add assimp submodule

1 files changed, 834 insertions, 0 deletions

diff --git a/src/mesh/assimp-master/test/unit/utglTF2ImportExport.cpp b/src/mesh/assimp-master/test/unit/utglTF2ImportExport.cpp
new file mode 100644
index 0000000..00f76aa
--- /dev/null
+++ b/src/mesh/assimp-master/test/unit/utglTF2ImportExport.cpp
@@ -0,0 +1,834 @@
+/*
+---------------------------------------------------------------------------
+Open Asset Import Library (assimp)
+---------------------------------------------------------------------------
+
+Copyright (c) 2006-2022, assimp team
+
+All rights reserved.
+
+Redistribution and use of this software in source and binary forms,
+with or without modification, are permitted provided that the following
+conditions are met:
+
+* Redistributions of source code must retain the above
+copyright notice, this list of conditions and the
+following disclaimer.
+
+* Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the
+following disclaimer in the documentation and/or other
+materials provided with the distribution.
+
+* Neither the name of the assimp team, nor the names of its
+contributors may be used to endorse or promote products
+derived from this software without specific prior
+written permission of the assimp team.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+---------------------------------------------------------------------------
+*/
+#include "AbstractImportExportBase.h"
+#include "UnitTestPCH.h"
+
+#include <assimp/commonMetaData.h>
+#include <assimp/postprocess.h>
+#include <assimp/scene.h>
+#include <assimp/Exporter.hpp>
+#include <assimp/Importer.hpp>
+#include <assimp/LogStream.hpp>
+#include <assimp/DefaultLogger.hpp>
+
+#include <rapidjson/schema.h>
+
+#include <array>
+
+#include <assimp/material.h>
+#include <assimp/GltfMaterial.h>
+
+using namespace Assimp;
+
+class utglTF2ImportExport : public AbstractImportExportBase {
+public:
+    virtual bool importerMatTest(const char *file, bool spec_gloss, std::array<aiTextureMapMode, 2> exp_modes = { aiTextureMapMode_Wrap, aiTextureMapMode_Wrap }) {
+        Assimp::Importer importer;
+        const aiScene *scene = importer.ReadFile(file, aiProcess_ValidateDataStructure);
+        EXPECT_NE(scene, nullptr);
+        if (!scene) {
+            return false;
+        }
+
+        EXPECT_TRUE(scene->HasMaterials());
+        if (!scene->HasMaterials()) {
+            return false;
+        }
+        const aiMaterial *material = scene->mMaterials[0];
+
+        // This Material should be a PBR
+        aiShadingMode shadingMode;
+        EXPECT_EQ(aiReturn_SUCCESS, material->Get(AI_MATKEY_SHADING_MODEL, shadingMode));
+        EXPECT_EQ(aiShadingMode_PBR_BRDF, shadingMode);
+
+        // Should import the texture as diffuse and as base color
+        aiString path;
+        std::array<aiTextureMapMode,2> modes;
+        EXPECT_EQ(aiReturn_SUCCESS, material->GetTexture(aiTextureType_DIFFUSE, 0, &path, nullptr, nullptr,
+                                            nullptr, nullptr, modes.data()));
+        EXPECT_STREQ(path.C_Str(), "CesiumLogoFlat.png");
+        EXPECT_EQ(exp_modes, modes);
+
+        // Also as Base Color
+        EXPECT_EQ(aiReturn_SUCCESS, material->GetTexture(aiTextureType_BASE_COLOR, 0, &path, nullptr, nullptr,
+                                            nullptr, nullptr, modes.data()));
+        EXPECT_STREQ(path.C_Str(), "CesiumLogoFlat.png");
+        EXPECT_EQ(exp_modes, modes);
+
+        // Should have a MetallicFactor (default is 1.0)
+        ai_real metal_factor = ai_real(0.5);
+        EXPECT_EQ(aiReturn_SUCCESS, material->Get(AI_MATKEY_METALLIC_FACTOR, metal_factor));
+        EXPECT_EQ(ai_real(0.0), metal_factor);
+
+        // And a roughness factor (default is 1.0)
+        ai_real roughness_factor = ai_real(0.5);
+        EXPECT_EQ(aiReturn_SUCCESS, material->Get(AI_MATKEY_ROUGHNESS_FACTOR, roughness_factor));
+        EXPECT_EQ(ai_real(1.0), roughness_factor);
+
+        aiColor3D spec_color = { 0, 0, 0 };
+        ai_real glossiness = ai_real(0.5);
+        if (spec_gloss) {
+            EXPECT_EQ(aiReturn_SUCCESS, material->Get(AI_MATKEY_COLOR_SPECULAR, spec_color));
+            constexpr ai_real spec_val(0.20000000298023225); // From the file
+            EXPECT_EQ(spec_val, spec_color.r);
+            EXPECT_EQ(spec_val, spec_color.g);
+            EXPECT_EQ(spec_val, spec_color.b);
+            EXPECT_EQ(aiReturn_SUCCESS, material->Get(AI_MATKEY_GLOSSINESS_FACTOR, glossiness));
+            EXPECT_EQ(ai_real(1.0), glossiness);
+        } else {
+            EXPECT_EQ(aiReturn_FAILURE, material->Get(AI_MATKEY_COLOR_SPECULAR, spec_color));
+            EXPECT_EQ(aiReturn_FAILURE, material->Get(AI_MATKEY_GLOSSINESS_FACTOR, glossiness));
+        }
+
+        return true;
+    }
+
+    virtual bool binaryImporterTest() {
+        Assimp::Importer importer;
+        const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/2CylinderEngine-glTF-Binary/2CylinderEngine.glb",
+                aiProcess_ValidateDataStructure);
+        return nullptr != scene;
+    }
+
+#ifndef ASSIMP_BUILD_NO_EXPORT
+    virtual bool exporterTest() {
+        Assimp::Importer importer;
+        Assimp::Exporter exporter;
+        const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF/BoxTextured.gltf",
+                aiProcess_ValidateDataStructure);
+        EXPECT_NE(nullptr, scene);
+        EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "gltf2", ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF/BoxTextured_out.gltf"));
+
+        return true;
+    }
+#endif // ASSIMP_BUILD_NO_EXPORT
+};
+
+TEST_F(utglTF2ImportExport, importglTF2FromFileTest) {
+    EXPECT_TRUE(importerMatTest(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF/BoxTextured.gltf", false, {aiTextureMapMode_Mirror, aiTextureMapMode_Clamp}));
+}
+
+TEST_F(utglTF2ImportExport, importBinaryglTF2FromFileTest) {
+    EXPECT_TRUE(binaryImporterTest());
+}
+
+TEST_F(utglTF2ImportExport, importglTF2_KHR_materials_pbrSpecularGlossiness) {
+    EXPECT_TRUE(importerMatTest(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF-pbrSpecularGlossiness/BoxTextured.gltf", true));
+}
+
+void VerifyClearCoatScene(const aiScene *scene) {
+        ASSERT_NE(nullptr, scene);
+
+    ASSERT_TRUE(scene->HasMaterials());
+
+    // Find a specific Clearcoat material and check the values
+    const aiString partial_coated("Partial_Coated");
+    bool found_partial_coat = false;
+    for (size_t i = 0; i < scene->mNumMaterials; ++i) {
+        const aiMaterial *material = scene->mMaterials[i];
+        ASSERT_NE(nullptr, material);
+        if (material->GetName() == partial_coated) {
+            found_partial_coat = true;
+
+            ai_real clearcoat_factor(0.0f);
+            EXPECT_EQ(aiReturn_SUCCESS, material->Get(AI_MATKEY_CLEARCOAT_FACTOR, clearcoat_factor));
+            EXPECT_EQ(ai_real(1.0f), clearcoat_factor);
+
+            ai_real clearcoat_rough_factor(0.0f);
+            EXPECT_EQ(aiReturn_SUCCESS, material->Get(AI_MATKEY_CLEARCOAT_ROUGHNESS_FACTOR, clearcoat_rough_factor));
+            EXPECT_EQ(ai_real(0.03f), clearcoat_rough_factor);
+
+            // Should import the texture as diffuse and as base color
+            aiString path;
+            std::array<aiTextureMapMode, 2> modes;
+            static const std::array<aiTextureMapMode, 2> exp_modes = { aiTextureMapMode_Wrap, aiTextureMapMode_Wrap };
+            EXPECT_EQ(aiReturn_SUCCESS, material->GetTexture(AI_MATKEY_CLEARCOAT_TEXTURE, &path, nullptr, nullptr,
+                                                nullptr, nullptr, modes.data()));
+            EXPECT_STREQ(path.C_Str(), "PartialCoating.png");
+            EXPECT_EQ(exp_modes, modes);
+        }
+    }
+    EXPECT_TRUE(found_partial_coat);
+}
+
+TEST_F(utglTF2ImportExport, importglTF2_KHR_materials_clearcoat) {
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/ClearCoat-glTF/ClearCoatTest.gltf", aiProcess_ValidateDataStructure);
+    VerifyClearCoatScene(scene);
+}
+
+#ifndef ASSIMP_BUILD_NO_EXPORT
+
+TEST_F(utglTF2ImportExport, importglTF2AndExport_KHR_materials_clearcoat) {
+    {
+        Assimp::Importer importer;
+        Assimp::Exporter exporter;
+        const aiScene* scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/ClearCoat-glTF/ClearCoatTest.gltf", aiProcess_ValidateDataStructure);
+        ASSERT_NE(nullptr, scene);
+        // Export
+        EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "glb2", ASSIMP_TEST_MODELS_DIR "/glTF2/ClearCoat-glTF/ClearCoatTest_out.glb"));
+    }
+
+    // And re-import
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/ClearCoat-glTF/ClearCoatTest_out.glb", aiProcess_ValidateDataStructure);
+    VerifyClearCoatScene(scene);
+}
+
+TEST_F(utglTF2ImportExport, importglTF2AndExport_KHR_materials_pbrSpecularGlossiness) {
+    Assimp::Importer importer;
+    Assimp::Exporter exporter;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF-pbrSpecularGlossiness/BoxTextured.gltf",
+            aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    // Export
+    EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "glb2", ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF-pbrSpecularGlossiness/BoxTextured_out.glb"));
+
+    // And re-import
+    EXPECT_TRUE(importerMatTest(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF-pbrSpecularGlossiness/BoxTextured_out.glb", true));
+}
+
+TEST_F(utglTF2ImportExport, importglTF2AndExportToOBJ) {
+    Assimp::Importer importer;
+    Assimp::Exporter exporter;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF/BoxTextured.gltf",
+            aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "obj", ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF/BoxTextured_out.obj"));
+}
+
+TEST_F(utglTF2ImportExport, importglTF2EmbeddedAndExportToOBJ) {
+    Assimp::Importer importer;
+    Assimp::Exporter exporter;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF-Embedded/BoxTextured.gltf",
+            aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "obj", ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF-Embedded/BoxTextured_out.obj"));
+}
+
+#endif // ASSIMP_BUILD_NO_EXPORT
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModePointsWithoutIndices) {
+    Assimp::Importer importer;
+    //Points without indices
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_00.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 1024u);
+    for (unsigned int i = 0; i < scene->mMeshes[0]->mNumFaces; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mNumIndices, 1u);
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[0], i);
+    }
+}
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModeLinesWithoutIndices) {
+    Assimp::Importer importer;
+    //Lines without indices
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_01.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 8u);
+    for (unsigned int i = 0; i < scene->mMeshes[0]->mNumFaces; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mNumIndices, 2u);
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[0], i * 2u);
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[1], i * 2u + 1u);
+    }
+}
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModeLinesLoopWithoutIndices) {
+    Assimp::Importer importer;
+    //Lines loop without indices
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_02.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 4u);
+
+    std::array<unsigned int, 5> l1 = { { 0u, 1u, 2u, 3u, 0u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mNumIndices, 2u);
+    for (unsigned int i = 0; i < scene->mMeshes[0]->mNumFaces; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mNumIndices, 2u);
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[0], l1[i]);
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[1], l1[i + 1u]);
+    }
+}
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModeLinesStripWithoutIndices) {
+    Assimp::Importer importer;
+    //Lines strip without indices
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_03.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 5u);
+
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mNumIndices, 2u);
+    for (unsigned int i = 0; i < scene->mMeshes[0]->mNumFaces; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mNumIndices, 2u);
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[0], i);
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[1], i + 1u);
+    }
+}
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModeTrianglesStripWithoutIndices) {
+    Assimp::Importer importer;
+    //Triangles strip without indices
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_04.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumFaces, 2u);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 4u);
+    std::array<unsigned int, 3> f1 = { { 0u, 1u, 2u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mNumIndices, 3u);
+    for (unsigned int i = 0; i < 3; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mIndices[i], f1[i]);
+    }
+
+    std::array<unsigned int, 3> f2 = { { 2u, 1u, 3u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[1].mNumIndices, 3u);
+    for (size_t i = 0; i < 3; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[1].mIndices[i], f2[i]);
+    }
+}
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModeTrianglesFanWithoutIndices) {
+    Assimp::Importer importer;
+    //Triangles fan without indices
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_05.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumFaces, 2u);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 4u);
+    std::array<unsigned int, 3> f1 = { { 0u, 1u, 2u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mNumIndices, 3u);
+    for (size_t i = 0; i < 3; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mIndices[i], f1[i]);
+    }
+
+    std::array<unsigned int, 3> f2 = { { 0u, 2u, 3u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[1].mNumIndices, 3u);
+    for (size_t i = 0; i < 3; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[1].mIndices[i], f2[i]);
+    }
+}
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModeTrianglesWithoutIndices) {
+    Assimp::Importer importer;
+    //Triangles without indices
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_06.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumFaces, 2u);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 6u);
+    std::array<unsigned int, 3> f1 = { { 0u, 1u, 2u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mNumIndices, 3u);
+    for (size_t i = 0; i < 3; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mIndices[i], f1[i]);
+    }
+
+    std::array<unsigned int, 3> f2 = { { 3u, 4u, 5u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[1].mNumIndices, 3u);
+    for (size_t i = 0; i < 3; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[1].mIndices[i], f2[i]);
+    }
+}
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModePoints) {
+    Assimp::Importer importer;
+    //Line loop
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_07.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 1024u);
+    for (unsigned int i = 0; i < scene->mMeshes[0]->mNumFaces; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mNumIndices, 1u);
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[0], i);
+    }
+}
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModeLines) {
+    Assimp::Importer importer;
+    //Lines
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_08.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 4u);
+    std::array<unsigned int, 5> l1 = { { 0u, 3u, 2u, 1u, 0u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mNumIndices, 2u);
+    for (unsigned int i = 0; i < scene->mMeshes[0]->mNumFaces; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[0], l1[i]);
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[1], l1[i + 1]);
+    }
+}
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModeLineLoop) {
+    Assimp::Importer importer;
+    //Line loop
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_09.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 4u);
+    std::array<unsigned int, 5> l1 = { { 0, 3u, 2u, 1u, 0u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mNumIndices, 2u);
+    for (unsigned int i = 0; i < scene->mMeshes[0]->mNumFaces; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[0], l1[i]);
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[1], l1[i + 1]);
+    }
+}
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModeLineStrip) {
+    Assimp::Importer importer;
+    //Lines Strip
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_10.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 4u);
+    std::array<unsigned int, 5> l1 = { { 0u, 3u, 2u, 1u, 0u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mNumIndices, 2u);
+    for (unsigned int i = 0; i < scene->mMeshes[0]->mNumFaces; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[0], l1[i]);
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[i].mIndices[1], l1[i + 1]);
+    }
+}
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModeTrianglesStrip) {
+    Assimp::Importer importer;
+    //Triangles strip
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_11.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumFaces, 2u);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 4u);
+    std::array<unsigned int, 3> f1 = { { 0u, 3u, 1u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mNumIndices, 3u);
+    for (size_t i = 0; i < 3; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mIndices[i], f1[i]);
+    }
+
+    std::array<unsigned int, 3> f2 = { { 1u, 3u, 2u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[1].mNumIndices, 3u);
+    for (size_t i = 0; i < 3; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[1].mIndices[i], f2[i]);
+    }
+}
+
+TEST_F(utglTF2ImportExport, importglTF2PrimitiveModeTrianglesFan) {
+    Assimp::Importer importer;
+    //Triangles fan
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Asset-Generator/Mesh_PrimitiveMode/Mesh_PrimitiveMode_12.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 4u);
+    EXPECT_EQ(scene->mMeshes[0]->mNumFaces, 2u);
+    std::array<unsigned int, 3> f1 = { { 0u, 3u, 2u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mNumIndices, 3u);
+    for (size_t i = 0; i < 3; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[0].mIndices[i], f1[i]);
+    }
+
+    std::array<unsigned int, 3> f2 = { { 0u, 2u, 1u } };
+    EXPECT_EQ(scene->mMeshes[0]->mFaces[1].mNumIndices, 3u);
+    for (size_t i = 0; i < 3; ++i) {
+        EXPECT_EQ(scene->mMeshes[0]->mFaces[1].mIndices[i], f2[i]);
+    }
+}
+
+std::vector<char> ReadFile(const char *name) {
+    std::vector<char> ret;
+
+    FILE *p = ::fopen(name, "r");
+    if (nullptr == p) {
+        return ret;
+    }
+
+    ::fseek(p, 0, SEEK_END);
+    const size_t size = ::ftell(p);
+    ::fseek(p, 0, SEEK_SET);
+
+    ret.resize(size);
+    const size_t readSize = ::fread(&ret[0], 1, size, p);
+    EXPECT_EQ(readSize, size);
+    ::fclose(p);
+
+    return ret;
+}
+
+TEST_F(utglTF2ImportExport, importglTF2FromMemory) {
+    /*const auto flags = aiProcess_CalcTangentSpace | aiProcess_Triangulate | aiProcess_RemoveComponent |
+        aiProcess_GenSmoothNormals | aiProcess_PreTransformVertices | aiProcess_FixInfacingNormals |
+        aiProcess_FindDegenerates | aiProcess_GenUVCoords | aiProcess_SortByPType;
+    const auto& buff = ReadFile("C:\\Users\\kimkulling\\Downloads\\camel\\camel\\scene.gltf");*/
+    /*const aiScene* Scene = ::aiImportFileFromMemory(&buff[0], buff.size(), flags, ".gltf");
+    EXPECT_EQ( nullptr, Scene );*/
+}
+
+TEST_F(utglTF2ImportExport, bug_import_simple_skin) {
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/simple_skin/simple_skin.gltf",
+            aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+}
+
+TEST_F(utglTF2ImportExport, import_cameras) {
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/cameras/Cameras.gltf",
+            aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+}
+
+TEST_F(utglTF2ImportExport, incorrect_vertex_arrays) {
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/IncorrectVertexArrays/Cube.gltf",
+            aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 36u);
+    EXPECT_EQ(scene->mMeshes[0]->mNumFaces, 12u);
+    EXPECT_EQ(scene->mMeshes[1]->mNumVertices, 35u);
+    EXPECT_EQ(scene->mMeshes[1]->mNumFaces, 11u);
+    EXPECT_EQ(scene->mMeshes[2]->mNumVertices, 36u);
+    EXPECT_EQ(scene->mMeshes[2]->mNumFaces, 18u);
+    EXPECT_EQ(scene->mMeshes[3]->mNumVertices, 35u);
+    EXPECT_EQ(scene->mMeshes[3]->mNumFaces, 17u);
+    EXPECT_EQ(scene->mMeshes[4]->mNumVertices, 36u);
+    EXPECT_EQ(scene->mMeshes[4]->mNumFaces, 12u);
+    EXPECT_EQ(scene->mMeshes[5]->mNumVertices, 35u);
+    EXPECT_EQ(scene->mMeshes[5]->mNumFaces, 11u);
+    EXPECT_EQ(scene->mMeshes[6]->mNumVertices, 36u);
+    EXPECT_EQ(scene->mMeshes[6]->mNumFaces, 18u);
+    EXPECT_EQ(scene->mMeshes[7]->mNumVertices, 35u);
+    EXPECT_EQ(scene->mMeshes[7]->mNumFaces, 17u);
+}
+
+TEST_F(utglTF2ImportExport, texture_transform_test) {
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/textureTransform/TextureTransformTest.gltf",
+            aiProcess_ValidateDataStructure);
+    EXPECT_NE(nullptr, scene);
+}
+
+#ifndef ASSIMP_BUILD_NO_EXPORT
+TEST_F(utglTF2ImportExport, exportglTF2FromFileTest) {
+    EXPECT_TRUE(exporterTest());
+}
+
+TEST_F(utglTF2ImportExport, crash_in_anim_mesh_destructor) {
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Sample-Models/AnimatedMorphCube-glTF/AnimatedMorphCube.gltf",
+            aiProcess_ValidateDataStructure);
+    ASSERT_NE(nullptr, scene);
+    Assimp::Exporter exporter;
+    ASSERT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "glb2", ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Sample-Models/AnimatedMorphCube-glTF/AnimatedMorphCube_out.glTF"));
+}
+
+TEST_F(utglTF2ImportExport, error_string_preserved) {
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/MissingBin/BoxTextured.gltf",
+            aiProcess_ValidateDataStructure);
+    ASSERT_EQ(nullptr, scene);
+    std::string error = importer.GetErrorString();
+    ASSERT_NE(error.find("BoxTextured0.bin"), std::string::npos) << "Error string should contain an error about missing .bin file";
+}
+
+TEST_F(utglTF2ImportExport, export_bad_accessor_bounds) {
+    Assimp::Importer importer;
+    Assimp::Exporter exporter;
+    const aiScene* scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxWithInfinites-glTF-Binary/BoxWithInfinites.glb", aiProcess_ValidateDataStructure);
+    ASSERT_NE(scene, nullptr);
+
+    EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "glb2", ASSIMP_TEST_MODELS_DIR "/glTF2/BoxWithInfinites-glTF-Binary/BoxWithInfinites_out.glb"));
+    EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "gltf2", ASSIMP_TEST_MODELS_DIR "/glTF2/BoxWithInfinites-glTF-Binary/BoxWithInfinites_out.gltf"));
+}
+
+TEST_F(utglTF2ImportExport, export_normalized_normals) {
+    Assimp::Importer importer;
+    Assimp::Exporter exporter;
+    const aiScene* scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxBadNormals-glTF-Binary/BoxBadNormals.glb", aiProcess_ValidateDataStructure);
+    ASSERT_NE(scene, nullptr);
+    EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "glb2", ASSIMP_TEST_MODELS_DIR "/glTF2/BoxBadNormals-glTF-Binary/BoxBadNormals_out.glb"));
+
+    // load in again and ensure normal-length normals but no Nan's or Inf's introduced
+    scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxBadNormals-glTF-Binary/BoxBadNormals_out.glb", aiProcess_ValidateDataStructure);
+    for ( auto i = 0u; i < scene->mMeshes[0]->mNumVertices; ++i ) {
+        const auto length = scene->mMeshes[0]->mNormals[i].Length();
+        EXPECT_TRUE(abs(length) < 1e-6 || abs(length - 1) < ai_epsilon);
+    }
+}
+
+#endif // ASSIMP_BUILD_NO_EXPORT
+
+TEST_F(utglTF2ImportExport, sceneMetadata) {
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF/BoxTextured.gltf",
+            aiProcess_ValidateDataStructure);
+    ASSERT_NE(scene, nullptr);
+    ASSERT_NE(scene->mMetaData, nullptr);
+    {
+        ASSERT_TRUE(scene->mMetaData->HasKey(AI_METADATA_SOURCE_FORMAT));
+        aiString format;
+        ASSERT_TRUE(scene->mMetaData->Get(AI_METADATA_SOURCE_FORMAT, format));
+        ASSERT_EQ(strcmp(format.C_Str(), "glTF2 Importer"), 0);
+    }
+    {
+        ASSERT_TRUE(scene->mMetaData->HasKey(AI_METADATA_SOURCE_FORMAT_VERSION));
+        aiString version;
+        ASSERT_TRUE(scene->mMetaData->Get(AI_METADATA_SOURCE_FORMAT_VERSION, version));
+        ASSERT_EQ(strcmp(version.C_Str(), "2.0"), 0);
+    }
+    {
+        ASSERT_TRUE(scene->mMetaData->HasKey(AI_METADATA_SOURCE_GENERATOR));
+        aiString generator;
+        ASSERT_TRUE(scene->mMetaData->Get(AI_METADATA_SOURCE_GENERATOR, generator));
+        ASSERT_EQ(strcmp(generator.C_Str(), "COLLADA2GLTF"), 0);
+    }
+}
+
+TEST_F(utglTF2ImportExport, texcoords) {
+
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTexcoords-glTF/boxTexcoords.gltf", aiProcess_ValidateDataStructure);
+    ASSERT_NE(scene, nullptr);
+    ASSERT_TRUE(scene->HasMaterials());
+    const aiMaterial *material = scene->mMaterials[0];
+
+    aiString path;
+    unsigned int uvIndex = 255;
+    aiTextureMapMode modes[2];
+    EXPECT_EQ(aiReturn_SUCCESS, material->GetTexture(AI_MATKEY_BASE_COLOR_TEXTURE, &path, nullptr, &uvIndex, nullptr, nullptr, modes));
+    EXPECT_STREQ(path.C_Str(), "texture.png");
+    EXPECT_EQ(uvIndex, 0u);
+
+    uvIndex = 255;
+    EXPECT_EQ(aiReturn_SUCCESS, material->GetTexture(AI_MATKEY_GLTF_PBRMETALLICROUGHNESS_METALLICROUGHNESS_TEXTURE, &path, nullptr, &uvIndex, nullptr, nullptr, modes));
+    EXPECT_STREQ(path.C_Str(), "texture.png");
+    EXPECT_EQ(uvIndex, 1u);
+}
+
+#ifndef ASSIMP_BUILD_NO_EXPORT
+
+TEST_F(utglTF2ImportExport, texcoords_export) {
+    {
+        Assimp::Importer importer;
+        Assimp::Exporter exporter;
+        const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTexcoords-glTF/boxTexcoords.gltf", aiProcess_ValidateDataStructure);
+        ASSERT_NE(scene, nullptr);
+        ASSERT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "glb2", ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTexcoords-glTF/boxTexcoords.gltf_out.glb"));
+    }
+
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTexcoords-glTF/boxTexcoords.gltf", aiProcess_ValidateDataStructure);
+    ASSERT_NE(scene, nullptr);
+
+    ASSERT_TRUE(scene->HasMaterials());
+    const aiMaterial *material = scene->mMaterials[0];
+
+    aiString path;
+    unsigned int uvIndex = 255;
+    aiTextureMapMode modes[2];
+    EXPECT_EQ(aiReturn_SUCCESS, material->GetTexture(AI_MATKEY_BASE_COLOR_TEXTURE, &path, nullptr, &uvIndex, nullptr, nullptr, modes));
+    EXPECT_STREQ(path.C_Str(), "texture.png");
+    EXPECT_EQ(uvIndex, 0u);
+
+    uvIndex = 255;
+    EXPECT_EQ(aiReturn_SUCCESS, material->GetTexture(AI_MATKEY_GLTF_PBRMETALLICROUGHNESS_METALLICROUGHNESS_TEXTURE, &path, nullptr, &uvIndex, nullptr, nullptr, modes));
+    EXPECT_STREQ(path.C_Str(), "texture.png");
+    EXPECT_EQ(uvIndex, 1u);
+}
+
+#endif // ASSIMP_BUILD_NO_EXPORT
+TEST_F(utglTF2ImportExport, recursive_nodes) {
+    Assimp::Importer importer;
+    const aiScene* scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/RecursiveNodes/RecursiveNodes.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_EQ(nullptr, scene);
+}
+
+TEST_F(utglTF2ImportExport, norootnode_noscene) {
+    Assimp::Importer importer;
+    const aiScene* scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/TestNoRootNode/NoScene.gltf", aiProcess_ValidateDataStructure);
+    ASSERT_EQ(scene, nullptr);
+}
+
+TEST_F(utglTF2ImportExport, norootnode_scenewithoutnodes) {
+    Assimp::Importer importer;
+    const aiScene* scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/TestNoRootNode/SceneWithoutNodes.gltf", aiProcess_ValidateDataStructure);
+    ASSERT_NE(scene, nullptr);
+    ASSERT_NE(scene->mRootNode, nullptr);
+}
+
+// Shall not crash!
+TEST_F(utglTF2ImportExport, norootnode_issue_3269) {
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/issue_3269/texcoord_crash.gltf", aiProcess_ValidateDataStructure);
+    ASSERT_EQ(scene, nullptr);
+}
+
+TEST_F(utglTF2ImportExport, indexOutOfRange) {
+    // The contents of an asset should not lead to an assert.
+    Assimp::Importer importer;
+
+    struct LogObserver : Assimp::LogStream {
+        bool m_observedWarning = false;
+        void write(const char *message) override {
+            m_observedWarning = m_observedWarning || std::strstr(message, "faces were dropped");
+        }
+    };
+    LogObserver logObserver;
+
+    DefaultLogger::get()->attachStream(&logObserver);
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/IndexOutOfRange/IndexOutOfRange.gltf", aiProcess_ValidateDataStructure);
+    ASSERT_NE(scene, nullptr);
+    ASSERT_NE(scene->mRootNode, nullptr);
+    ASSERT_EQ(scene->mNumMeshes, 1u);
+    EXPECT_EQ(scene->mMeshes[0]->mNumFaces, 11u);
+    DefaultLogger::get()->detachStream(&logObserver);
+    EXPECT_TRUE(logObserver.m_observedWarning);
+}
+
+TEST_F(utglTF2ImportExport, allIndicesOutOfRange) {
+    // The contents of an asset should not lead to an assert.
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/IndexOutOfRange/AllIndicesOutOfRange.gltf", aiProcess_ValidateDataStructure);
+    ASSERT_EQ(scene, nullptr);
+    std::string error = importer.GetErrorString();
+    ASSERT_NE(error.find("Mesh \"Mesh\" has no faces"), std::string::npos);
+}
+
+/////////////////////////////////
+// Draco decoding
+
+TEST_F(utglTF2ImportExport, import_dracoEncoded) {
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/draco/2CylinderEngine.gltf",
+            aiProcess_ValidateDataStructure);
+#ifndef ASSIMP_ENABLE_DRACO
+    // No draco support, scene should not load
+    ASSERT_EQ(scene, nullptr);
+#else
+    ASSERT_NE(scene, nullptr);
+    ASSERT_NE(scene->mMetaData, nullptr);
+    {
+        ASSERT_TRUE(scene->mMetaData->HasKey(AI_METADATA_SOURCE_FORMAT));
+        aiString format;
+        ASSERT_TRUE(scene->mMetaData->Get(AI_METADATA_SOURCE_FORMAT, format));
+        ASSERT_EQ(strcmp(format.C_Str(), "glTF2 Importer"), 0);
+    }
+    {
+        ASSERT_TRUE(scene->mMetaData->HasKey(AI_METADATA_SOURCE_FORMAT_VERSION));
+        aiString version;
+        ASSERT_TRUE(scene->mMetaData->Get(AI_METADATA_SOURCE_FORMAT_VERSION, version));
+        ASSERT_EQ(strcmp(version.C_Str(), "2.0"), 0);
+    }
+    {
+        ASSERT_TRUE(scene->mMetaData->HasKey(AI_METADATA_SOURCE_GENERATOR));
+        aiString generator;
+        ASSERT_TRUE(scene->mMetaData->Get(AI_METADATA_SOURCE_GENERATOR, generator));
+        ASSERT_EQ(strcmp(generator.C_Str(), "COLLADA2GLTF"), 0);
+    }
+#endif
+}
+
+TEST_F(utglTF2ImportExport, wrongTypes) {
+    // Deliberately broken version of the BoxTextured.gltf asset.
+    using tup_T = std::tuple<std::string, std::string, std::string, std::string>;
+    std::vector<tup_T> wrongTypes = {
+        { "/glTF2/wrongTypes/badArray.gltf", "array", "primitives", "meshes[0]" },
+        { "/glTF2/wrongTypes/badString.gltf", "string", "name", "scenes[0]" },
+        { "/glTF2/wrongTypes/badUint.gltf", "uint", "index", "materials[0]" },
+        { "/glTF2/wrongTypes/badNumber.gltf", "number", "scale", "materials[0]" },
+        { "/glTF2/wrongTypes/badObject.gltf", "object", "pbrMetallicRoughness", "materials[0]" },
+        { "/glTF2/wrongTypes/badExtension.gltf", "object", "KHR_texture_transform", "materials[0]" }
+    };
+    for (const auto& tuple : wrongTypes)
+    {
+        const auto& file = std::get<0>(tuple);
+        const auto& type = std::get<1>(tuple);
+        const auto& member = std::get<2>(tuple);
+        const auto& context = std::get<3>(tuple);
+        Assimp::Importer importer;
+        const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR + file , aiProcess_ValidateDataStructure);
+        ASSERT_EQ(scene, nullptr);
+        const std::string error = importer.GetErrorString();
+        EXPECT_FALSE(error.empty());
+        EXPECT_NE(error.find(member + "\" was not of type \"" + type + "\" when reading " + context), std::string::npos);
+    }
+}
+
+namespace {
+    /// This class provides a fake schema to the GLTF importer.
+    /// It just checks that the file has a top-level "scene" property which is an integer.
+    class FakeSchemaProvider : public rapidjson::IRemoteSchemaDocumentProvider
+    {
+    public:
+        FakeSchemaProvider(const char* schemaName) :
+            m_schemaName(schemaName)
+        {
+            rapidjson::Document schemaDoc;
+            schemaDoc.Parse(R"==({"properties":{"scene" : { "type" : "integer" }}, "required": [ "scene" ]})==");
+            EXPECT_FALSE(schemaDoc.HasParseError());
+        	m_schema.reset(new rapidjson::SchemaDocument(schemaDoc, m_schemaName.c_str(), static_cast<rapidjson::SizeType>(m_schemaName.size()), this));
+        }
+
+        const rapidjson::SchemaDocument* GetRemoteDocument(const char* uri, rapidjson::SizeType) override {
+            if (m_schemaName == uri) {
+                return m_schema.get();
+            }
+            return nullptr;
+        }
+
+    private:
+        std::string m_schemaName;
+        std::unique_ptr<const rapidjson::SchemaDocument> m_schema;
+    };
+}
+
+TEST_F(utglTF2ImportExport, schemaCheckPass) {
+    FakeSchemaProvider schemaProvider("glTF.schema.json");
+    Assimp::Importer importer;
+    importer.SetPropertyPointer(AI_CONFIG_IMPORT_SCHEMA_DOCUMENT_PROVIDER, &schemaProvider);
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF/BoxTextured.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(scene, nullptr);
+    EXPECT_STREQ(importer.GetErrorString(), "");
+}
+
+TEST_F(utglTF2ImportExport, schemaCheckFail) {
+    FakeSchemaProvider schemaProvider("glTF.schema.json");
+    Assimp::Importer importer;
+    importer.SetPropertyPointer(AI_CONFIG_IMPORT_SCHEMA_DOCUMENT_PROVIDER, &schemaProvider);
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/SchemaFailures/sceneWrongType.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_EQ(scene, nullptr);
+    const std::string errorString = importer.GetErrorString();
+    EXPECT_NE(errorString.find("The JSON document did not satisfy the glTF2 schema"), std::string::npos);
+}
+
+TEST_F(utglTF2ImportExport, noSchemaFound) {
+    // More than one importer might make use the provider, but not all schemas might be present.
+    // Check that the glTF importer handles the case when an non-null provider returns null when asked for schemas.
+    FakeSchemaProvider schemaProvider("missingSchema.json");
+    Assimp::Importer importer;
+    importer.SetPropertyPointer(AI_CONFIG_IMPORT_SCHEMA_DOCUMENT_PROVIDER, &schemaProvider);
+    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF/BoxTextured.gltf", aiProcess_ValidateDataStructure);
+    EXPECT_NE(scene, nullptr);
+    EXPECT_STREQ(importer.GetErrorString(), "");
+}