assimp.assimp/test/unit/utglTF2ImportExport.cpp

/*
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#include "AbstractImportExportBase.h"
#include "UnitTestPCH.h"
#include "Tools/TestTools.h"
#include <assimp/commonMetaData.h>
#include <assimp/postprocess.h>
#include <assimp/config.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, bool 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) {
            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);
        } else {
            EXPECT_EQ(aiReturn_FAILURE, material->Get(AI_MATKEY_COLOR_SPECULAR, spec_color));
        }
        if (gloss) {
            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_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, 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, 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 with specular glossiness disabled
    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, false));

    // Export with specular glossiness enabled
    ExportProperties props;
    props.SetPropertyBool(AI_CONFIG_USE_GLTF_PBR_SPECULAR_GLOSSINESS, true);
    EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "glb2", ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF-pbrSpecularGlossiness/BoxTextured_out.glb", 0, &props));

    // And re-import
    EXPECT_TRUE(importerMatTest(ASSIMP_TEST_MODELS_DIR "/glTF2/BoxTextured-glTF-pbrSpecularGlossiness/BoxTextured_out.glb", true, 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, 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].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, 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].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, 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].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, 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 = { { 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, 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, 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]);
    }
}

std::vector<char> ReadFile(const char *name) {
    std::vector<char> ret;

    FILE *p{ nullptr };
    EXPECT_TRUE(Unittest::TestTools::openFilestream(&p, 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);
}

bool checkSkinnedScene(const aiScene *scene){
    float eps = 0.001f;
    bool result = true;
    EXPECT_EQ(scene->mNumMeshes, 1u);
    EXPECT_EQ(scene->mMeshes[0]->mNumBones, 10u);
    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 4u);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[0].x - -1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[0].y - -1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[0].z - 0), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[1].x - 1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[1].y - -1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[1].z - 0), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[2].x - 1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[2].y - 1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[2].z - 0), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[3].x - -1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[3].y - 1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[3].z - 0), eps);

    unsigned int numWeights[] = {4u, 4u, 4u, 4u, 2u , 1u, 1u, 2u, 1u, 1u};
    float weights[10][4] = {{0.207f, 0.291f, 0.057f, 0.303f},
                        {0.113f, 0.243f, 0.499f, 0.251f},
                        {0.005f, 0.010f, 0.041f, 0.093f},
                        {0.090f, 0.234f, 0.404f, 0.243f},
                        {0.090f, 0.222f, 0.000f, 0.000f},
                        {0.216f, 0.000f, 0.000f, 0.000f},
                        {0.058f, 0.000f, 0.000f, 0.000f},
                        {0.086f, 0.000f, 0.000f, 0.111f},
                        {0.088f, 0.000f, 0.000f, 0.000f},
                        {0.049f, 0.000f, 0.000f, 0.000f}};
    for (size_t boneIndex = 0; boneIndex < 10u; ++boneIndex) {
        EXPECT_EQ(scene->mMeshes[0]->mBones[boneIndex]->mNumWeights, numWeights[boneIndex]);
        std::map<unsigned int, float> map;
        for (size_t jointIndex = 0; jointIndex < scene->mMeshes[0]->mBones[boneIndex]->mNumWeights; ++jointIndex){
            auto key = scene->mMeshes[0]->mBones[boneIndex]->mWeights[jointIndex].mVertexId;
            auto weight = scene->mMeshes[0]->mBones[boneIndex]->mWeights[jointIndex].mWeight;
            map[key] = weight;
        }

        for (unsigned int jointIndex = 0; jointIndex < scene->mMeshes[0]->mBones[boneIndex]->mNumWeights; ++jointIndex) {
            auto weight = map[jointIndex];
            EXPECT_LT(abs(ai_real(weight) - ai_real(weights[boneIndex][jointIndex])), 0.002);
        }
    }

    return result;
}

void checkSkinnedSceneLimited(const aiScene *scene){
    float eps = 0.001f;
    EXPECT_EQ(scene->mNumMeshes, 1u);
    EXPECT_EQ(scene->mMeshes[0]->mNumBones, 10u);
    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 4u);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[0].x - -1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[0].y - -1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[0].z - 0), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[1].x - 1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[1].y - -1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[1].z - 0), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[2].x - 1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[2].y - 1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[2].z - 0), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[3].x - -1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[3].y - 1), eps);
    EXPECT_LT(abs(scene->mMeshes[0]->mVertices[3].z - 0), eps);

    unsigned int numWeights[] = {4u, 4u, 1u, 4u, 1u , 1u, 1u, 1u, 1u, 1u};
    float weights[10][4] = {{0.207f, 0.291f, 0.057f, 0.303f},
                            {0.113f, 0.243f, 0.499f, 0.251f},
                            {0.000f, 0.000f, 0.041f, 0.000f},
                            {0.090f, 0.234f, 0.404f, 0.243f},
                            {0.000f, 0.222f, 0.000f, 0.000f},
                            {0.216f, 0.000f, 0.000f, 0.000f},
                            {0.000f, 0.000f, 0.000f, 0.000f},
                            {0.000f, 0.000f, 0.000f, 0.111f},
                            {0.000f, 0.000f, 0.000f, 0.000f},
                            {0.000f, 0.000f, 0.000f, 0.000f}};
    for (unsigned int boneIndex = 0; boneIndex < 10u; ++boneIndex) {
        EXPECT_EQ(scene->mMeshes[0]->mBones[boneIndex]->mNumWeights, numWeights[boneIndex]);
        std::map<unsigned int, float> map;
        for (unsigned int jointIndex = 0; jointIndex < scene->mMeshes[0]->mBones[boneIndex]->mNumWeights; ++jointIndex){
            auto key = scene->mMeshes[0]->mBones[boneIndex]->mWeights[jointIndex].mVertexId;
            auto weight = scene->mMeshes[0]->mBones[boneIndex]->mWeights[jointIndex].mWeight;
            map[key] = weight;
        }
        for (unsigned int jointIndex = 0; jointIndex < scene->mMeshes[0]->mBones[boneIndex]->mNumWeights; ++jointIndex) {
            auto weight = map[jointIndex];
            EXPECT_LT(std::abs(ai_real(weight) - ai_real(weights[boneIndex][jointIndex])), 0.002);
        }
    }
}

TEST_F(utglTF2ImportExport, bug_import_simple_skin2) {
    Assimp::Importer importer;
    Assimp::Exporter exporter;
    const aiScene *scene = importer.ReadFile(
            ASSIMP_TEST_MODELS_DIR "/glTF2/simple_skin/quad_skin.glb",
            aiProcess_ValidateDataStructure);
    checkSkinnedScene(scene);

    ASSERT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "glb2",
            ASSIMP_TEST_MODELS_DIR "/glTF2/simple_skin/quad_four_out.glb"));
    ASSERT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "gltf2",
            ASSIMP_TEST_MODELS_DIR "/glTF2/simple_skin/quad_four_out.gltf"));

    // enable more than four bones per vertex
    Assimp::ExportProperties properties = Assimp::ExportProperties();
    properties.SetPropertyBool(
      AI_CONFIG_EXPORT_GLTF_UNLIMITED_SKINNING_BONES_PER_VERTEX, true);
    ASSERT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "glb2",
            ASSIMP_TEST_MODELS_DIR "/glTF2/simple_skin/quad_all_out.glb", 0u, &properties));
    ASSERT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "gltf2",
            ASSIMP_TEST_MODELS_DIR "/glTF2/simple_skin/quad_all_out.gltf", 0u, &properties));

    // check skinning data of both exported files for limited number bones per vertex
    const aiScene *limitedSceneImported = importer.ReadFile(
            ASSIMP_TEST_MODELS_DIR "/glTF2/simple_skin/quad_four_out.gltf",
            aiProcess_ValidateDataStructure);
    checkSkinnedSceneLimited(limitedSceneImported);
    limitedSceneImported = importer.ReadFile(
            ASSIMP_TEST_MODELS_DIR "/glTF2/simple_skin/quad_four_out.glb",
            aiProcess_ValidateDataStructure);
    checkSkinnedSceneLimited(limitedSceneImported);

    // check skinning data of both exported files for unlimited number bones per vertex
    const aiScene *sceneImported = importer.ReadFile(
            ASSIMP_TEST_MODELS_DIR "/glTF2/simple_skin/quad_all_out.gltf",
            aiProcess_ValidateDataStructure);
    checkSkinnedScene(sceneImported);
    sceneImported = importer.ReadFile(
            ASSIMP_TEST_MODELS_DIR "/glTF2/simple_skin/quad_all_out.glb",
            aiProcess_ValidateDataStructure);
    checkSkinnedScene(sceneImported);


}

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
    const aiScene *robotScene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/glTF2/draco/robot.glb",
        aiProcess_ValidateDataStructure);
#ifndef ASSIMP_ENABLE_DRACO
    // No draco support, scene should not load
    ASSERT_EQ(robotScene, nullptr);
#else
    ASSERT_NE(robotScene, nullptr);
    ASSERT_NE(robotScene->mMetaData, nullptr);
    {
        ASSERT_TRUE(robotScene->mMetaData->HasKey(AI_METADATA_SOURCE_FORMAT));
        aiString format;
        ASSERT_TRUE(robotScene->mMetaData->Get(AI_METADATA_SOURCE_FORMAT, format));
        ASSERT_EQ(strcmp(format.C_Str(), "glTF2 Importer"), 0);
    }
    {
        ASSERT_TRUE(robotScene->mMetaData->HasKey(AI_METADATA_SOURCE_FORMAT_VERSION));
        aiString version;
        ASSERT_TRUE(robotScene->mMetaData->Get(AI_METADATA_SOURCE_FORMAT_VERSION, version));
        ASSERT_EQ(strcmp(version.C_Str(), "2.0"), 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 = {
#ifdef __cpp_lib_constexpr_tuple
    #define TUPLE(x, y, z, w) {x, y, z, w}
#else
    #define TUPLE(x, y, z, w) tup_T(x, y, z, w)
#endif
        TUPLE("/glTF2/wrongTypes/badArray.gltf", "array", "primitives", "meshes[0]"),
        TUPLE("/glTF2/wrongTypes/badString.gltf", "string", "name", "scenes[0]"),
        TUPLE("/glTF2/wrongTypes/badUint.gltf", "uint", "index", "materials[0]"),
        TUPLE("/glTF2/wrongTypes/badNumber.gltf", "number", "scale", "materials[0]"),
        //TUPLE("/glTF2/wrongTypes/badObject.gltf", "object", "pbrMetallicRoughness", "materials[0]"),
        //TUPLE("/glTF2/wrongTypes/badExtension.gltf", "object", "KHR_texture_transform", "materials[0]")
#undef TUPLE
    };
    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);
    }
}

TEST_F(utglTF2ImportExport, wrongObject) {
    // 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 = {
#ifdef __cpp_lib_constexpr_tuple
#define TUPLE(x, y, z, w) \
    { x, y, z, w }
#else
#define TUPLE(x, y, z, w) tup_T(x, y, z, w)
#endif
    TUPLE("/glTF2/wrongTypes/badObject.gltf", "object", "pbrMetallicRoughness", "materials[0]"),
    TUPLE("/glTF2/wrongTypes/badExtension.gltf", "object", "KHR_texture_transform", "materials[0]")
#undef TUPLE
    };
    for (const auto &tuple : wrongTypes) {
        const auto &file = std::get<0>(tuple);
        Assimp::Importer importer;
        const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR + file, aiProcess_ValidateDataStructure);
        ASSERT_NE(scene, nullptr);
    }
}

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(), "");
}

// ------------------------------------------------------------------------------------------------
TEST_F(utglTF2ImportExport, testSetIdentityMatrixEpsilon) {
//    Assimp::Exporter exporter;
    Assimp::ExportProperties properties = Assimp::ExportProperties();
    EXPECT_EQ(AI_CONFIG_CHECK_IDENTITY_MATRIX_EPSILON_DEFAULT,
            properties.GetPropertyFloat("CHECK_IDENTITY_MATRIX_EPSILON",
                    AI_CONFIG_CHECK_IDENTITY_MATRIX_EPSILON_DEFAULT));
    aiMatrix4x4 m;
    m = aiMatrix4x4(1.02f, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1);
    EXPECT_FALSE(m.IsIdentity());
    m = aiMatrix4x4(1.001f, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1);
    EXPECT_TRUE(m.IsIdentity());

    bool b = properties.SetPropertyFloat("CHECK_IDENTITY_MATRIX_EPSILON", 0.0001f);
    EXPECT_TRUE(!b);
    ai_real epsilon = properties.GetPropertyFloat("CHECK_IDENTITY_MATRIX_EPSILON", 0.01f);
    EXPECT_EQ(0.0001f, epsilon);
    m = aiMatrix4x4(1.0002f, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1);
    EXPECT_FALSE(m.IsIdentity(epsilon));
    m = aiMatrix4x4(1.00009f, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1);
    EXPECT_TRUE(m.IsIdentity(epsilon));
}