Remove AppVeyor CI config and badge from README

Co-authored-by: syoyo <18676+syoyo@users.noreply.github.com>

.github/instructions/copilot-instructions.md

@@ -0,0 +1,92 @@
+# Copilot Review Instructions for TinyGLTF
+
+This document provides guidelines for reviewing code changes in the TinyGLTF repository.
+
+## Memory Safety
+
+- **Buffer Overflows**: Check for proper bounds checking when accessing arrays, vectors, and buffers. Verify that buffer sizes are validated before read/write operations.
+- **Null Pointer Dereferences**: Ensure all pointers are checked for null before dereferencing, especially when handling optional glTF fields.
+- **Memory Leaks**: Verify proper resource management, including RAII patterns for file handles, image data, and dynamically allocated memory.
+- **Use-After-Free**: Check for proper lifetime management of objects, especially when dealing with callbacks and asynchronous operations.
+
+## Error Handling
+
+- **File I/O**: Verify that all file operations have proper error checking and meaningful error messages.
+- **JSON Parsing**: Ensure JSON parsing errors are caught and reported with helpful context about the location and nature of the error.
+- **Resource Loading**: Check that failures in loading images, buffers, and other resources are properly handled and don't cause crashes.
+- **Error Propagation**: Verify that errors are properly propagated through the call stack with appropriate error messages.
+
+## glTF 2.0 Specification Compliance
+
+- **Required Fields**: Ensure all required glTF fields are validated and present.
+- **Data Types**: Verify that data types match the glTF specification (e.g., component types, accessor types).
+- **Constraints**: Check that glTF constraints are enforced (e.g., valid ranges for enums, buffer stride requirements).
+- **Extensions**: Verify proper handling of glTF extensions and that unknown extensions are handled gracefully.
+- **Validation**: Ensure new features align with the glTF 2.0 specification from the Khronos Group.
+
+## Cross-Platform Compatibility
+
+- **Windows**: Check for proper handling of Windows-specific issues (path separators, line endings, file operations).
+- **Linux**: Verify compatibility with various Linux distributions and compilers (GCC, Clang).
+- **macOS**: Ensure macOS-specific considerations are addressed (case-sensitive filesystems, Clang compatibility).
+- **Mobile Platforms**: Consider Android and iOS compatibility where applicable.
+- **Endianness**: Verify proper handling of byte order when reading binary data.
+- **Compiler Compatibility**: Ensure code compiles with C++11 standard and supported compilers (MSVC, GCC, Clang).
+
+## Edge Cases in glTF Parsing
+
+- **Empty/Minimal Files**: Verify handling of minimal valid glTF files.
+- **Large Files**: Check for proper handling of large glTF files and buffers without memory exhaustion.
+- **Malformed Data**: Ensure graceful handling of malformed or invalid glTF data.
+- **Missing Optional Fields**: Verify correct behavior when optional glTF fields are absent.
+- **Edge Values**: Check handling of boundary values (e.g., maximum buffer sizes, extreme floating-point values).
+- **Base64 Encoding**: Verify proper handling of base64-encoded data URIs and invalid encodings.
+
+## Backwards Compatibility
+
+- **API Changes**: Ensure public API changes maintain backwards compatibility or are properly deprecated.
+- **Breaking Changes**: Flag any breaking changes for major version updates and document migration paths.
+- **Binary Compatibility**: Consider ABI stability for header-only library changes.
+- **Default Behavior**: Verify that default behavior of existing functionality remains unchanged.
+
+## Performance Considerations
+
+- **Parsing Performance**: Check for unnecessary copies, redundant allocations, and inefficient algorithms in parsing logic.
+- **Memory Usage**: Verify efficient memory usage, especially when loading large glTF files.
+- **I/O Operations**: Ensure efficient file reading and minimize unnecessary disk access.
+- **String Operations**: Check for efficient string handling (use of string_view, move semantics).
+- **STL Usage**: Verify appropriate use of STL containers and algorithms.
+
+## Documentation
+
+- **Public API**: Ensure all public functions, classes, and methods have clear documentation comments.
+- **Parameters**: Verify that function parameters are documented, including expected ranges and constraints.
+- **Return Values**: Document return values and possible error conditions.
+- **Examples**: Check that complex features include usage examples.
+- **Changelog**: Verify that significant changes are documented in release notes or changelog.
+
+## Testing
+
+- **Test Coverage**: Ensure new features include appropriate unit tests or integration tests.
+- **Edge Cases**: Verify that tests cover edge cases and error conditions.
+- **Cross-Platform Tests**: Check that tests run on all supported platforms.
+- **Regression Tests**: Ensure bug fixes include regression tests to prevent recurrence.
+- **Sample Files**: Verify that changes are tested with various valid and invalid glTF sample files.
+
+## Code Style Consistency
+
+- **Header-Only Pattern**: Maintain the header-only library structure.
+- **Naming Conventions**: Follow existing naming conventions (CamelCase for types, snake_case for functions where applicable).
+- **Formatting**: Adhere to the existing code formatting style (check `.clang-format` if available).
+- **Include Guards**: Verify proper include guards and header organization.
+- **Namespace Usage**: Ensure proper use of the `tinygltf` namespace.
+- **Comments**: Maintain consistent comment style with existing code.
+- **C++11 Compliance**: Verify that code uses C++11 features appropriately and doesn't require newer standards unless specified.
+
+## Additional Considerations
+
+- **Third-Party Dependencies**: Minimize new dependencies; prefer existing dependencies (json.hpp, stb_image).
+- **Warnings**: Ensure code compiles without warnings on supported compilers.
+- **const Correctness**: Verify proper use of const for parameters and methods.
+- **RAII**: Prefer RAII patterns for resource management over manual cleanup.
+- **noexcept**: Use noexcept appropriately for move constructors and move assignment operators.

.github/workflows/ci.yml

@@ -0,0 +1,330 @@
+name: Comprehensive CI
+
+on:
+  push:
+    branches:
+      - master
+      - release
+      - devel
+  pull_request:
+    branches:
+      - master
+      - release
+      - devel
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  # Linux x64 - GCC
+  linux-gcc-x64:
+    runs-on: ubuntu-latest
+    name: Linux x64 (GCC)
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Configure
+        run: cmake -B build -DTINYGLTF_BUILD_LOADER_EXAMPLE=ON
+
+      - name: Build
+        run: cmake --build build
+
+      - name: Run loader_example
+        run: ./build/loader_example models/Cube/Cube.gltf
+
+      - name: Run tests
+        run: ctest --test-dir build --output-on-failure
+
+  # Linux x64 - Clang 21
+  linux-clang-x64:
+    runs-on: ubuntu-24.04
+    name: Linux x64 (Clang 21)
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Install Clang 21
+        run: |
+          wget https://apt.llvm.org/llvm.sh
+          chmod +x llvm.sh
+          sudo ./llvm.sh 21
+
+      - name: Configure
+        run: |
+          cmake -B build -DCMAKE_C_COMPILER=clang-21 -DCMAKE_CXX_COMPILER=clang++-21 -DTINYGLTF_BUILD_LOADER_EXAMPLE=ON
+
+      - name: Build
+        run: cmake --build build
+
+      - name: Run loader_example
+        run: |
+          ./build/loader_example models/Cube/Cube.gltf
+
+      - name: Run tests
+        run: ctest --test-dir build --output-on-failure
+
+  # Linux ARM64 - GCC (native)
+  linux-arm64:
+    runs-on: ubuntu-24.04-arm
+    name: Linux ARM64 (GCC)
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Configure
+        run: cmake -B build -DTINYGLTF_BUILD_LOADER_EXAMPLE=ON
+
+      - name: Build
+        run: cmake --build build
+
+      - name: Run loader_example
+        run: ./build/loader_example models/Cube/Cube.gltf
+
+      - name: Run tests
+        run: ctest --test-dir build --output-on-failure
+
+  # macOS ARM64 Apple Silicon
+  macos-arm64:
+    runs-on: macos-14
+    name: macOS ARM64 Apple Silicon (Clang)
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Configure
+        run: cmake -B build -DTINYGLTF_BUILD_LOADER_EXAMPLE=ON
+
+      - name: Build
+        run: cmake --build build
+
+      - name: Run loader_example
+        run: ./build/loader_example models/Cube/Cube.gltf
+
+      - name: Run tests
+        run: ctest --test-dir build --output-on-failure
+
+  # Windows x64 - MSVC
+  windows-msvc-x64:
+    runs-on: windows-latest
+    name: Windows x64 (MSVC)
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Configure
+        run: |
+          mkdir build
+          cd build
+          cmake -G "Visual Studio 17 2022" -A x64 -DTINYGLTF_BUILD_LOADER_EXAMPLE=On -DTINYGLTF_BUILD_GL_EXAMPLES=Off -DTINYGLTF_BUILD_VALIDATOR_EXAMPLE=Off ..
+
+      - name: Build
+        run: cmake --build build --config Release
+
+      - name: Run loader_example
+        run: |
+          .\build\Release\loader_example.exe models\Cube\Cube.gltf
+
+      - name: Run tests
+        run: ctest --test-dir build -C Release --output-on-failure
+
+  # Windows x86 - MSVC
+  windows-msvc-x86:
+    runs-on: windows-latest
+    name: Windows x86 (MSVC)
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Configure
+        run: |
+          mkdir build
+          cd build
+          cmake -G "Visual Studio 17 2022" -A Win32 -DTINYGLTF_BUILD_LOADER_EXAMPLE=On -DTINYGLTF_BUILD_GL_EXAMPLES=Off -DTINYGLTF_BUILD_VALIDATOR_EXAMPLE=Off ..
+
+      - name: Build
+        run: cmake --build build --config Release
+
+      - name: Run tests
+        run: ctest --test-dir build -C Release --output-on-failure
+
+  # Windows ARM64 - MSVC (cross-compile)
+  windows-msvc-arm64:
+    runs-on: windows-latest
+    name: Windows ARM64 (MSVC) - Cross-compile
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Configure
+        run: |
+          mkdir build
+          cd build
+          cmake -G "Visual Studio 17 2022" -A ARM64 -DTINYGLTF_BUILD_LOADER_EXAMPLE=On -DTINYGLTF_BUILD_GL_EXAMPLES=Off -DTINYGLTF_BUILD_VALIDATOR_EXAMPLE=Off ..
+
+      - name: Build
+        run: cmake --build build --config Release
+
+  # Windows MinGW - MSYS2
+  windows-mingw-msys2:
+    runs-on: windows-latest
+    name: Windows x64 (MinGW MSYS2)
+    defaults:
+      run:
+        shell: msys2 {0}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup MSYS2
+        uses: msys2/setup-msys2@v2
+        with:
+          msystem: UCRT64
+          install: base-devel
+          pacboy: >-
+            cc:p cmake:p ninja:p
+          update: true
+          release: false
+
+      - name: Build with CMake
+        run: |
+          cmake -G"Ninja" -S . -B build
+          cmake --build build
+
+      - name: Run loader_example
+        run: |
+          ./build/loader_example models/Cube/Cube.gltf
+
+      - name: Run tests
+        run: ctest --test-dir build --output-on-failure
+
+  # Linux -> Windows MinGW Cross-compile
+  linux-mingw-cross:
+    runs-on: ubuntu-latest
+    name: Linux→Windows (MinGW Cross) - Build Only
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Install MinGW
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y build-essential mingw-w64
+
+      - name: Build
+        run: |
+          x86_64-w64-mingw32-g++ -std=c++11 -o loader_example.exe loader_example.cc
+
+  # Special Configuration: No Exceptions
+  linux-noexception:
+    runs-on: ubuntu-latest
+    name: Linux x64 (GCC) - No Exceptions
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Build loader_example
+        run: |
+          g++ -DTINYGLTF_NOEXCEPTION -std=c++11 -o loader_example loader_example.cc
+
+      - name: Run loader_example
+        run: |
+          ./loader_example models/Cube/Cube.gltf
+
+      - name: Build and run unit tests
+        run: |
+          cd tests
+          g++ -DTINYGLTF_NOEXCEPTION -I../ -std=c++11 -g -O0 -o tester_noexcept tester.cc
+          ./tester_noexcept
+
+  # Special Configuration: Header-Only Mode
+  linux-header-only:
+    runs-on: ubuntu-latest
+    name: Linux x64 (GCC) - Header-Only Mode
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Build with CMake Header-Only
+        run: |
+          mkdir build
+          cmake -B build -DTINYGLTF_HEADER_ONLY=ON -DTINYGLTF_BUILD_LOADER_EXAMPLE=ON
+          cmake --build build
+
+      - name: Run loader_example
+        run: |
+          ./build/loader_example models/Cube/Cube.gltf
+
+      - name: Run tests
+        run: ctest --test-dir build --output-on-failure
+
+  # Special Configuration: RapidJSON Backend
+  linux-rapidjson:
+    runs-on: ubuntu-latest
+    name: Linux x64 (GCC) - RapidJSON Backend
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Clone RapidJSON
+        run: |
+          git clone https://github.com/Tencent/rapidjson
+
+      - name: Configure
+        run: |
+          cmake -B build -DTINYGLTF_USE_RAPIDJSON=ON -DTINYGLTF_BUILD_LOADER_EXAMPLE=ON -DCMAKE_PREFIX_PATH=$PWD/rapidjson
+
+      - name: Build
+        run: cmake --build build
+
+      - name: Run loader_example
+        run: |
+          ./build/loader_example models/Cube/Cube.gltf
+
+      - name: Run tests
+        run: ctest --test-dir build --output-on-failure
+
+  # Special Configuration: AddressSanitizer
+  linux-asan:
+    runs-on: ubuntu-latest
+    name: Linux x64 (Clang) - AddressSanitizer
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Build loader_example with ASan
+        run: |
+          clang++ -fsanitize=address -std=c++11 -g -O1 -o loader_example loader_example.cc
+
+      - name: Run loader_example
+        run: |
+          ./loader_example models/Cube/Cube.gltf
+
+      - name: Build and run unit tests with ASan
+        run: |
+          cd tests
+          clang++ -fsanitize=address -I../ -std=c++11 -g -O1 -o tester tester.cc
+          ./tester
+
+  # Special Configuration: UndefinedBehaviorSanitizer
+  linux-ubsan:
+    runs-on: ubuntu-latest
+    name: Linux x64 (Clang) - UndefinedBehaviorSanitizer
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Build loader_example with UBSan
+        run: |
+          clang++ -fsanitize=undefined -std=c++11 -g -O1 -o loader_example loader_example.cc
+
+      - name: Run loader_example
+        run: |
+          ./loader_example models/Cube/Cube.gltf
+
+      - name: Build and run unit tests with UBSan
+        run: |
+          cd tests
+          clang++ -fsanitize=undefined -I../ -std=c++11 -g -O1 -o tester tester.cc
+          ./tester

CMakeLists.txt

@@ -14,6 +14,7 @@ option(TINYGLTF_BUILD_LOADER_EXAMPLE "Build loader_example(load glTF and dump in
 option(TINYGLTF_BUILD_GL_EXAMPLES "Build GL exampels(requires glfw, OpenGL, etc)" OFF)
 option(TINYGLTF_BUILD_VALIDATOR_EXAMPLE "Build validator exampe" OFF)
 option(TINYGLTF_BUILD_BUILDER_EXAMPLE "Build glTF builder example" OFF)
+option(TINYGLTF_BUILD_TESTS "Build unit tests" OFF)
 option(TINYGLTF_HEADER_ONLY "On: header-only mode. Off: create tinygltf library(No TINYGLTF_IMPLEMENTATION required in your project)" OFF)
 option(TINYGLTF_INSTALL "Install tinygltf files during install step. Usually set to OFF if you include tinygltf through add_subdirectory()" ON)
 option(TINYGLTF_INSTALL_VENDOR "Install vendored nlohmann/json and nothings/stb headers" ON)
@@ -37,6 +38,16 @@ if (TINYGLTF_BUILD_BUILDER_EXAMPLE)
   add_subdirectory ( examples/build-gltf )
 endif (TINYGLTF_BUILD_BUILDER_EXAMPLE)
 
+if (TINYGLTF_BUILD_TESTS)
+  enable_testing()
+  add_executable(tester tests/tester.cc)
+  target_include_directories(tester PRIVATE
+    ${CMAKE_CURRENT_SOURCE_DIR}
+    ${CMAKE_CURRENT_SOURCE_DIR}/tests
+  )
+  add_test(NAME tester COMMAND tester WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/tests)
+endif (TINYGLTF_BUILD_TESTS)
+
 #
 # for add_subdirectory and standalone build
 #

README.md

@@ -26,8 +26,6 @@ Currently TinyGLTF is stable and maintenance mode. No drastic changes and featur
 
 ## Builds
 
-[![Build status](https://ci.appveyor.com/api/projects/status/warngenu9wjjhlm8?svg=true)](https://ci.appveyor.com/project/syoyo/tinygltf)
-
 ![C/C++ CI](https://github.com/syoyo/tinygltf/workflows/C/C++%20CI/badge.svg)
 
 ## Features
@@ -159,9 +157,10 @@ Model model;
 TinyGLTF loader;
 std::string err;
 std::string warn;
+std::string filename = "input.gltf";
 
-bool ret = loader.LoadASCIIFromFile(&model, &err, &warn, argv[1]);
-//bool ret = loader.LoadBinaryFromFile(&model, &err, &warn, argv[1]); // for binary glTF(.glb)
+bool ret = loader.LoadASCIIFromFile(&model, &err, &warn, filename);
+//bool ret = loader.LoadBinaryFromFile(&model, &err, &warn, filename); // for binary glTF(.glb)
 
 if (!warn.empty()) {
   printf("Warn: %s\n", warn.c_str());
@@ -172,8 +171,7 @@ if (!err.empty()) {
 }
 
 if (!ret) {
-  printf("Failed to parse glTF\n");
-  return -1;
+  printf("Failed to parse glTF: %s\n", filename.c_str());
 }
 ```
 
@@ -194,7 +192,6 @@ if (!ret) {
 * `TINYGLTF_NO_INCLUDE_STB_IMAGE `: Disable including `stb_image.h` from within `tiny_gltf.h` because it has been already included before or you want to include it using custom path before including `tiny_gltf.h`.
 * `TINYGLTF_NO_INCLUDE_STB_IMAGE_WRITE `: Disable including `stb_image_write.h` from within `tiny_gltf.h` because it has been already included before or you want to include it using custom path before including `tiny_gltf.h`.
 * `TINYGLTF_USE_RAPIDJSON` : Use RapidJSON as a JSON parser/serializer. RapidJSON files are not included in TinyGLTF repo. Please set an include path to RapidJSON if you enable this feature.
-* `TINYGLTF_USE_CPP14` : Use C++14 feature(requires C++14 compiler). This may give better performance than C++11.
 
 
 ## CMake options

appveyor.yml

@@ -1,18 +0,0 @@
-version: 0.9.{build}
-
-image:
-  - Visual Studio 2015
-
-# scripts that runs after repo cloning.
-install:
-  - vcsetup.bat
-
-platform: x64
-configuration: Release
-
-build:
-  parallel: true
-  project: TinyGLTFSolution.sln
-
-after_build:
-  - examples.bat

tests/tester.cc

@@ -1121,8 +1121,10 @@ TEST_CASE("images-as-is", "[issue-487]") {
     // All the images should have been written to disk with their original data
     for (const auto& image : model.images)  {
       // Make sure the image files exist
-      std::fstream file(image.uri);
-      CHECK(file.good());
+      {
+        std::fstream file(image.uri);
+        CHECK(file.good());
+      } // Close file before stbi_load (Windows sharing violation fix)
 #ifndef TINYGLTF_NO_STB_IMAGE
       // Make sure we can load the images
       int w = -1, h = -1, component = -1;

tiny_gltf.h

@@ -50,12 +50,6 @@
 #include <utility>
 #include <vector>
 
-// Auto-detect C++14 standard version
-#if !defined(TINYGLTF_USE_CPP14) && defined(__cplusplus) && \
-    (__cplusplus >= 201402L)
-#define TINYGLTF_USE_CPP14
-#endif
-
 #ifdef __ANDROID__
 #ifdef TINYGLTF_ANDROID_LOAD_FROM_ASSETS
 #include <android/asset_manager.h>
@@ -834,20 +828,20 @@ struct Accessor {
       maxValues;  // optional. integer value is promoted to double
 
   struct Sparse {
-    int count;
-    bool isSparse;
+    int count{0};
+    bool isSparse{false};
     struct {
-      size_t byteOffset;
-      int bufferView;
-      int componentType;  // a TINYGLTF_COMPONENT_TYPE_ value
+      size_t byteOffset{0};
+      int bufferView{-1};
+      int componentType{-1};  // a TINYGLTF_COMPONENT_TYPE_ value
       Value extras;
       ExtensionMap extensions;
       std::string extras_json_string;
       std::string extensions_json_string;
     } indices;
     struct {
-      int bufferView;
-      size_t byteOffset;
+      int bufferView{-1};
+      size_t byteOffset{0};
       Value extras;
       ExtensionMap extensions;
       std::string extras_json_string;
@@ -898,11 +892,7 @@ struct Accessor {
     // unreachable return 0;
   }
 
-  Accessor()
-
-  {
-    sparse.isSparse = false;
-  }
+  Accessor() = default;
   DEFAULT_METHODS(Accessor)
   bool operator==(const tinygltf::Accessor &) const;
 };
@@ -2461,9 +2451,8 @@ inline unsigned char from_hex(unsigned char ch) {
 }
 
 static const std::string urldecode(const std::string &str) {
-  using namespace std;
-  string result;
-  string::size_type i;
+  std::string result;
+  std::string::size_type i;
   for (i = 0; i < str.size(); ++i) {
     if (str[i] == '+') {
       result += ' ';
@@ -4362,7 +4351,7 @@ static bool ParseImage(Image *image, const int image_idx, std::string *err,
     // Just only save some information here. Loading actual image data from
     // bufferView is done after this `ParseImage` function.
     image->bufferView = bufferView;
-    image->mimeType = mime_type;
+    image->mimeType = std::move( mime_type );
     image->width = width;
     image->height = height;
 
@@ -5261,7 +5250,7 @@ static bool ParseNode(Node *node, std::string *err, const detail::json &o,
   if (node->extensions.count("MSFT_lod") != 0) {
     auto const &msft_lod_ext = node->extensions["MSFT_lod"];
     if (msft_lod_ext.Has("ids")) {
-      auto idsArr = msft_lod_ext.Get("ids");
+      const auto &idsArr = msft_lod_ext.Get("ids");
       for (size_t i = 0; i < idsArr.ArrayLen(); ++i) {
         node->lods.emplace_back(idsArr.Get(i).GetNumberAsInt());
       }
@@ -5290,7 +5279,7 @@ static bool ParseScene(Scene *scene, std::string *err, const detail::json &o,
   if (scene->extensions.count("KHR_audio") != 0) {
     auto const &audio_ext = scene->extensions["KHR_audio"];
     if (audio_ext.Has("emitters")) {
-      auto emittersArr = audio_ext.Get("emitters");
+      const auto &emittersArr = audio_ext.Get("emitters");
       for (size_t i = 0; i < emittersArr.ArrayLen(); ++i) {
         scene->audioEmitters.emplace_back(emittersArr.Get(i).GetNumberAsInt());
       }
@@ -5326,7 +5315,7 @@ static bool ParsePbrMetallicRoughness(
       }
       return false;
     }
-    pbr->baseColorFactor = baseColorFactor;
+    pbr->baseColorFactor = std::move( baseColorFactor );
   }
 
   {
@@ -5478,7 +5467,7 @@ static bool ParseMaterial(Material *material, std::string *err, std::string *war
   if (material->extensions.count("MSFT_lod") != 0) {
     auto const &msft_lod_ext = material->extensions["MSFT_lod"];
     if (msft_lod_ext.Has("ids")) {
-      auto idsArr = msft_lod_ext.Get("ids");
+      const auto &idsArr = msft_lod_ext.Get("ids");
       for (size_t i = 0; i < idsArr.ArrayLen(); ++i) {
         material->lods.emplace_back(idsArr.Get(i).GetNumberAsInt());
       }