assimp.assimp/test/unit/utObjImportExport.cpp

/*
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#include "AbstractImportExportBase.h"
#include "SceneDiffer.h"
#include "UnitTestPCH.h"
#include <assimp/postprocess.h>
#include <assimp/scene.h>
#include <assimp/Exporter.hpp>
#include <assimp/Importer.hpp>

using namespace Assimp;

static const float VertComponents[24 * 3] = {
    -0.500000, 0.500000, 0.500000,
    -0.500000, 0.500000, -0.500000,
    -0.500000, -0.500000, -0.500000,
    -0.500000, -0.500000, 0.500000,
    -0.500000, -0.500000, -0.500000,
    0.500000, -0.500000, -0.500000,
    0.500000, -0.500000, 0.500000,
    -0.500000, -0.500000, 0.500000,
    -0.500000, 0.500000, -0.500000,
    0.500000, 0.500000, -0.500000,
    0.500000, -0.500000, -0.500000,
    -0.500000, -0.500000, -0.500000,
    0.500000, 0.500000, 0.500000,
    0.500000, 0.500000, -0.500000,
    -0.500000, 0.500000, -0.500000,
    -0.500000, 0.500000, 0.500000,
    0.500000, -0.500000, 0.500000,
    0.500000, 0.500000, 0.500000,
    -0.500000, 0.500000, 0.500000,
    -0.500000, -0.500000, 0.500000,
    0.500000, -0.500000, -0.500000,
    0.500000, 0.500000, -0.500000,
    0.500000, 0.500000, 0.500000f,
    0.500000, -0.500000, 0.500000f
};

static const char *ObjModel =
        "o 1\n"
        "\n"
        "# Vertex list\n"
        "\n"
        "v -0.5 -0.5  0.5\n"
        "v -0.5 -0.5 -0.5\n"
        "v -0.5  0.5 -0.5\n"
        "v -0.5  0.5  0.5\n"
        "v  0.5 -0.5  0.5\n"
        "v  0.5 -0.5 -0.5\n"
        "v  0.5  0.5 -0.5\n"
        "v  0.5  0.5  0.5\n"
        "\n"
        "# Point / Line / Face list\n"
        "\n"
        "g Box01\n"
        "usemtl Default\n"
        "f 4 3 2 1\n"
        "f 2 6 5 1\n"
        "f 3 7 6 2\n"
        "f 8 7 3 4\n"
        "f 5 8 4 1\n"
        "f 6 7 8 5\n"
        "\n"
        "# End of file\n";

static const char *ObjModel_Issue1111 =
        "o 1\n"
        "\n"
        "# Vertex list\n"
        "\n"
        "v -0.5 -0.5  0.5\n"
        "v -0.5 -0.5 -0.5\n"
        "v -0.5  0.5 -0.5\n"
        "\n"
        "usemtl\n"
        "f 1 2 3\n"
        "\n"
        "# End of file\n";

class utObjImportExport : public AbstractImportExportBase {
protected:
    void SetUp() override {
        m_im = new Assimp::Importer;
    }

    void TearDown() override {
        delete m_im;
        m_im = nullptr;
    }

    aiScene *createScene() {
        aiScene *expScene = new aiScene;
        expScene->mNumMeshes = 1;
        expScene->mMeshes = new aiMesh *[1];
        aiMesh *mesh = new aiMesh;
        mesh->mName.Set("Box01");
        mesh->mNumVertices = 24;
        mesh->mVertices = new aiVector3D[24];
        ::memcpy(&mesh->mVertices->x, &VertComponents[0], sizeof(float) * 24 * 3);
        mesh->mNumFaces = 6;
        mesh->mFaces = new aiFace[mesh->mNumFaces];

        mesh->mFaces[0].mNumIndices = 4;
        mesh->mFaces[0].mIndices = new unsigned int[mesh->mFaces[0].mNumIndices];
        mesh->mFaces[0].mIndices[0] = 0;
        mesh->mFaces[0].mIndices[1] = 1;
        mesh->mFaces[0].mIndices[2] = 2;
        mesh->mFaces[0].mIndices[3] = 3;

        mesh->mFaces[1].mNumIndices = 4;
        mesh->mFaces[1].mIndices = new unsigned int[mesh->mFaces[0].mNumIndices];
        mesh->mFaces[1].mIndices[0] = 4;
        mesh->mFaces[1].mIndices[1] = 5;
        mesh->mFaces[1].mIndices[2] = 6;
        mesh->mFaces[1].mIndices[3] = 7;

        mesh->mFaces[2].mNumIndices = 4;
        mesh->mFaces[2].mIndices = new unsigned int[mesh->mFaces[0].mNumIndices];
        mesh->mFaces[2].mIndices[0] = 8;
        mesh->mFaces[2].mIndices[1] = 9;
        mesh->mFaces[2].mIndices[2] = 10;
        mesh->mFaces[2].mIndices[3] = 11;

        mesh->mFaces[3].mNumIndices = 4;
        mesh->mFaces[3].mIndices = new unsigned int[mesh->mFaces[0].mNumIndices];
        mesh->mFaces[3].mIndices[0] = 12;
        mesh->mFaces[3].mIndices[1] = 13;
        mesh->mFaces[3].mIndices[2] = 14;
        mesh->mFaces[3].mIndices[3] = 15;

        mesh->mFaces[4].mNumIndices = 4;
        mesh->mFaces[4].mIndices = new unsigned int[mesh->mFaces[0].mNumIndices];
        mesh->mFaces[4].mIndices[0] = 16;
        mesh->mFaces[4].mIndices[1] = 17;
        mesh->mFaces[4].mIndices[2] = 18;
        mesh->mFaces[4].mIndices[3] = 19;

        mesh->mFaces[5].mNumIndices = 4;
        mesh->mFaces[5].mIndices = new unsigned int[mesh->mFaces[0].mNumIndices];
        mesh->mFaces[5].mIndices[0] = 20;
        mesh->mFaces[5].mIndices[1] = 21;
        mesh->mFaces[5].mIndices[2] = 22;
        mesh->mFaces[5].mIndices[3] = 23;

        expScene->mMeshes[0] = mesh;

        expScene->mNumMaterials = 1;
        expScene->mMaterials = new aiMaterial *[expScene->mNumMaterials];

        return expScene;
    }

    bool importerTest() override {
        ::Assimp::Importer importer;
        const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/OBJ/spider.obj", aiProcess_ValidateDataStructure);
        return nullptr != scene;
    }

#ifndef ASSIMP_BUILD_NO_EXPORT

    bool exporterTest() override {
        ::Assimp::Importer importer;
        ::Assimp::Exporter exporter;
        const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/OBJ/spider.obj", aiProcess_ValidateDataStructure);
        EXPECT_NE(nullptr, scene);
        EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "obj", ASSIMP_TEST_MODELS_DIR "/OBJ/spider_out.obj"));
        EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "objnomtl", ASSIMP_TEST_MODELS_DIR "/OBJ/spider_nomtl_out.obj"));

        return true;
    }

#endif // ASSIMP_BUILD_NO_EXPORT

protected:
    ::Assimp::Importer *m_im;
    aiScene *m_expectedScene;
};

TEST_F(utObjImportExport, importObjFromFileTest) {
    EXPECT_TRUE(importerTest());
}

#ifndef ASSIMP_BUILD_NO_EXPORT

TEST_F(utObjImportExport, exportObjFromFileTest) {
    EXPECT_TRUE(exporterTest());
}

#endif // ASSIMP_BUILD_NO_EXPORT

TEST_F(utObjImportExport, obj_import_test) {
    const aiScene *scene = m_im->ReadFileFromMemory((void *)ObjModel, strlen(ObjModel), 0);
    aiScene *expected = createScene();
    EXPECT_NE(nullptr, scene);

    SceneDiffer differ;
    EXPECT_TRUE(differ.isEqual(expected, scene));
    differ.showReport();

    m_im->FreeScene();
    for (unsigned int i = 0; i < expected->mNumMeshes; ++i) {
        delete expected->mMeshes[i];
    }
    delete[] expected->mMeshes;
    expected->mMeshes = nullptr;
    delete[] expected->mMaterials;
    expected->mMaterials = nullptr;
    delete expected;
}

TEST_F(utObjImportExport, issue1111_no_mat_name_Test) {
    const aiScene *scene = m_im->ReadFileFromMemory((void *)ObjModel_Issue1111, strlen(ObjModel_Issue1111), 0);
    EXPECT_NE(nullptr, scene);
}

TEST_F(utObjImportExport, issue809_vertex_color_Test) {
    ::Assimp::Importer importer;
    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/OBJ/cube_with_vertexcolors.obj", aiProcess_ValidateDataStructure);
    EXPECT_NE(nullptr, scene);

#ifndef ASSIMP_BUILD_NO_EXPORT
    ::Assimp::Exporter exporter;
    EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "obj", ASSIMP_TEST_MODELS_DIR "/OBJ/test_out.obj"));
#endif // ASSIMP_BUILD_NO_EXPORT
}

TEST_F(utObjImportExport, issue1923_vertex_color_Test) {
    ::Assimp::Importer importer;
    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/OBJ/cube_with_vertexcolors_uni.obj", aiProcess_ValidateDataStructure);
    EXPECT_NE(nullptr, scene);

    scene = importer.GetOrphanedScene();

#ifndef ASSIMP_BUILD_NO_EXPORT
    ::Assimp::Exporter exporter;
    const aiExportDataBlob *blob = exporter.ExportToBlob(scene, "obj");
    EXPECT_NE(nullptr, blob);

    const aiScene *sceneReImport = importer.ReadFileFromMemory(blob->data, blob->size, aiProcess_ValidateDataStructure);
    EXPECT_NE(nullptr, scene);

    SceneDiffer differ;
    EXPECT_TRUE(differ.isEqual(scene, sceneReImport));
#endif // ASSIMP_BUILD_NO_EXPORT

    delete scene;
}

TEST_F(utObjImportExport, only_a_part_of_vertex_colors_Test) {
    ::Assimp::Importer importer;
    const aiScene *const scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/OBJ/only_a_part_of_vertexcolors.obj", aiProcess_ValidateDataStructure);
    EXPECT_NE(nullptr, scene);

    EXPECT_EQ(scene->mNumMeshes, 1U);
    const aiMesh *const mesh = scene->mMeshes[0];
    EXPECT_EQ(mesh->mNumVertices, 9U);
    EXPECT_EQ(mesh->mNumFaces, 3U);
    EXPECT_TRUE(mesh->HasVertexColors(0));

    const aiVector3D *const vertices = mesh->mVertices;
    const aiColor4D *const colors = mesh->mColors[0];
    EXPECT_EQ(aiVector3D(0.0f, 0.0f, 0.0f), vertices[0]);
    EXPECT_EQ(aiColor4D(0.0f, 0.0f, 0.0f, 1.0f), colors[0]);
    EXPECT_EQ(aiVector3D(0.0f, 0.0f, 1.0f), vertices[1]);
    EXPECT_EQ(aiColor4D(0.0f, 0.0f, 1.0f, 1.0f), colors[1]);
    EXPECT_EQ(aiVector3D(0.0f, 1.0f, 0.0f), vertices[2]);
    EXPECT_EQ(aiColor4D(0.0f, 0.0f, 0.0f, 1.0f), colors[2]);
    EXPECT_EQ(aiVector3D(0.0f, 0.0f, 0.0f), vertices[3]);
    EXPECT_EQ(aiColor4D(0.0f, 0.0f, 0.0f, 1.0f), colors[3]);
    EXPECT_EQ(aiVector3D(1.0f, 0.0f, 0.0f), vertices[4]);
    EXPECT_EQ(aiColor4D(1.0f, 0.6f, 0.3f, 1.0f), colors[4]);
    EXPECT_EQ(aiVector3D(0.0f, 1.0f, 0.0f), vertices[5]);
    EXPECT_EQ(aiColor4D(0.0f, 0.0f, 0.0f, 1.0f), colors[5]);
    EXPECT_EQ(aiVector3D(0.0f, 0.0f, 1.0f), vertices[6]);
    EXPECT_EQ(aiColor4D(0.0f, 0.0f, 1.0f, 1.0f), colors[6]);
    EXPECT_EQ(aiVector3D(1.0f, 1.0f, 0.0f), vertices[7]);
    EXPECT_EQ(aiColor4D(0.0f, 0.0f, 0.0f, 1.0f), colors[7]);
    EXPECT_EQ(aiVector3D(1.0f, 0.0f, 0.0f), vertices[8]);
    EXPECT_EQ(aiColor4D(1.0f, 0.6f, 0.3f, 1.0f), colors[8]);

#ifndef ASSIMP_BUILD_NO_EXPORT
    ::Assimp::Exporter exporter;
    EXPECT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "obj", ASSIMP_TEST_MODELS_DIR "/OBJ/test_out.obj"));
#endif // ASSIMP_BUILD_NO_EXPORT
}

TEST_F(utObjImportExport, no_vertex_colors_Test) {
    ::Assimp::Importer importer;
    const aiScene *const scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/OBJ/box.obj", aiProcess_ValidateDataStructure);
    EXPECT_NE(nullptr, scene);

    EXPECT_EQ(scene->mNumMeshes, 1U);
    const aiMesh *const mesh = scene->mMeshes[0];
    EXPECT_FALSE(mesh->HasVertexColors(0));
}

TEST_F(utObjImportExport, issue1453_segfault) {
    static const char *curObjModel =
            "v  0.0  0.0  0.0\n"
            "v  0.0  0.0  1.0\n"
            "v  0.0  1.0  0.0\n"
            "v  0.0  1.0  1.0\n"
            "v  1.0  0.0  0.0\n"
            "v  1.0  0.0  1.0\n"
            "v  1.0  1.0  0.0\n"
            "v  1.0  1.0  1.0\nB";

    Assimp::Importer myimporter;
    const aiScene *scene = myimporter.ReadFileFromMemory(curObjModel, strlen(curObjModel), aiProcess_ValidateDataStructure);
    EXPECT_EQ(nullptr, scene);
}

TEST_F(utObjImportExport, relative_indices_Test) {
    static const char *curObjModel =
            "v -0.500000 0.000000 0.400000\n"
            "v -0.500000 0.000000 -0.800000\n"
            "v -0.500000 1.000000 -0.800000\n"
            "v -0.500000 1.000000 0.400000\n"
            "f -4 -3 -2 -1\nB";

    Assimp::Importer myimporter;
    const aiScene *scene = myimporter.ReadFileFromMemory(curObjModel, strlen(curObjModel), aiProcess_ValidateDataStructure);
    EXPECT_NE(nullptr, scene);

    EXPECT_EQ(scene->mNumMeshes, 1U);
    const aiMesh *mesh = scene->mMeshes[0];
    EXPECT_EQ(mesh->mNumVertices, 4U);
    EXPECT_EQ(mesh->mNumFaces, 1U);
    const aiFace face = mesh->mFaces[0];
    EXPECT_EQ(face.mNumIndices, 4U);
    for (unsigned int i = 0; i < face.mNumIndices; ++i) {
        EXPECT_EQ(face.mIndices[i], i);
    }
}

TEST_F(utObjImportExport, homogeneous_coordinates_Test) {
    static const char *curObjModel =
            "v -0.500000 0.000000 0.400000 0.50000\n"
            "v -0.500000 0.000000 -0.800000 1.00000\n"
            "v 0.500000 1.000000 -0.800000 0.5000\n"
            "f 1 2 3\nB";

    Assimp::Importer myimporter;
    const aiScene *scene = myimporter.ReadFileFromMemory(curObjModel, strlen(curObjModel), aiProcess_ValidateDataStructure);
    EXPECT_NE(nullptr, scene);

    EXPECT_EQ(scene->mNumMeshes, 1U);
    const aiMesh *mesh = scene->mMeshes[0];
    EXPECT_EQ(mesh->mNumVertices, 3U);
    EXPECT_EQ(mesh->mNumFaces, 1U);
    const aiFace face = mesh->mFaces[0];
    EXPECT_EQ(face.mNumIndices, 3U);
    const aiVector3D vertice = mesh->mVertices[0];
    EXPECT_EQ(vertice.x, -1.0f);
    EXPECT_EQ(vertice.y, 0.0f);
    EXPECT_EQ(vertice.z, 0.8f);
}

TEST_F(utObjImportExport, homogeneous_coordinates_divide_by_zero_Test) {
    static const char *curObjModel =
            "v -0.500000 0.000000 0.400000 0.\n"
            "v -0.500000 0.000000 -0.800000 1.00000\n"
            "v 0.500000 1.000000 -0.800000 0.5000\n"
            "f 1 2 3\nB";

    Assimp::Importer myimporter;
    const aiScene *scene = myimporter.ReadFileFromMemory(curObjModel, std::strlen(curObjModel), aiProcess_ValidateDataStructure);
    EXPECT_EQ(nullptr, scene);
}

TEST_F(utObjImportExport, 0based_array_Test) {
    static const char *curObjModel =
            "v -0.500000 0.000000 0.400000\n"
            "v -0.500000 0.000000 -0.800000\n"
            "v -0.500000 1.000000 -0.800000\n"
            "f 0 1 2\nB";

    Assimp::Importer myImporter;
    const aiScene *scene = myImporter.ReadFileFromMemory(curObjModel, strlen(curObjModel), 0);
    EXPECT_EQ(nullptr, scene);
}

TEST_F(utObjImportExport, invalid_normals_uvs) {
    static const char *curObjModel =
            "v -0.500000 0.000000 0.400000\n"
            "v -0.500000 0.000000 -0.800000\n"
            "v -0.500000 1.000000 -0.800000\n"
            "vt 0 0\n"
            "vn 0 1 0\n"
            "f 1/1/1 1/1/1 2/2/2\nB";

    Assimp::Importer myImporter;
    const aiScene *scene = myImporter.ReadFileFromMemory(curObjModel, strlen(curObjModel), 0);
    EXPECT_NE(nullptr, scene);
}

TEST_F(utObjImportExport, no_vt_just_vns) {
    static const char *curObjModel =
            "v 0 0 0\n"
            "v 0 0 0\n"
            "v 0 0 0\n"
            "v 0 0 0\n"
            "v 0 0 0\n"
            "v 0 0 0\n"
            "v 0 0 0\n"
            "v 0 0 0\n"
            "v 0 0 0\n"
            "v 0 0 0\n"
            "v 10 0 0\n"
            "v 0 10 0\n"
            "vn 0 0 1\n"
            "vn 0 0 1\n"
            "vn 0 0 1\n"
            "vn 0 0 1\n"
            "vn 0 0 1\n"
            "vn 0 0 1\n"
            "vn 0 0 1\n"
            "vn 0 0 1\n"
            "vn 0 0 1\n"
            "vn 0 0 1\n"
            "vn 0 0 1\n"
            "vn 0 0 1\n"
            "f 10/10 11/11 12/12\n";

    Assimp::Importer myImporter;
    const aiScene *scene = myImporter.ReadFileFromMemory(curObjModel, strlen(curObjModel), 0);
    EXPECT_NE(nullptr, scene);
}

TEST_F(utObjImportExport, mtllib_after_g) {
    ::Assimp::Importer importer;
    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/OBJ/cube_mtllib_after_g.obj", aiProcess_ValidateDataStructure);
    ASSERT_NE(nullptr, scene);

    EXPECT_EQ(scene->mNumMeshes, 1U);
    const aiMesh *mesh = scene->mMeshes[0];
    const aiMaterial *mat = scene->mMaterials[mesh->mMaterialIndex];
    aiString name;
    ASSERT_EQ(aiReturn_SUCCESS, mat->Get(AI_MATKEY_NAME, name));
    EXPECT_STREQ("MyMaterial", name.C_Str());
}

TEST_F(utObjImportExport, import_point_cloud) {
    ::Assimp::Importer importer;
    const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/OBJ/point_cloud.obj", 0);
    ASSERT_NE(nullptr, scene);
}

TEST_F(utObjImportExport, import_without_linend) {
    Assimp::Importer myImporter;
    const aiScene *scene = myImporter.ReadFile(ASSIMP_TEST_MODELS_DIR "/OBJ/box_without_lineending.obj", 0);
    ASSERT_NE(nullptr, scene);
}

TEST_F(utObjImportExport, import_with_line_continuations) {
    static const char *curObjModel =
            "v -0.5 -0.5 0.5\n"
            "v -0.5 \\\n"
            "  -0.5 -0.5\n"
            "v -0.5 \\\n"
            "   0.5 \\\n"
            "   -0.5\n"
            "f 1 2 3\n";

    Assimp::Importer myImporter;
    const aiScene *scene = myImporter.ReadFileFromMemory(curObjModel, strlen(curObjModel), 0);
    EXPECT_NE(nullptr, scene);

    EXPECT_EQ(scene->mNumMeshes, 1U);
    EXPECT_EQ(scene->mMeshes[0]->mNumVertices, 3U);
    EXPECT_EQ(scene->mMeshes[0]->mNumFaces, 1U);

    auto vertices = scene->mMeshes[0]->mVertices;
    const float threshold = 0.0001f;

    EXPECT_NEAR(vertices[0].x, -0.5f, threshold);
    EXPECT_NEAR(vertices[0].y, -0.5f, threshold);
    EXPECT_NEAR(vertices[0].z, 0.5f, threshold);

    EXPECT_NEAR(vertices[1].x, -0.5f, threshold);
    EXPECT_NEAR(vertices[1].y, -0.5f, threshold);
    EXPECT_NEAR(vertices[1].z, -0.5f, threshold);

    EXPECT_NEAR(vertices[2].x, -0.5f, threshold);
    EXPECT_NEAR(vertices[2].y, 0.5f, threshold);
    EXPECT_NEAR(vertices[2].z, -0.5f, threshold);
}

TEST_F(utObjImportExport, issue2355_mtl_texture_prefix) {
    ::Assimp::Importer importer;
    const aiScene *const scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/OBJ/mtl_different_folder.obj", aiProcess_ValidateDataStructure);
    EXPECT_NE(nullptr, scene);

    EXPECT_EQ(scene->mNumMaterials, 2U);
    const aiMaterial *const material = scene->mMaterials[1];

    aiString texturePath;
    material->GetTexture(aiTextureType_DIFFUSE, 0, &texturePath);
    // The MTL file is in `folder`, the image path should have been prefixed with the folder
    EXPECT_STREQ("folder/image.jpg", texturePath.C_Str());
}