAccessor(it.key(), it.value().toObject());
+
+    const QJsonObject meshes = m_json.object().value(KEY_MESHES).toObject();
+    for (auto it = meshes.begin(), end = meshes.end(); it != end && !m_geometry; ++it) {
+        const QJsonObject &mesh = it.value().toObject();
+        if (m_mesh.isEmpty() ||
+            m_mesh.compare(mesh.value(KEY_NAME).toString(), Qt::CaseInsensitive) == 0)
+            processJSONMesh(it.key(), mesh);
+    }
+}
+
+void GLTFGeometryLoader::cleanup()
+{
+    m_geometry = nullptr;
+    m_accessorDict.clear();
+    m_buffers.clear();
+}
+
+void GLTFGeometryLoader::processJSONBuffer(const QString &id, const QJsonObject &json)
+{
+    // simply cache buffers for lookup by buffer-views
+    m_bufferDatas[id] = BufferData(json);
+}
+
+void GLTFGeometryLoader::processJSONBufferView(const QString &id, const QJsonObject &json)
+{
+    QString bufName = json.value(KEY_BUFFER).toString();
+    const auto it = qAsConst(m_bufferDatas).find(bufName);
+    if (Q_UNLIKELY(it == m_bufferDatas.cend())) {
+        qCWarning(GLTFGeometryLoaderLog, "unknown buffer: %ls processing view: %ls",
+                  qUtf16PrintableImpl(bufName), qUtf16PrintableImpl(id));
+        return;
+    }
+    const auto &bufferData = *it;
+
+    int target = json.value(KEY_TARGET).toInt();
+    Qt3DRender::QBuffer::BufferType ty(Qt3DRender::QBuffer::VertexBuffer);
+
+    switch (target) {
+    case GL_ARRAY_BUFFER:           ty = Qt3DRender::QBuffer::VertexBuffer; break;
+    case GL_ELEMENT_ARRAY_BUFFER:   ty = Qt3DRender::QBuffer::IndexBuffer; break;
+    default:
+        qCWarning(GLTFGeometryLoaderLog, "buffer %ls unsupported target: %d",
+                  qUtf16PrintableImpl(id), target);
+        return;
+    }
+
+    quint64 offset = 0;
+    const auto byteOffset = json.value(KEY_BYTE_OFFSET);
+    if (!byteOffset.isUndefined()) {
+        offset = byteOffset.toInt();
+        qCDebug(GLTFGeometryLoaderLog, "bv: %ls has offset: %lld", qUtf16PrintableImpl(id), offset);
+    }
+
+    quint64 len = json.value(KEY_BYTE_LENGTH).toInt();
+
+    QByteArray bytes = bufferData.data->mid(offset, len);
+    if (Q_UNLIKELY(bytes.count() != int(len))) {
+        qCWarning(GLTFGeometryLoaderLog, "failed to read sufficient bytes from: %ls for view %ls",
+                  qUtf16PrintableImpl(bufferData.path), qUtf16PrintableImpl(id));
+    }
+
+    Qt3DRender::QBuffer *b(new Qt3DRender::QBuffer(ty));
+    b->setData(bytes);
+    m_buffers[id] = b;
+}
+
+void GLTFGeometryLoader::processJSONAccessor(const QString &id, const QJsonObject &json)
+{
+    m_accessorDict[id] = AccessorData(json);
+}
+
+void GLTFGeometryLoader::processJSONMesh(const QString &id, const QJsonObject &json)
+{
+    const QJsonArray primitivesArray = json.value(KEY_PRIMITIVES).toArray();
+    for (const QJsonValue &primitiveValue : primitivesArray) {
+        QJsonObject primitiveObject = primitiveValue.toObject();
+        QString material = primitiveObject.value(KEY_MATERIAL).toString();
+
+        if (Q_UNLIKELY(material.isEmpty())) {
+            qCWarning(GLTFGeometryLoaderLog, "malformed primitive on %ls, missing material value %ls",
+                      qUtf16PrintableImpl(id), qUtf16PrintableImpl(material));
+            continue;
+        }
+
+        QGeometry *meshGeometry = new QGeometry;
+
+        const QJsonObject attrs = primitiveObject.value(KEY_ATTRIBUTES).toObject();
+        for (auto it = attrs.begin(), end = attrs.end(); it != end; ++it) {
+            QString k = it.value().toString();
+            const auto accessorIt = qAsConst(m_accessorDict).find(k);
+            if (Q_UNLIKELY(accessorIt == m_accessorDict.cend())) {
+                qCWarning(GLTFGeometryLoaderLog, "unknown attribute accessor: %ls on mesh %ls",
+                          qUtf16PrintableImpl(k), qUtf16PrintableImpl(id));
+                continue;
+            }
+
+            const QString attrName = it.key();
+            QString attributeName = standardAttributeNameFromSemantic(attrName);
+            if (attributeName.isEmpty())
+                attributeName = attrName;
+
+            //Get buffer handle for accessor
+            Qt3DRender::QBuffer *buffer = m_buffers.value(accessorIt->bufferViewName, nullptr);
+            if (Q_UNLIKELY(!buffer)) {
+                qCWarning(GLTFGeometryLoaderLog, "unknown buffer-view: %ls processing accessor: %ls",
+                          qUtf16PrintableImpl(accessorIt->bufferViewName), qUtf16PrintableImpl(id));
+                continue;
+            }
+
+            QAttribute *attribute = new QAttribute(buffer,
+                                                   attributeName,
+                                                   accessorIt->type,
+                                                   accessorIt->dataSize,
+                                                   accessorIt->count,
+                                                   accessorIt->offset,
+                                                   accessorIt->stride);
+            attribute->setAttributeType(QAttribute::VertexAttribute);
+            meshGeometry->addAttribute(attribute);
+        }
+
+        const auto indices = primitiveObject.value(KEY_INDICES);
+        if (!indices.isUndefined()) {
+            QString k = indices.toString();
+            const auto accessorIt = qAsConst(m_accessorDict).find(k);
+            if (Q_UNLIKELY(accessorIt == m_accessorDict.cend())) {
+                qCWarning(GLTFGeometryLoaderLog, "unknown index accessor: %ls on mesh %ls",
+                          qUtf16PrintableImpl(k), qUtf16PrintableImpl(id));
+            } else {
+                //Get buffer handle for accessor
+                Qt3DRender::QBuffer *buffer = m_buffers.value(accessorIt->bufferViewName, nullptr);
+                if (Q_UNLIKELY(!buffer)) {
+                    qCWarning(GLTFGeometryLoaderLog, "unknown buffer-view: %ls processing accessor: %ls",
+                              qUtf16PrintableImpl(accessorIt->bufferViewName), qUtf16PrintableImpl(id));
+                    continue;
+                }
+
+                QAttribute *attribute = new QAttribute(buffer,
+                                                       accessorIt->type,
+                                                       accessorIt->dataSize,
+                                                       accessorIt->count,
+                                                       accessorIt->offset,
+                                                       accessorIt->stride);
+                attribute->setAttributeType(QAttribute::IndexAttribute);
+                meshGeometry->addAttribute(attribute);
+            }
+        } // of has indices
+
+        m_geometry = meshGeometry;
+
+        break;
+    } // of primitives iteration
+}
+
+void GLTFGeometryLoader::loadBufferData()
+{
+    for (auto &bufferData : m_bufferDatas) {
+        if (!bufferData.data) {
+            bufferData.data = new QByteArray(resolveLocalData(bufferData.path));
+        }
+    }
+}
+
+void GLTFGeometryLoader::unloadBufferData()
+{
+    for (const auto &bufferData : qAsConst(m_bufferDatas)) {
+        QByteArray *data = bufferData.data;
+        delete data;
+    }
+}
+
+QByteArray GLTFGeometryLoader::resolveLocalData(const QString &path) const
+{
+    QDir d(m_basePath);
+    Q_ASSERT(d.exists());
+
+    QString absPath = d.absoluteFilePath(path);
+    QFile f(absPath);
+    f.open(QIODevice::ReadOnly);
+    return f.readAll();
+}
+
+QAttribute::VertexBaseType GLTFGeometryLoader::accessorTypeFromJSON(int componentType)
+{
+    if (componentType == GL_BYTE) {
+        return QAttribute::Byte;
+    } else if (componentType == GL_UNSIGNED_BYTE) {
+        return QAttribute::UnsignedByte;
+    } else if (componentType == GL_SHORT) {
+        return QAttribute::Short;
+    } else if (componentType == GL_UNSIGNED_SHORT) {
+        return QAttribute::UnsignedShort;
+    } else if (componentType == GL_UNSIGNED_INT) {
+        return QAttribute::UnsignedInt;
+    } else if (componentType == GL_FLOAT) {
+        return QAttribute::Float;
+    }
+
+    //There shouldn't be an invalid case here
+    qCWarning(GLTFGeometryLoaderLog, "unsupported accessor type %d", componentType);
+    return QAttribute::Float;
+}
+
+uint GLTFGeometryLoader::accessorDataSizeFromJson(const QString &type)
+{
+    QString typeName = type.toUpper();
+    if (typeName == QLatin1String("SCALAR"))
+        return 1;
+    if (typeName == QLatin1String("VEC2"))
+        return 2;
+    if (typeName == QLatin1String("VEC3"))
+        return 3;
+    if (typeName == QLatin1String("VEC4"))
+        return 4;
+    if (typeName == QLatin1String("MAT2"))
+        return 4;
+    if (typeName == QLatin1String("MAT3"))
+        return 9;
+    if (typeName == QLatin1String("MAT4"))
+        return 16;
+
+    return 0;
+}
+
+} // namespace Qt3DRender
+
+QT_END_NAMESPACE
diff --git a/src/plugins/geometryloaders/gltf/gltfgeometryloader.h b/src/plugins/geometryloaders/gltf/gltfgeometryloader.h
new file mode 100644
index 000000000..b2245b8ab
--- /dev/null
+++ b/src/plugins/geometryloaders/gltf/gltfgeometryloader.h
@@ -0,0 +1,168 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 Klaralvdalens Datakonsult AB (KDAB).
+** 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef GLTFGEOMETRYLOADER_H
+#define GLTFGEOMETRYLOADER_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists for the convenience
+// of other Qt classes.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtCore/QJsonDocument>
+
+#include <Qt3DRender/private/qgeometryloaderinterface_p.h>
+#include <Qt3DRender/qattribute.h>
+#include <Qt3DRender/qbuffer.h>
+
+#include <private/qlocale_tools_p.h>
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3DRender {
+
+#define GLTFGEOMETRYLOADER_EXT QLatin1String("gltf")
+#define JSONGEOMETRYLOADER_EXT QLatin1String("json")
+#define QGLTFGEOMETRYLOADER_EXT QLatin1String("qgltf")
+
+class QCamera;
+class QCameraLens;
+class QMaterial;
+class QShaderProgram;
+class QEffect;
+class QAbstractTexture;
+class QRenderState;
+class QTechnique;
+class QParameter;
+class QGeometryRenderer;
+class QGeometry;
+
+class GLTFGeometryLoader : public QGeometryLoaderInterface
+{
+    class BufferData
+    {
+    public:
+        BufferData();
+        explicit BufferData(const QJsonObject &json);
+
+        quint64 length;
+        QString path;
+        QByteArray *data;
+        // type if ever useful
+    };
+
+    class ParameterData
+    {
+    public:
+        ParameterData();
+        explicit ParameterData(const QJsonObject &json);
+
+        QString semantic;
+        int type;
+    };
+
+    class AccessorData
+    {
+    public:
+        AccessorData();
+        explicit AccessorData(const QJsonObject &json);
+
+        QString bufferViewName;
+        QAttribute::VertexBaseType type;
+        uint dataSize;
+        int count;
+        int offset;
+        int stride;
+    };
+
+    Q_OBJECT
+public:
+    GLTFGeometryLoader();
+    ~GLTFGeometryLoader();
+
+    QGeometry *geometry() const Q_DECL_FINAL;
+
+    bool load(QIODevice *ioDev, const QString &subMesh = QString()) Q_DECL_FINAL;
+
+protected:
+    void setBasePath(const QString &path);
+    bool setJSON(const QJsonDocument &json);
+
+    static QString standardAttributeNameFromSemantic(const QString &semantic);
+
+    void parse();
+    void cleanup();
+
+    void processJSONBuffer(const QString &id, const QJsonObject &json);
+    void processJSONBufferView(const QString &id, const QJsonObject &json);
+    void processJSONAccessor(const QString &id, const QJsonObject &json);
+    void processJSONMesh(const QString &id, const QJsonObject &json);
+
+    void loadBufferData();
+    void unloadBufferData();
+
+    QByteArray resolveLocalData(const QString &path) const;
+
+    static QAttribute::VertexBaseType accessorTypeFromJSON(int componentType);
+    static uint accessorDataSizeFromJson(const QString &type);
+
+private:
+    QJsonDocument m_json;
+    QString m_basePath;
+    QString m_mesh;
+
+    QHash<QString, AccessorData> m_accessorDict;
+
+    QHash<QString, BufferData> m_bufferDatas;
+    QHash<QString, Qt3DRender::QBuffer*> m_buffers;
+
+    QGeometry *m_geometry;
+};
+
+} // namespace Qt3DRender
+
+QT_END_NAMESPACE
+
+#endif // GLTFGEOMETRYLOADER_H
diff --git a/src/plugins/geometryloaders/gltf/main.cpp b/src/plugins/geometryloaders/gltf/main.cpp
new file mode 100644
index 000000000..71289368a
--- /dev/null
+++ b/src/plugins/geometryloaders/gltf/main.cpp
@@ -0,0 +1,71 @@
+/****************************************************************************
+**
+** 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 <Qt3DRender/private/qgeometryloaderfactory_p.h>
+
+#include "gltfgeometryloader.h"
+
+QT_BEGIN_NAMESPACE
+
+class GLTFGeometryLoaderPlugin : public Qt3DRender::QGeometryLoaderFactory
+{
+    Q_OBJECT
+    Q_PLUGIN_METADATA(IID QGeometryLoaderFactory_iid FILE "gltf.json")
+public:
+
+    QStringList keys() const Q_DECL_OVERRIDE
+    {
+        return QStringList() << GLTFGEOMETRYLOADER_EXT
+                             << JSONGEOMETRYLOADER_EXT
+                             << QGLTFGEOMETRYLOADER_EXT;
+    }
+
+    Qt3DRender::QGeometryLoaderInterface *create(const QString &ext) Q_DECL_OVERRIDE
+    {
+        if ((ext.compare(GLTFGEOMETRYLOADER_EXT, Qt::CaseInsensitive) == 0) ||
+            (ext.compare(JSONGEOMETRYLOADER_EXT, Qt::CaseInsensitive) == 0) ||
+            (ext.compare(QGLTFGEOMETRYLOADER_EXT, Qt::CaseInsensitive) == 0))
+            return new Qt3DRender::GLTFGeometryLoader;
+        return nullptr;
+    }
+};
+
+QT_END_NAMESPACE
+
+#include "main.moc"
diff --git a/tests/auto/render/geometryloaders/cube.gltf b/tests/auto/render/geometryloaders/cube.gltf
new file mode 100644
index 000000000..c60ae4ad9
--- /dev/null
+++ b/tests/auto/render/geometryloaders/cube.gltf
@@ -0,0 +1,263 @@
+{
+  "accessors": {
+    "accessor_index_0": {
+      "bufferView": "bufferView_1",
+      "byteOffset": 0,
+      "byteStride": 0,
+      "componentType": 5123,
+      "count": 36,
+      "type": "SCALAR",
+      "min": [
+        0
+      ],
+      "max": [
+        23
+      ]
+    },
+    "accessor_position": {
+      "bufferView": "bufferView_0",
+      "byteOffset": 0,
+      "byteStride": 0,
+      "componentType": 5126,
+      "count": 24,
+      "min": [
+        -1,
+        -1,
+        -1
+      ],
+      "max": [
+        1,
+        1,
+        1.0000009536743164
+      ],
+      "type": "VEC3"
+    },
+    "accessor_normal": {
+      "bufferView": "bufferView_0",
+      "byteOffset": 288,
+      "byteStride": 0,
+      "componentType": 5126,
+      "count": 24,
+      "type": "VEC3",
+      "min": [
+        -1,
+        -1,
+        -1
+      ],
+      "max": [
+        1,
+        1,
+        1
+      ]
+    }
+  },
+  "asset": {
+    "generator": "OBJ2GLTF",
+    "premultipliedAlpha": true,
+    "profile": {
+      "api": "WebGL",
+      "version": "1.0"
+    },
+    "version": "1.0"
+  },
+  "buffers": {
+    "cube_buffer": {
+      "type": "arraybuffer",
+      "byteLength": 648,
+      "uri": "cube_buffer.bin"
+    }
+  },
+  "bufferViews": {
+    "bufferView_0": {
+      "buffer": "cube_buffer",
+      "byteLength": 576,
+      "byteOffset": 0,
+      "target": 34962
+    },
+    "bufferView_1": {
+      "buffer": "cube_buffer",
+      "byteLength": 72,
+      "byteOffset": 576,
+      "target": 34963
+    }
+  },
+  "images": {},
+  "materials": {
+    "material_czmDefaultMat": {
+      "name": "czmDefaultMat",
+      "extensions": {},
+      "values": {
+        "ambient": [
+          0,
+          0,
+          0,
+          1
+        ],
+        "diffuse": [
+          0.5,
+          0.5,
+          0.5,
+          1
+        ],
+        "emission": [
+          0,
+          0,
+          0,
+          1
+        ],
+        "specular": [
+          0,
+          0,
+          0,
+          1
+        ],
+        "shininess": 0,
+        "transparency": 1
+      },
+      "technique": "technique0"
+    }
+  },
+  "meshes": {
+    "mesh_cube": {
+      "name": "cube",
+      "primitives": [
+        {
+          "attributes": {
+            "POSITION": "accessor_position",
+            "NORMAL": "accessor_normal"
+          },
+          "indices": "accessor_index_0",
+          "material": "material_czmDefaultMat",
+          "mode": 4
+        }
+      ]
+    }
+  },
+  "nodes": {
+    "rootNode": {
+      "children": [],
+      "meshes": [
+        "mesh_cube"
+      ],
+      "matrix": [
+        1,
+        0,
+        0,
+        0,
+        0,
+        1,
+        0,
+        0,
+        0,
+        0,
+        1,
+        0,
+        0,
+        0,
+        0,
+        1
+      ]
+    }
+  },
+  "samplers": {},
+  "scene": "scene_cube",
+  "scenes": {
+    "scene_cube": {
+      "nodes": [
+        "rootNode"
+      ]
+    }
+  },
+  "textures": {},
+  "extensionsUsed": [],
+  "animations": {},
+  "cameras": {},
+  "techniques": {
+    "technique0": {
+      "attributes": {
+        "a_position": "position",
+        "a_normal": "normal"
+      },
+      "parameters": {
+        "modelViewMatrix": {
+          "semantic": "MODELVIEW",
+          "type": 35676
+        },
+        "projectionMatrix": {
+          "semantic": "PROJECTION",
+          "type": 35676
+        },
+        "normalMatrix": {
+          "semantic": "MODELVIEWINVERSETRANSPOSE",
+          "type": 35675
+        },
+        "ambient": {
+          "type": 35666
+        },
+        "diffuse": {
+          "type": 35666
+        },
+        "emission": {
+          "type": 35666
+        },
+        "specular": {
+          "type": 35666
+        },
+        "shininess": {
+          "type": 5126
+        },
+        "transparency": {
+          "type": 5126
+        },
+        "position": {
+          "semantic": "POSITION",
+          "type": 35665
+        },
+        "normal": {
+          "semantic": "NORMAL",
+          "type": 35665
+        }
+      },
+      "program": "program0",
+      "states": {
+        "enable": [
+          2884,
+          2929
+        ]
+      },
+      "uniforms": {
+        "u_modelViewMatrix": "modelViewMatrix",
+        "u_projectionMatrix": "projectionMatrix",
+        "u_normalMatrix": "normalMatrix",
+        "u_ambient": "ambient",
+        "u_diffuse": "diffuse",
+        "u_emission": "emission",
+        "u_specular": "specular",
+        "u_shininess": "shininess",
+        "u_transparency": "transparency"
+      }
+    }
+  },
+  "programs": {
+    "program0": {
+      "attributes": [
+        "a_position",
+        "a_normal"
+      ],
+      "fragmentShader": "fragmentShader0",
+      "vertexShader": "vertexShader0"
+    }
+  },
+  "shaders": {
+    "vertexShader0": {
+      "type": 35633,
+      "uri": "vertexShader0.glsl"
+    },
+    "fragmentShader0": {
+      "type": 35632,
+      "uri": "fragmentShader0.glsl"
+    }
+  },
+  "skins": {},
+  "extensions": {}
+}
diff --git a/tests/auto/render/geometryloaders/cube_buffer.bin b/tests/auto/render/geometryloaders/cube_buffer.bin
new file mode 100644
index 000000000..78e4588be
--- /dev/null
+++ b/tests/auto/render/geometryloaders/cube_buffer.bin
diff --git a/tests/auto/render/geometryloaders/geometryloaders.qrc b/tests/auto/render/geometryloaders/geometryloaders.qrc
index a2418d2fd..f052420d5 100644
--- a/tests/auto/render/geometryloaders/geometryloaders.qrc
+++ b/tests/auto/render/geometryloaders/geometryloaders.qrc
@@ -3,5 +3,7 @@
         <file>cube.obj</file>
         <file>cube.ply</file>
         <file>cube.stl</file>
+        <file>cube.gltf</file>
+        <file>cube_buffer.bin</file>
     </qresource>
 </RCC>
diff --git a/tests/auto/render/geometryloaders/tst_geometryloaders.cpp b/tests/auto/render/geometryloaders/tst_geometryloaders.cpp
index 61910c417..03c3abc31 100644
--- a/tests/auto/render/geometryloaders/tst_geometryloaders.cpp
+++ b/tests/auto/render/geometryloaders/tst_geometryloaders.cpp
@@ -61,6 +61,7 @@ private Q_SLOTS:
     void testOBJLoader();
     void testPLYLoader();
     void testSTLLoader();
+    void testGLTFLoader();
 };
 
 void tst_geometryloaders::testOBJLoader()
@@ -173,6 +174,45 @@ void tst_geometryloaders::testSTLLoader()
     file.close();
 }
 
+void tst_geometryloaders::testGLTFLoader()
+{
+    QScopedPointer<QGeometryLoaderInterface> loader;
+    loader.reset(qLoadPlugin<QGeometryLoaderInterface, QGeometryLoaderFactory>(geometryLoader(), QStringLiteral("gltf")));
+    QVERIFY(loader);
+    if (!loader)
+        return;
+
+    QFile file(QStringLiteral(":/cube.gltf"));
+    if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
+        qDebug("Could not open test file for reading");
+        return;
+    }
+
+    bool loaded = loader->load(&file, QStringLiteral("Cube"));
+    QVERIFY(loaded);
+    if (!loaded)
+        return;
+
+    QGeometry *geometry = loader->geometry();
+    QVERIFY(geometry);
+    if (!geometry)
+        return;
+
+    QCOMPARE(geometry->attributes().count(), 3);
+    for (QAttribute *attr : geometry->attributes()) {
+        switch (attr->attributeType()) {
+        case QAttribute::IndexAttribute:
+            QCOMPARE(attr->count(), 36u);
+            break;
+        case QAttribute::VertexAttribute:
+            QCOMPARE(attr->count(), 24u);
+            break;
+        }
+    }
+
+    file.close();
+}
+
 QTEST_MAIN(tst_geometryloaders)
 
 #include "tst_geometryloaders.moc"