Merge branch 'release' of github.com:syoyo/tinygltf into release

allow serializing a const Model

.github/FUNDING.yml

@@ -0,0 +1,13 @@
+# These are supported funding model platforms
+
+github: syoyo
+#patreon: # Replace with a single Patreon username
+#open_collective: # Replace with a single Open Collective username
+#ko_fi: # Replace with a single Ko-fi username
+#tidelift: # Replace with a single Tidelift platform-name/package-name e.g., npm/babel
+#community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
+#liberapay: # Replace with a single Liberapay username
+#issuehunt: # Replace with a single IssueHunt username
+#otechie: # Replace with a single Otechie username
+#lfx_crowdfunding: # Replace with a single LFX Crowdfunding project-name e.g., cloud-foundry
+#custom: # Replace with up to 4 custom sponsorship URLs e.g., ['link1', 'link2']

.github/workflows/codeql-analysis.yml

@@ -0,0 +1,72 @@
+# For most projects, this workflow file will not need changing; you simply need
+# to commit it to your repository.
+#
+# You may wish to alter this file to override the set of languages analyzed,
+# or to provide custom queries or build logic.
+#
+# ******** NOTE ********
+# We have attempted to detect the languages in your repository. Please check
+# the `language` matrix defined below to confirm you have the correct set of
+# supported CodeQL languages.
+#
+name: "CodeQL"
+
+on:
+  push:
+    branches: [ "master" ]
+  pull_request:
+    # The branches below must be a subset of the branches above
+    branches: [ "master" ]
+  schedule:
+    - cron: '21 20 * * 5'
+
+jobs:
+  analyze:
+    name: Analyze
+    runs-on: ubuntu-latest
+    permissions:
+      actions: read
+      contents: read
+      security-events: write
+
+    strategy:
+      fail-fast: false
+      matrix:
+        language: [ 'cpp', 'python' ]
+        # CodeQL supports [ 'cpp', 'csharp', 'go', 'java', 'javascript', 'python', 'ruby' ]
+        # Learn more about CodeQL language support at https://aka.ms/codeql-docs/language-support
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v3
+
+    # Initializes the CodeQL tools for scanning.
+    - name: Initialize CodeQL
+      uses: github/codeql-action/init@v2
+      with:
+        languages: ${{ matrix.language }}
+        # If you wish to specify custom queries, you can do so here or in a config file.
+        # By default, queries listed here will override any specified in a config file.
+        # Prefix the list here with "+" to use these queries and those in the config file.
+        
+        # Details on CodeQL's query packs refer to : https://docs.github.com/en/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/configuring-code-scanning#using-queries-in-ql-packs
+        # queries: security-extended,security-and-quality
+
+        
+    # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
+    # If this step fails, then you should remove it and run the build manually (see below)
+    - name: Autobuild
+      uses: github/codeql-action/autobuild@v2
+
+    # ℹ️ Command-line programs to run using the OS shell.
+    # 📚 See https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsrun
+
+    #   If the Autobuild fails above, remove it and uncomment the following three lines. 
+    #   modify them (or add more) to build your code if your project, please refer to the EXAMPLE below for guidance.
+
+    # - run: |
+    #   echo "Run, Build Application using script"
+    #   ./location_of_script_within_repo/buildscript.sh
+
+    - name: Perform CodeQL Analysis
+      uses: github/codeql-action/analyze@v2

.gitignore

@@ -68,4 +68,11 @@ loader_example
 tests/tester
 tests/tester_noexcept
 tests/issue-97.gltf
+tests/issue-261.gltf
 
+# unignore
+!Makefile
+!examples/build-gltf/Makefile
+!examples/raytrace/cornellbox_suzanne.obj
+!tests/Makefile
+!tools/windows/premake5.exe

CMakeLists.txt

@@ -2,6 +2,9 @@ cmake_minimum_required(VERSION 3.6)
 
 PROJECT (tinygltf)
 
+include(GNUInstallDirs)
+include(CMakePackageConfigHelpers)
+
 SET(CMAKE_CXX_STANDARD 11)
 
 option(TINYGLTF_BUILD_LOADER_EXAMPLE "Build loader_example(load glTF and dump infos)" ON)
@@ -54,7 +57,10 @@ else (TINYGLTF_HEADER_ONLY)
 endif (TINYGLTF_HEADER_ONLY)
 
 if (TINYGLTF_INSTALL)
-
+  install(TARGETS tinygltf EXPORT tinygltfTargets)
+  install(EXPORT tinygltfTargets NAMESPACE tinygltf:: FILE TinyGLTFTargets.cmake DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake)
+  configure_package_config_file(${CMAKE_CURRENT_SOURCE_DIR}/cmake/TinyGLTFConfig.cmake.in ${CMAKE_CURRENT_BINARY_DIR}/TinyGLTFConfig.cmake INSTALL_DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake)
+  install(FILES ${CMAKE_CURRENT_BINARY_DIR}/TinyGLTFConfig.cmake DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake)
   # Do not install .lib even if !TINYGLTF_HEADER_ONLY
 
   INSTALL ( FILES
@@ -67,10 +73,4 @@ if (TINYGLTF_INSTALL)
     include
     )
 
-  INSTALL ( FILES
-    cmake/TinyGLTFConfig.cmake
-    DESTINATION
-    cmake
-    )
-
 endif(TINYGLTF_INSTALL)

README.md

@@ -86,6 +86,12 @@ In extension(`ExtensionMap`), JSON number value is parsed as int or float(number
 * [basic](examples/basic) : Basic glTF viewer with texturing support.
 * [build-gltf](examples/build-gltf) : Build simple glTF scene from a scratch.
 
+### WASI/WASM build
+
+Users who want to run TinyGLTF securely and safely(e.g. need to handle malcious glTF file to serve online glTF conver),
+I recommend to build TinyGLTF for WASM target.
+WASI build example is located in [wasm](wasm) .
+
 ## Projects using TinyGLTF
 
 * px_render Single header C++ Libraries for Thread Scheduling, Rendering, and so on... https://github.com/pplux/px
@@ -100,6 +106,7 @@ In extension(`ExtensionMap`), JSON number value is parsed as int or float(number
 * [TDME2](https://github.com/andreasdr/tdme2) - TDME2 - ThreeDeeMiniEngine2 is a lightweight 3D engine including tools suited for 3D game development using C++11
 * [SanityEngine](https://github.com/DethRaid/SanityEngine) - A C++/D3D12 renderer focused on the personal and proessional development of its developer
 * [Open3D](http://www.open3d.org/) - A Modern Library for 3D Data Processing
+* [Supernova Engine](https://github.com/supernovaengine/supernova) - Game engine for 2D and 3D projects with Lua or C++ in data oriented design.
 * Your projects here! (Please send PR)
 
 ## TODOs
@@ -222,7 +229,7 @@ add_subdirectory(/path/to/tinygltf)
 
 #### Setup
 
-Python 2.6 or 2.7 required.
+Python required.
 Git clone https://github.com/KhronosGroup/glTF-Sample-Models to your local dir.
 
 #### Run parsing test

cmake/TinyGLTFConfig.cmake

@@ -1,15 +0,0 @@
-# -*- cmake -*-
-# - Find TinyGLTF
-
-# TinyGLTF_INCLUDE_DIR      TinyGLTF's include directory
-
-
-FIND_PACKAGE ( PackageHandleStandardArgs )
-
-SET ( TinyGLTF_INCLUDE_DIR "${TinyGLTF_DIR}/../include" CACHE STRING "TinyGLTF include directory")
-
-FIND_FILE ( TinyGLTF_HEADER tiny_gltf.h PATHS ${TinyGLTF_INCLUDE_DIR} )
-
-IF (NOT TinyGLTF_HEADER)
-  MESSAGE ( FATAL_ERROR "Unable to find tiny_gltf.h, TinyGLTF_INCLUDE_DIR = ${TinyGLTF_INCLUDE_DIR}")
-ENDIF ()

cmake/TinyGLTFConfig.cmake.in

@@ -0,0 +1,3 @@
+@PACKAGE_INIT@
+
+include(${CMAKE_CURRENT_LIST_DIR}/TinyGLTFTargets.cmake)

test_runner.py

@@ -1,7 +1,5 @@
 #!/usr/bin/env python
 
-# Assume python 2.6 or 2.7
-
 import glob
 import os
 import subprocess

tests/tester.cc

@@ -482,3 +482,124 @@ TEST_CASE("expandpath-utf-8", "[pr-226]") {
 
 }
 #endif
+
+TEST_CASE("empty-bin-buffer", "[issue-382]") {
+  tinygltf::Model model;
+  tinygltf::TinyGLTF ctx;
+  std::string err;
+  std::string warn;
+
+  tinygltf::Model model_empty;
+  std::stringstream stream;
+  bool ret = ctx.WriteGltfSceneToStream(&model_empty, stream, false, true);
+  REQUIRE(ret == true);
+  std::string str = stream.str();
+  const unsigned char* bytes = (unsigned char*)str.data();
+  ret = ctx.LoadBinaryFromMemory(&model, &err, &warn, bytes, str.size());
+  if (!err.empty()) {
+    std::cerr << err << std::endl;
+  }
+  REQUIRE(true == ret);
+
+  err.clear();
+  warn.clear();
+
+  tinygltf::Model model_empty_buffer;
+  model_empty_buffer.buffers.push_back(tinygltf::Buffer());
+  stream = std::stringstream();
+  ret = ctx.WriteGltfSceneToStream(&model_empty_buffer, stream, false, true);
+  REQUIRE(ret == true);
+  str = stream.str();
+  bytes = (unsigned char*)str.data();
+  ret = ctx.LoadBinaryFromMemory(&model, &err, &warn, bytes, str.size());
+  if (err.empty()) {
+    std::cerr << "there should have been an error reported" << std::endl;
+  }
+  REQUIRE(false == ret);
+
+  err.clear();
+  warn.clear();
+
+  tinygltf::Model model_single_byte_buffer;
+  tinygltf::Buffer buffer;
+  buffer.data.push_back(0);
+  model_single_byte_buffer.buffers.push_back(buffer);
+  stream = std::stringstream();
+  ret = ctx.WriteGltfSceneToStream(&model_single_byte_buffer, stream, false, true);
+  REQUIRE(ret == true);
+  str = stream.str();
+  {
+    std::ofstream ofs("tmp.glb");
+    ofs.write(str.data(), str.size());
+  }
+
+  bytes = (unsigned char*)str.data();
+  ret = ctx.LoadBinaryFromMemory(&model_single_byte_buffer, &err, &warn, bytes, str.size());
+  if (!err.empty()) {
+    std::cerr << err << std::endl;
+  }
+  REQUIRE(true == ret);
+}
+
+TEST_CASE("serialize-const-image", "[issue-394]") {
+  tinygltf::Model m;
+  tinygltf::Image i;
+  i.width = 1;
+  i.height = 1;
+  i.component = 4;
+  i.bits = 8;
+  i.pixel_type = TINYGLTF_COMPONENT_TYPE_UNSIGNED_BYTE;
+  i.image = {255, 255, 255, 255};
+  i.uri = "image.png";
+  m.images.push_back(i);
+
+  std::stringstream os;
+
+  tinygltf::TinyGLTF ctx;
+  ctx.WriteGltfSceneToStream(const_cast<const tinygltf::Model *>(&m), os, false,
+                             false);
+  REQUIRE(m.images[0].uri == i.uri);
+
+  // use nlohmann json
+  nlohmann::json j = nlohmann::json::parse(os.str());
+
+  REQUIRE(1 == j["images"].size());
+  REQUIRE(j["images"][0].is_object());
+  REQUIRE(j["images"][0]["uri"].get<std::string>() != i.uri);
+  REQUIRE(j["images"][0]["uri"].get<std::string>().rfind("data:", 0) == 0);
+}
+
+TEST_CASE("serialize-image-callback", "[issue-394]") {
+  tinygltf::Model m;
+  tinygltf::Image i;
+  i.width = 1;
+  i.height = 1;
+  i.bits = 32;
+  i.image = {255, 255, 255, 255};
+  i.uri = "foo";
+  m.images.push_back(i);
+
+  std::stringstream os;
+
+  auto writer = [](const std::string *basepath, const std::string *filename,
+                   const tinygltf::Image *image, bool embedImages,
+                   std::string *out_uri, void *user_pointer) -> bool {
+    REQUIRE(*filename == "foo");
+    REQUIRE(embedImages == true);
+    REQUIRE(user_pointer == (void *)0xba5e1e55);
+    *out_uri = "bar";
+    return true;
+  };
+
+  tinygltf::TinyGLTF ctx;
+  ctx.SetImageWriter(writer, (void *)0xba5e1e55);
+  ctx.WriteGltfSceneToStream(const_cast<const tinygltf::Model *>(&m), os, false,
+                             false);
+
+  // use nlohmann json
+  nlohmann::json j = nlohmann::json::parse(os.str());
+
+  REQUIRE(1 == j["images"].size());
+  REQUIRE(j["images"][0].is_object());
+  REQUIRE(j["images"][0]["uri"].get<std::string>() == "bar");
+}

tiny_gltf.h

@@ -26,10 +26,14 @@
 // THE SOFTWARE.
 
 // Version:
+//  - v2.7.0 Change WriteImageDataFunction user callback function signature. PR#393.
+//  - v2.6.3 Fix GLB file with empty BIN chunk was not handled. PR#382 and PR#383.
+//  - v2.6.2 Fix out-of-bounds access of accessors. PR#379.
+//  - v2.6.1 Better GLB validation check when loading.
 //  - v2.6.0 Support serializing sparse accessor(Thanks to @fynv).
 //           Disable expanding file path for security(no use of awkward `wordexp` anymore).
 //  - v2.5.0 Add SetPreserveImageChannels() option to load image data as is.
-//  - v2.4.3 Fix null object output when when material has all default
+//  - v2.4.3 Fix null object output when material has all default
 //  parameters.
 //  - v2.4.2 Decode percent-encoded URI.
 //  - v2.4.1 Fix some glTF object class does not have `extensions` and/or
@@ -43,7 +47,7 @@
 //  - v2.2.0 Add loading 16bit PNG support. Add Sparse accessor support(Thanks
 //  to @Ybalrid)
 //  - v2.1.0 Add draco compression.
-//  - v2.0.1 Add comparsion feature(Thanks to @Selmar).
+//  - v2.0.1 Add comparison feature(Thanks to @Selmar).
 //  - v2.0.0 glTF 2.0!.
 //
 // Tiny glTF loader is using following third party libraries:
@@ -66,6 +70,11 @@
 #include <string>
 #include <vector>
 
+//Auto-detect C++14 standard version
+#if !defined(TINYGLTF_USE_CPP14) && defined(__cplusplus) && (__cplusplus >= 201402L)
+#define TINYGLTF_USE_CPP14
+#endif
+
 #ifndef TINYGLTF_USE_CPP14
 #include <functional>
 #endif
@@ -192,7 +201,11 @@ namespace tinygltf {
 
 #ifdef __ANDROID__
 #ifdef TINYGLTF_ANDROID_LOAD_FROM_ASSETS
+#ifdef TINYGLTF_IMPLEMENTATION
 AAssetManager *asset_manager = nullptr;
+#else
+extern AAssetManager *asset_manager;
+#endif
 #endif
 #endif
 
@@ -225,7 +238,7 @@ static inline int32_t GetComponentSizeInBytes(uint32_t componentType) {
   } else if (componentType == TINYGLTF_COMPONENT_TYPE_DOUBLE) {
     return 8;
   } else {
-    // Unknown componenty type
+    // Unknown component type
     return -1;
   }
 }
@@ -246,7 +259,7 @@ static inline int32_t GetNumComponentsInType(uint32_t ty) {
   } else if (ty == TINYGLTF_TYPE_MAT4) {
     return 16;
   } else {
-    // Unknown componenty type
+    // Unknown component type
     return -1;
   }
 }
@@ -433,7 +446,7 @@ TINYGLTF_VALUE_GET(Value::Object, object_value_)
 #pragma clang diagnostic ignored "-Wpadded"
 #endif
 
-/// Agregate object for representing a color
+/// Aggregate object for representing a color
 using ColorValue = std::array<double, 4>;
 
 // === legacy interface ====
@@ -470,7 +483,7 @@ struct Parameter {
     if (it != std::end(json_double_value)) {
       return int(it->second);
     }
-    // As per the spec, if texCoord is ommited, this parameter is 0
+    // As per the spec, if texCoord is omitted, this parameter is 0
     return 0;
   }
 
@@ -482,7 +495,7 @@ struct Parameter {
     if (it != std::end(json_double_value)) {
       return it->second;
     }
-    // As per the spec, if scale is ommited, this paramter is 1
+    // As per the spec, if scale is omitted, this parameter is 1
     return 1;
   }
 
@@ -494,7 +507,7 @@ struct Parameter {
     if (it != std::end(json_double_value)) {
       return it->second;
     }
-    // As per the spec, if strenghth is ommited, this parameter is 1
+    // As per the spec, if strength is omitted, this parameter is 1
     return 1;
   }
 
@@ -508,7 +521,7 @@ struct Parameter {
   /// material
   ColorValue ColorFactor() const {
     return {
-        {// this agregate intialize the std::array object, and uses C++11 RVO.
+        {// this aggregate initialize the std::array object, and uses C++11 RVO.
          number_array[0], number_array[1], number_array[2],
          (number_array.size() > 3 ? number_array[3] : 1.0)}};
   }
@@ -819,7 +832,7 @@ struct BufferView {
   size_t byteStride{0};  // minimum 4, maximum 252 (multiple of 4), default 0 =
                          // understood to be tightly packed
   int target{0};  // ["ARRAY_BUFFER", "ELEMENT_ARRAY_BUFFER"] for vertex indices
-                  // or atttribs. Could be 0 for other data
+                  // or attribs. Could be 0 for other data
   Value extras;
   ExtensionMap extensions;
 
@@ -895,7 +908,7 @@ struct Accessor {
 
       return componentSizeInBytes * numComponents;
     } else {
-      // Check if byteStride is a mulple of the size of the accessor's component
+      // Check if byteStride is a multiple of the size of the accessor's component
       // type.
       int componentSizeInBytes =
           GetComponentSizeInBytes(static_cast<uint32_t>(componentType));
@@ -934,7 +947,7 @@ struct PerspectiveCamera {
   PerspectiveCamera()
       : aspectRatio(0.0),
         yfov(0.0),
-        zfar(0.0)  // 0 = use infinite projecton matrix
+        zfar(0.0)  // 0 = use infinite projection matrix
         ,
         znear(0.0) {}
   DEFAULT_METHODS(PerspectiveCamera)
@@ -995,7 +1008,7 @@ struct Primitive {
   int indices;   // The index of the accessor that contains the indices.
   int mode;      // one of TINYGLTF_MODE_***
   std::vector<std::map<std::string, int> > targets;  // array of morph targets,
-  // where each target is a dict with attribues in ["POSITION, "NORMAL",
+  // where each target is a dict with attributes in ["POSITION, "NORMAL",
   // "TANGENT"] pointing
   // to their corresponding accessors
   ExtensionMap extensions;
@@ -1130,7 +1143,7 @@ struct Light {
   std::vector<double> color;
   double intensity{1.0};
   std::string type;
-  double range{0.0};  // 0.0 = inifinite
+  double range{0.0};  // 0.0 = infinite
   SpotLight spot;
 
   Light() : intensity(1.0), range(0.0) {}
@@ -1204,9 +1217,13 @@ typedef bool (*LoadImageDataFunction)(Image *, const int, std::string *,
 
 ///
 /// WriteImageDataFunction type. Signature for custom image writing callbacks.
+/// The out_uri parameter becomes the URI written to the gltf and may reference
+/// a file or contain a data URI.
 ///
-typedef bool (*WriteImageDataFunction)(const std::string *, const std::string *,
-                                       Image *, bool, void *);
+typedef bool (*WriteImageDataFunction)(const std::string *basepath,
+                                       const std::string *filename,
+                                       const Image *image, bool embedImages,
+                                       std::string *out_uri, void *user_pointer);
 
 #ifndef TINYGLTF_NO_STB_IMAGE
 // Declaration of default image loader callback
@@ -1218,7 +1235,8 @@ bool LoadImageData(Image *image, const int image_idx, std::string *err,
 #ifndef TINYGLTF_NO_STB_IMAGE_WRITE
 // Declaration of default image writer callback
 bool WriteImageData(const std::string *basepath, const std::string *filename,
-                    Image *image, bool embedImages, void *);
+                    const Image *image, bool embedImages, std::string *out_uri,
+                    void *);
 #endif
 
 ///
@@ -1280,7 +1298,7 @@ bool WriteWholeFile(std::string *err, const std::string &filepath,
 #endif
 
 ///
-/// glTF Parser/Serialier context.
+/// glTF Parser/Serializer context.
 ///
 class TinyGLTF {
  public:
@@ -1343,15 +1361,15 @@ class TinyGLTF {
                             unsigned int check_sections = REQUIRE_VERSION);
 
   ///
-  /// Write glTF to stream, buffers and images will be embeded
+  /// Write glTF to stream, buffers and images will be embedded
   ///
-  bool WriteGltfSceneToStream(Model *model, std::ostream &stream,
+  bool WriteGltfSceneToStream(const Model *model, std::ostream &stream,
                               bool prettyPrint, bool writeBinary);
 
   ///
   /// Write glTF to file.
   ///
-  bool WriteGltfSceneToFile(Model *model, const std::string &filename,
+  bool WriteGltfSceneToFile(const Model *model, const std::string &filename,
                             bool embedImages, bool embedBuffers,
                             bool prettyPrint, bool writeBinary);
 
@@ -1378,7 +1396,7 @@ class TinyGLTF {
   ///
   /// Set serializing default values(default = false).
   /// When true, default values are force serialized to .glTF.
-  /// This may be helpfull if you want to serialize a full description of glTF
+  /// This may be helpful if you want to serialize a full description of glTF
   /// data.
   ///
   /// TODO(LTE): Supply parsing option as function arguments to
@@ -1404,8 +1422,8 @@ class TinyGLTF {
   }
 
   ///
-  /// Specify whether preserve image channales when loading images or not.
-  /// (Not effective when the user suppy their own LoadImageData callbacks)
+  /// Specify whether preserve image channels when loading images or not.
+  /// (Not effective when the user supplies their own LoadImageData callbacks)
   ///
   void SetPreserveImageChannels(bool onoff) {
     preserve_image_channels_ = onoff;
@@ -1542,7 +1560,7 @@ class TinyGLTF {
 #endif
 #endif
 
-// Disable GCC warnigs
+// Disable GCC warnings
 #ifdef __GNUC__
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wtype-limits"
@@ -1591,7 +1609,7 @@ class TinyGLTF {
 
 // issue 143.
 // Define NOMINMAX to avoid min/max defines,
-// but undef it after included windows.h
+// but undef it after included Windows.h
 #ifndef NOMINMAX
 #define TINYGLTF_INTERNAL_NOMINMAX
 #define NOMINMAX
@@ -1601,7 +1619,11 @@ class TinyGLTF {
 #define WIN32_LEAN_AND_MEAN
 #define TINYGLTF_INTERNAL_WIN32_LEAN_AND_MEAN
 #endif
-#include <windows.h>  // include API for expanding a file path
+#ifndef __MINGW32__
+#include <Windows.h>  // include API for expanding a file path
+#else
+#include <windows.h>
+#endif
 
 #ifdef TINYGLTF_INTERNAL_WIN32_LEAN_AND_MEAN
 #undef WIN32_LEAN_AND_MEAN
@@ -1732,7 +1754,7 @@ namespace tinygltf {
 struct LoadImageDataOption {
   // true: preserve image channels(e.g. load as RGB image if the image has RGB
   // channels) default `false`(channels are expanded to RGBA for backward
-  // compatiblity).
+  // compatibility).
   bool preserve_channels{false};
 };
 
@@ -2379,7 +2401,7 @@ bool LoadImageData(Image *image, const int image_idx, std::string *err,
 
   // It is possible that the image we want to load is a 16bit per channel image
   // We are going to attempt to load it as 16bit per channel, and if it worked,
-  // set the image data accodingly. We are casting the returned pointer into
+  // set the image data accordingly. We are casting the returned pointer into
   // unsigned char, because we are representing "bytes". But we are updating
   // the Image metadata to signal that this image uses 2 bytes (16bits) per
   // channel:
@@ -2394,7 +2416,7 @@ bool LoadImageData(Image *image, const int image_idx, std::string *err,
 
   // at this point, if data is still NULL, it means that the image wasn't
   // 16bit per channel, we are going to load it as a normal 8bit per channel
-  // mage as we used to do:
+  // image as we used to do:
   // if image cannot be decoded, ignore parsing and keep it by its path
   // don't break in this case
   // FIXME we should only enter this function if the image is embedded. If
@@ -2479,7 +2501,8 @@ static void WriteToMemory_stbi(void *context, void *data, int size) {
 }
 
 bool WriteImageData(const std::string *basepath, const std::string *filename,
-                    Image *image, bool embedImages, void *fsPtr) {
+                    const Image *image, bool embedImages, std::string *out_uri,
+                    void *fsPtr) {
   const std::string ext = GetFilePathExtension(*filename);
 
   // Write image to temporary buffer
@@ -2521,9 +2544,8 @@ bool WriteImageData(const std::string *basepath, const std::string *filename,
   if (embedImages) {
     // Embed base64-encoded image into URI
     if (data.size()) {
-      image->uri =
-          header +
-          base64_encode(&data[0], static_cast<unsigned int>(data.size()));
+      *out_uri = header +
+                base64_encode(&data[0], static_cast<unsigned int>(data.size()));
     } else {
       // Throw error?
     }
@@ -2541,7 +2563,7 @@ bool WriteImageData(const std::string *basepath, const std::string *filename,
     } else {
       // Throw error?
     }
-    image->uri = *filename;
+    *out_uri = *filename;
   }
 
   return true;
@@ -2554,7 +2576,7 @@ void TinyGLTF::SetFsCallbacks(FsCallbacks callbacks) { fs = callbacks; }
 static inline std::wstring UTF8ToWchar(const std::string &str) {
   int wstr_size =
       MultiByteToWideChar(CP_UTF8, 0, str.data(), (int)str.size(), nullptr, 0);
-  std::wstring wstr(wstr_size, 0);
+  std::wstring wstr((size_t)wstr_size, 0);
   MultiByteToWideChar(CP_UTF8, 0, str.data(), (int)str.size(), &wstr[0],
                       (int)wstr.size());
   return wstr;
@@ -2562,10 +2584,10 @@ static inline std::wstring UTF8ToWchar(const std::string &str) {
 
 static inline std::string WcharToUTF8(const std::wstring &wstr) {
   int str_size = WideCharToMultiByte(CP_UTF8, 0, wstr.data(), (int)wstr.size(),
-                                     nullptr, 0, NULL, NULL);
-  std::string str(str_size, 0);
+                                     nullptr, 0, nullptr, nullptr);
+  std::string str((size_t)str_size, 0);
   WideCharToMultiByte(CP_UTF8, 0, wstr.data(), (int)wstr.size(), &str[0],
-                      (int)str.size(), NULL, NULL);
+                      (int)str.size(), nullptr, nullptr);
   return str;
 }
 #endif
@@ -2589,7 +2611,7 @@ bool FileExists(const std::string &abs_filename, void *) {
   }
 #else
 #ifdef _WIN32
-#if defined(_MSC_VER) || defined(__GLIBCXX__)
+#if defined(_MSC_VER) || defined(__GLIBCXX__) || defined(_LIBCPP_VERSION)
   FILE *fp = nullptr;
   errno_t err = _wfopen_s(&fp, UTF8ToWchar(abs_filename).c_str(), L"rb");
   if (err != 0) {
@@ -2812,13 +2834,13 @@ static std::string MimeToExt(const std::string &mimeType) {
   return "";
 }
 
-static void UpdateImageObject(Image &image, std::string &baseDir, int index,
-                              bool embedImages,
-                              WriteImageDataFunction *WriteImageData = nullptr,
-                              void *user_data = nullptr) {
+static void UpdateImageObject(const Image &image, std::string &baseDir,
+                              int index, bool embedImages,
+                              WriteImageDataFunction *WriteImageData,
+                              std::string *out_uri, void *user_data) {
   std::string filename;
   std::string ext;
-  // If image has uri, use it it as a filename
+  // If image has uri, use it as a filename
   if (image.uri.size()) {
     filename = GetBaseFilename(image.uri);
     ext = GetFilePathExtension(filename);
@@ -2836,9 +2858,15 @@ static void UpdateImageObject(Image &image, std::string &baseDir, int index,
   }
 
   // If callback is set, modify image data object
+  bool imageWritten = false;
   if (*WriteImageData != nullptr && !filename.empty()) {
-    std::string uri;
-    (*WriteImageData)(&baseDir, &filename, &image, embedImages, user_data);
+    imageWritten = (*WriteImageData)(&baseDir, &filename, &image, embedImages,
+                                     out_uri, user_data);
+  }
+
+  // Use the original uri if the image was not written.
+  if (!imageWritten) {
+    *out_uri = image.uri;
   }
 }
 
@@ -3229,9 +3257,11 @@ static bool ParseJsonAsValue(Value *ret, const json &o) {
       break;
   }
 #endif
+  const bool isNotNull = val.Type() != NULL_TYPE;
+
   if (ret) *ret = std::move(val);
 
-  return val.Type() != NULL_TYPE;
+  return isNotNull;
 }
 
 static bool ParseExtrasProperty(Value *ret, const json &o) {
@@ -3671,7 +3701,8 @@ static bool ParseParameterProperty(Parameter *param, std::string *err,
     // Found a number array.
     return true;
   } else if (ParseNumberProperty(&param->number_value, err, o, prop, false)) {
-    return param->has_number_value = true;
+    param->has_number_value = true;
+    return true;
   } else if (ParseJSONProperty(&param->json_double_value, err, o, prop,
                                false)) {
     return true;
@@ -3864,7 +3895,7 @@ static bool ParseImage(Image *image, const int image_idx, std::string *err,
     image->uri = uri;
 #ifdef TINYGLTF_NO_EXTERNAL_IMAGE
     return true;
-#endif
+#else
     std::string decoded_uri = dlib::urldecode(uri);
     if (!LoadExternalFile(&img, err, warn, decoded_uri, basedir,
                           /* required */ false, /* required bytes */ 0,
@@ -3886,6 +3917,7 @@ static bool ParseImage(Image *image, const int image_idx, std::string *err,
       }
       return false;
     }
+#endif
   }
 
   if (*LoadImageData == nullptr) {
@@ -4102,7 +4134,7 @@ static bool ParseBuffer(Buffer *buffer, std::string *err, const json &o,
 
       if ((bin_size == 0) || (bin_data == nullptr)) {
         if (err) {
-          (*err) += "Invalid binary data in `Buffer'.\n";
+          (*err) += "Invalid binary data in `Buffer', or GLB with empty BIN chunk.\n";
         }
         return false;
       }
@@ -4260,7 +4292,7 @@ static bool ParseSparseAccessor(Accessor *accessor, std::string *err,
   }
 
   if (!FindMember(o, "values", values_iterator)) {
-    (*err) = "the sparse object ob ths accessor doesn't have values";
+    (*err) = "the sparse object of this accessor doesn't have values";
     return false;
   }
 
@@ -4606,7 +4638,7 @@ static bool ParsePrimitive(Primitive *primitive, Model *model, std::string *err,
 
   int mode = TINYGLTF_MODE_TRIANGLES;
   ParseIntegerProperty(&mode, err, o, "mode", false);
-  primitive->mode = mode;  // Why only triangled were supported ?
+  primitive->mode = mode;  // Why only triangles were supported ?
 
   int indices = -1;
   ParseIntegerProperty(&indices, err, o, "indices", false);
@@ -4889,7 +4921,7 @@ static bool ParseMaterial(Material *material, std::string *err, const json &o,
 
   // Old code path. For backward compatibility, we still store material values
   // as Parameter. This will create duplicated information for
-  // example(pbrMetallicRoughness), but should be neglible in terms of memory
+  // example(pbrMetallicRoughness), but should be negligible in terms of memory
   // consumption.
   // TODO(syoyo): Remove in the next major release.
   material->values.clear();
@@ -4922,7 +4954,7 @@ static bool ParseMaterial(Material *material, std::string *err, const json &o,
       Parameter param;
       if (ParseParameterProperty(&param, err, o, key, false)) {
         // names of materials have already been parsed. Putting it in this map
-        // doesn't correctly reflext the glTF specification
+        // doesn't correctly reflect the glTF specification
         if (key != "name")
           material->additionalValues.emplace(std::move(key), std::move(param));
       }
@@ -5128,7 +5160,7 @@ static bool ParseSampler(Sampler *sampler, std::string *err, const json &o,
   // ParseIntegerProperty(&wrapR, err, o, "wrapR", false);  // tinygltf
   // extension
 
-  // TODO(syoyo): Check the value is alloed one.
+  // TODO(syoyo): Check the value is allowed one.
   // (e.g. we allow 9728(NEAREST), but don't allow 9727)
 
   sampler->minFilter = minFilter;
@@ -5337,7 +5369,7 @@ static bool ParseCamera(Camera *camera, std::string *err, const json &o,
     if (!FindMember(o, "orthographic", orthoIt)) {
       if (err) {
         std::stringstream ss;
-        ss << "Orhographic camera description not found." << std::endl;
+        ss << "Orthographic camera description not found." << std::endl;
         (*err) += ss.str();
       }
       return false;
@@ -5789,25 +5821,32 @@ bool TinyGLTF::LoadFromString(Model *model, std::string *err, std::string *warn,
 
         model->bufferViews[size_t(bufferView)].target =
             TINYGLTF_TARGET_ELEMENT_ARRAY_BUFFER;
-        // we could optionally check if acessors' bufferView type is Scalar, as
+        // we could optionally check if accessors' bufferView type is Scalar, as
         // it should be
       }
 
       for (auto &attribute : primitive.attributes) {
-        model
-            ->bufferViews[size_t(
-                model->accessors[size_t(attribute.second)].bufferView)]
-            .target = TINYGLTF_TARGET_ARRAY_BUFFER;
+        const auto accessorsIndex = size_t(attribute.second);
+        if (accessorsIndex < model->accessors.size()) {
+          const auto bufferView = model->accessors[accessorsIndex].bufferView;
+          // bufferView could be null(-1) for sparse morph target
+          if (bufferView >= 0 && bufferView < (int)model->bufferViews.size()) {
+            model->bufferViews[size_t(bufferView)].target =
+                TINYGLTF_TARGET_ARRAY_BUFFER;
+          }
+        }
       }
 
       for (auto &target : primitive.targets) {
         for (auto &attribute : target) {
-          auto bufferView =
-              model->accessors[size_t(attribute.second)].bufferView;
-          // bufferView could be null(-1) for sparse morph target
-          if (bufferView >= 0) {
-            model->bufferViews[size_t(bufferView)].target =
-                TINYGLTF_TARGET_ARRAY_BUFFER;
+          const auto accessorsIndex = size_t(attribute.second);
+          if (accessorsIndex < model->accessors.size()) {
+            const auto bufferView = model->accessors[accessorsIndex].bufferView;
+            // bufferView could be null(-1) for sparse morph target
+            if (bufferView >= 0 && bufferView < (int)model->bufferViews.size()) {
+              model->bufferViews[size_t(bufferView)].target =
+                  TINYGLTF_TARGET_ARRAY_BUFFER;
+            }
           }
         }
       }
@@ -6268,15 +6307,15 @@ bool TinyGLTF::LoadBinaryFromMemory(Model *model, std::string *err,
   //
   // https://github.com/syoyo/tinygltf/issues/372
   // Use 64bit uint to avoid integer overflow.
-  uint64_t json_size = 20ull + uint64_t(chunk0_length);
+  uint64_t header_and_json_size = 20ull + uint64_t(chunk0_length);
 
-  if (json_size > std::numeric_limits<uint32_t>::max()) {
+  if (header_and_json_size > std::numeric_limits<uint32_t>::max()) {
     // Do not allow 4GB or more GLB data.
    (*err) = "Invalid glTF binary. GLB data exceeds 4GB.";
   }
 
-  if ((json_size > uint64_t(size)) || (chunk0_length < 1) || (length > size) ||
-      (json_size > uint64_t(length)) ||
+  if ((header_and_json_size > uint64_t(size)) || (chunk0_length < 1) || (length > size) ||
+      (header_and_json_size > uint64_t(length)) ||
       (chunk0_format != 0x4E4F534A)) {  // 0x4E4F534A = JSON format.
     if (err) {
       (*err) = "Invalid glTF binary.";
@@ -6287,61 +6326,77 @@ bool TinyGLTF::LoadBinaryFromMemory(Model *model, std::string *err,
   // Padding check
   // The start and the end of each chunk must be aligned to a 4-byte boundary.
   // No padding check for chunk0 start since its 4byte-boundary is ensured.
-  if ((json_size % 4) != 0) {
+  if ((header_and_json_size % 4) != 0) {
     if (err) {
       (*err) = "JSON Chunk end does not aligned to a 4-byte boundary.";
     }
   }
 
-  // Read Chunk1 info(BIN data)
-  if ((json_size + 8ull) > uint64_t(length)) {
-    if (err) {
-      (*err) = "Insufficient storage space for Chunk1(BIN data).";
+  //std::cout << "header_and_json_size = " << header_and_json_size << "\n";
+  //std::cout << "length = " << length << "\n";
+
+  // Chunk1(BIN) data
+  // The spec says: When the binary buffer is empty or when it is stored by other means, this chunk SHOULD be omitted.
+  // So when header + JSON data == binary size, Chunk1 is omitted.
+  if (header_and_json_size == uint64_t(length)) {
+
+    bin_data_ = nullptr;
+    bin_size_ = 0;
+  } else {
+    // Read Chunk1 info(BIN data)
+    // At least Chunk1 should have 12 bytes(8 bytes(header) + 4 bytes(bin payload could be 1~3 bytes, but need to be aligned to 4 bytes)
+    if ((header_and_json_size + 12ull) > uint64_t(length)) {
+      if (err) {
+        (*err) = "Insufficient storage space for Chunk1(BIN data). At least Chunk1 Must have 4 bytes or more bytes, but got " + std::to_string((header_and_json_size + 12ull) - uint64_t(length)) + ".\n";
+      }
+      return false;
     }
-    return false;
-  }
 
-  unsigned int chunk1_length;  // 4 bytes
-  unsigned int chunk1_format;  // 4 bytes;
-  memcpy(&chunk1_length, bytes + json_size, 4); // JSON data length
-  swap4(&chunk1_length);
-  memcpy(&chunk1_format, bytes + json_size + 4, 4);
-  swap4(&chunk1_format);
+    unsigned int chunk1_length;  // 4 bytes
+    unsigned int chunk1_format;  // 4 bytes;
+    memcpy(&chunk1_length, bytes + header_and_json_size, 4); // JSON data length
+    swap4(&chunk1_length);
+    memcpy(&chunk1_format, bytes + header_and_json_size + 4, 4);
+    swap4(&chunk1_format);
 
-  if (chunk1_length < 4) {
-    // TODO: Do we allow 0byte BIN data?
-    if (err) {
-      (*err) = "Insufficient Chunk1(BIN) data size.";
+    //std::cout << "chunk1_length = " << chunk1_length << "\n";
+
+    if (chunk1_length < 4) {
+      if (err) {
+        (*err) = "Insufficient Chunk1(BIN) data size.";
+      }
+      return false;
     }
-    return false;
-  }
 
-  if ((chunk1_length % 4) != 0) {
-    if (err) {
-      (*err) = "BIN Chunk end does not aligned to a 4-byte boundary.";
+    if ((chunk1_length % 4) != 0) {
+      if (err) {
+        (*err) = "BIN Chunk end does not aligned to a 4-byte boundary.";
+      }
+      return false;
     }
-    return false;
-  }
 
-  if (uint64_t(chunk1_length) + json_size > uint64_t(length)) {
-    if (err) {
-      (*err) = "BIN Chunk data length exceeds the GLB size.";
+    if (uint64_t(chunk1_length) + header_and_json_size > uint64_t(length)) {
+      if (err) {
+        (*err) = "BIN Chunk data length exceeds the GLB size.";
+      }
+      return false;
     }
-    return false;
-  }
 
-  if (chunk1_format != 0x004e4942) {
-    if (err) {
-      (*err) = "Invlid type for chunk1 data.";
+    if (chunk1_format != 0x004e4942) {
+      if (err) {
+        (*err) = "Invalid type for chunk1 data.";
+      }
+      return false;
     }
-    return false;
+
+    //std::cout << "chunk1_length = " << chunk1_length << "\n";
+
+    bin_data_ = bytes + header_and_json_size +
+                8;  // 4 bytes (bin_buffer_length) + 4 bytes(bin_buffer_format)
+
+    bin_size_ = size_t(chunk1_length);
   }
 
-  bin_data_ = bytes + json_size +
-              8;  // 4 bytes (bin_buffer_length) + 4 bytes(bin_buffer_format)
-
-  bin_size_ = size_t(chunk1_length);
-
   // Extract JSON string.
   std::string jsonString(reinterpret_cast<const char *>(&bytes[20]),
                          chunk0_length);
@@ -6618,7 +6673,7 @@ static void SerializeGltfBufferData(const std::vector<unsigned char> &data,
     SerializeStringProperty("uri", header + encodedData, o);
   } else {
     // Issue #229
-    // size 0 is allowd. Just emit mime header.
+    // size 0 is allowed. Just emit mime header.
     SerializeStringProperty("uri", header, o);
   }
 }
@@ -6712,7 +6767,7 @@ static void SerializeExtensionMap(const ExtensionMap &extensions, json &o) {
   JsonAddMember(o, "extensions", std::move(extMap));
 }
 
-static void SerializeGltfAccessor(Accessor &accessor, json &o) {
+static void SerializeGltfAccessor(const Accessor &accessor, json &o) {
   if (accessor.bufferView >= 0)
     SerializeNumberProperty<int>("bufferView", accessor.bufferView, o);
 
@@ -6804,7 +6859,8 @@ static void SerializeGltfAccessor(Accessor &accessor, json &o) {
   }
 }
 
-static void SerializeGltfAnimationChannel(AnimationChannel &channel, json &o) {
+static void SerializeGltfAnimationChannel(const AnimationChannel &channel,
+                                          json &o) {
   SerializeNumberProperty("sampler", channel.sampler, o);
   {
     json target;
@@ -6823,7 +6879,8 @@ static void SerializeGltfAnimationChannel(AnimationChannel &channel, json &o) {
   SerializeExtensionMap(channel.extensions, o);
 }
 
-static void SerializeGltfAnimationSampler(AnimationSampler &sampler, json &o) {
+static void SerializeGltfAnimationSampler(const AnimationSampler &sampler,
+                                          json &o) {
   SerializeNumberProperty("input", sampler.input, o);
   SerializeNumberProperty("output", sampler.output, o);
   SerializeStringProperty("interpolation", sampler.interpolation, o);
@@ -6833,7 +6890,7 @@ static void SerializeGltfAnimationSampler(AnimationSampler &sampler, json &o) {
   }
 }
 
-static void SerializeGltfAnimation(Animation &animation, json &o) {
+static void SerializeGltfAnimation(const Animation &animation, json &o) {
   if (!animation.name.empty())
     SerializeStringProperty("name", animation.name, o);
 
@@ -6869,7 +6926,7 @@ static void SerializeGltfAnimation(Animation &animation, json &o) {
   SerializeExtensionMap(animation.extensions, o);
 }
 
-static void SerializeGltfAsset(Asset &asset, json &o) {
+static void SerializeGltfAsset(const Asset &asset, json &o) {
   if (!asset.generator.empty()) {
     SerializeStringProperty("generator", asset.generator, o);
   }
@@ -6878,14 +6935,15 @@ static void SerializeGltfAsset(Asset &asset, json &o) {
     SerializeStringProperty("copyright", asset.copyright, o);
   }
 
-  if (asset.version.empty()) {
+  auto version = asset.version;
+  if (version.empty()) {
     // Just in case
     // `version` must be defined
-    asset.version = "2.0";
+    version = "2.0";
   }
 
   // TODO(syoyo): Do we need to check if `version` is greater or equal to 2.0?
-  SerializeStringProperty("version", asset.version, o);
+  SerializeStringProperty("version", version, o);
 
   if (asset.extras.Keys().size()) {
     SerializeValue("extras", asset.extras, o);
@@ -6894,7 +6952,7 @@ static void SerializeGltfAsset(Asset &asset, json &o) {
   SerializeExtensionMap(asset.extensions, o);
 }
 
-static void SerializeGltfBufferBin(Buffer &buffer, json &o,
+static void SerializeGltfBufferBin(const Buffer &buffer, json &o,
                                    std::vector<unsigned char> &binBuffer) {
   SerializeNumberProperty("byteLength", buffer.data.size(), o);
   binBuffer = buffer.data;
@@ -6906,7 +6964,7 @@ static void SerializeGltfBufferBin(Buffer &buffer, json &o,
   }
 }
 
-static void SerializeGltfBuffer(Buffer &buffer, json &o) {
+static void SerializeGltfBuffer(const Buffer &buffer, json &o) {
   SerializeNumberProperty("byteLength", buffer.data.size(), o);
   SerializeGltfBufferData(buffer.data, o);
 
@@ -6917,7 +6975,7 @@ static void SerializeGltfBuffer(Buffer &buffer, json &o) {
   }
 }
 
-static bool SerializeGltfBuffer(Buffer &buffer, json &o,
+static bool SerializeGltfBuffer(const Buffer &buffer, json &o,
                                 const std::string &binFilename,
                                 const std::string &binBaseFilename) {
   if (!SerializeGltfBufferData(buffer.data, binFilename)) return false;
@@ -6932,7 +6990,7 @@ static bool SerializeGltfBuffer(Buffer &buffer, json &o,
   return true;
 }
 
-static void SerializeGltfBufferView(BufferView &bufferView, json &o) {
+static void SerializeGltfBufferView(const BufferView &bufferView, json &o) {
   SerializeNumberProperty("buffer", bufferView.buffer, o);
   SerializeNumberProperty<size_t>("byteLength", bufferView.byteLength, o);
 
@@ -6958,14 +7016,16 @@ static void SerializeGltfBufferView(BufferView &bufferView, json &o) {
   }
 }
 
-static void SerializeGltfImage(Image &image, json &o) {
-  // if uri empty, the mimeType and bufferview should be set
-  if (image.uri.empty()) {
+static void SerializeGltfImage(const Image &image, const std::string uri,
+                               json &o) {
+  // From 2.7.0, we look for `uri` parameter, not `Image.uri`
+  // if uri is empty, the mimeType and bufferview should be set
+  if (uri.empty()) {
     SerializeStringProperty("mimeType", image.mimeType, o);
     SerializeNumberProperty<int>("bufferView", image.bufferView, o);
   } else {
     // TODO(syoyo): dlib::urilencode?
-    SerializeStringProperty("uri", image.uri, o);
+    SerializeStringProperty("uri", uri, o);
   }
 
   if (image.name.size()) {
@@ -6979,7 +7039,7 @@ static void SerializeGltfImage(Image &image, json &o) {
   SerializeExtensionMap(image.extensions, o);
 }
 
-static void SerializeGltfTextureInfo(TextureInfo &texinfo, json &o) {
+static void SerializeGltfTextureInfo(const TextureInfo &texinfo, json &o) {
   SerializeNumberProperty("index", texinfo.index, o);
 
   if (texinfo.texCoord != 0) {
@@ -6993,7 +7053,7 @@ static void SerializeGltfTextureInfo(TextureInfo &texinfo, json &o) {
   SerializeExtensionMap(texinfo.extensions, o);
 }
 
-static void SerializeGltfNormalTextureInfo(NormalTextureInfo &texinfo,
+static void SerializeGltfNormalTextureInfo(const NormalTextureInfo &texinfo,
                                            json &o) {
   SerializeNumberProperty("index", texinfo.index, o);
 
@@ -7012,8 +7072,8 @@ static void SerializeGltfNormalTextureInfo(NormalTextureInfo &texinfo,
   SerializeExtensionMap(texinfo.extensions, o);
 }
 
-static void SerializeGltfOcclusionTextureInfo(OcclusionTextureInfo &texinfo,
-                                              json &o) {
+static void SerializeGltfOcclusionTextureInfo(
+    const OcclusionTextureInfo &texinfo, json &o) {
   SerializeNumberProperty("index", texinfo.index, o);
 
   if (texinfo.texCoord != 0) {
@@ -7031,7 +7091,7 @@ static void SerializeGltfOcclusionTextureInfo(OcclusionTextureInfo &texinfo,
   SerializeExtensionMap(texinfo.extensions, o);
 }
 
-static void SerializeGltfPbrMetallicRoughness(PbrMetallicRoughness &pbr,
+static void SerializeGltfPbrMetallicRoughness(const PbrMetallicRoughness &pbr,
                                               json &o) {
   std::vector<double> default_baseColorFactor = {1.0, 1.0, 1.0, 1.0};
   if (!Equals(pbr.baseColorFactor, default_baseColorFactor)) {
@@ -7066,7 +7126,7 @@ static void SerializeGltfPbrMetallicRoughness(PbrMetallicRoughness &pbr,
   }
 }
 
-static void SerializeGltfMaterial(Material &material, json &o) {
+static void SerializeGltfMaterial(const Material &material, json &o) {
   if (material.name.size()) {
     SerializeStringProperty("name", material.name, o);
   }
@@ -7116,7 +7176,7 @@ static void SerializeGltfMaterial(Material &material, json &o) {
     // Do not serialize `pbrMetallicRoughness` if pbrMetallicRoughness has all
     // default values(json is null). Otherwise it will serialize to
     // `pbrMetallicRoughness : null`, which cannot be read by other glTF
-    // importers(and validators).
+    // importers (and validators).
     //
     if (!JsonIsNull(pbrMetallicRoughness)) {
       JsonAddMember(o, "pbrMetallicRoughness", std::move(pbrMetallicRoughness));
@@ -7142,7 +7202,7 @@ static void SerializeGltfMaterial(Material &material, json &o) {
   }
 }
 
-static void SerializeGltfMesh(Mesh &mesh, json &o) {
+static void SerializeGltfMesh(const Mesh &mesh, json &o) {
   json primitives;
   JsonReserveArray(primitives, mesh.primitives.size());
   for (unsigned int i = 0; i < mesh.primitives.size(); ++i) {
@@ -7158,7 +7218,7 @@ static void SerializeGltfMesh(Mesh &mesh, json &o) {
       JsonAddMember(primitive, "attributes", std::move(attributes));
     }
 
-    // Indicies is optional
+    // Indices is optional
     if (gltfPrimitive.indices > -1) {
       SerializeNumberProperty<int>("indices", gltfPrimitive.indices, primitive);
     }
@@ -7211,7 +7271,7 @@ static void SerializeGltfMesh(Mesh &mesh, json &o) {
   }
 }
 
-static void SerializeSpotLight(SpotLight &spot, json &o) {
+static void SerializeSpotLight(const SpotLight &spot, json &o) {
   SerializeNumberProperty("innerConeAngle", spot.innerConeAngle, o);
   SerializeNumberProperty("outerConeAngle", spot.outerConeAngle, o);
   SerializeExtensionMap(spot.extensions, o);
@@ -7220,7 +7280,7 @@ static void SerializeSpotLight(SpotLight &spot, json &o) {
   }
 }
 
-static void SerializeGltfLight(Light &light, json &o) {
+static void SerializeGltfLight(const Light &light, json &o) {
   if (!light.name.empty()) SerializeStringProperty("name", light.name, o);
   SerializeNumberProperty("intensity", light.intensity, o);
   if (light.range > 0.0) {
@@ -7239,7 +7299,7 @@ static void SerializeGltfLight(Light &light, json &o) {
   }
 }
 
-static void SerializeGltfNode(Node &node, json &o) {
+static void SerializeGltfNode(const Node &node, json &o) {
   if (node.translation.size() > 0) {
     SerializeNumberArrayProperty<double>("translation", node.translation, o);
   }
@@ -7277,7 +7337,7 @@ static void SerializeGltfNode(Node &node, json &o) {
   SerializeNumberArrayProperty<int>("children", node.children, o);
 }
 
-static void SerializeGltfSampler(Sampler &sampler, json &o) {
+static void SerializeGltfSampler(const Sampler &sampler, json &o) {
   if (sampler.magFilter != -1) {
     SerializeNumberProperty("magFilter", sampler.magFilter, o);
   }
@@ -7346,7 +7406,7 @@ static void SerializeGltfCamera(const Camera &camera, json &o) {
   SerializeExtensionMap(camera.extensions, o);
 }
 
-static void SerializeGltfScene(Scene &scene, json &o) {
+static void SerializeGltfScene(const Scene &scene, json &o) {
   SerializeNumberArrayProperty<int>("nodes", scene.nodes, o);
 
   if (scene.name.size()) {
@@ -7358,7 +7418,7 @@ static void SerializeGltfScene(Scene &scene, json &o) {
   SerializeExtensionMap(scene.extensions, o);
 }
 
-static void SerializeGltfSkin(Skin &skin, json &o) {
+static void SerializeGltfSkin(const Skin &skin, json &o) {
   // required
   SerializeNumberArrayProperty<int>("joints", skin.joints, o);
 
@@ -7375,7 +7435,7 @@ static void SerializeGltfSkin(Skin &skin, json &o) {
   }
 }
 
-static void SerializeGltfTexture(Texture &texture, json &o) {
+static void SerializeGltfTexture(const Texture &texture, json &o) {
   if (texture.sampler > -1) {
     SerializeNumberProperty("sampler", texture.sampler, o);
   }
@@ -7394,7 +7454,7 @@ static void SerializeGltfTexture(Texture &texture, json &o) {
 ///
 /// Serialize all properties except buffers and images.
 ///
-static void SerializeGltfModel(Model *model, json &o) {
+static void SerializeGltfModel(const Model *model, json &o) {
   // ACCESSORS
   if (model->accessors.size()) {
     json accessors;
@@ -7720,7 +7780,7 @@ static bool WriteBinaryGltfFile(const std::string &output,
   return WriteBinaryGltfStream(gltfFile, content, binBuffer);
 }
 
-bool TinyGLTF::WriteGltfSceneToStream(Model *model, std::ostream &stream,
+bool TinyGLTF::WriteGltfSceneToStream(const Model *model, std::ostream &stream,
                                       bool prettyPrint = true,
                                       bool writeBinary = false) {
   JsonDocument output;
@@ -7756,9 +7816,11 @@ bool TinyGLTF::WriteGltfSceneToStream(Model *model, std::ostream &stream,
       // UpdateImageObject need baseDir but only uses it if embeddedImages is
       // enabled, since we won't write separate images when writing to a stream
       // we
+      std::string uri;
       UpdateImageObject(model->images[i], dummystring, int(i), true,
-                        &this->WriteImageData, this->write_image_user_data_);
-      SerializeGltfImage(model->images[i], image);
+                        &this->WriteImageData, &uri,
+                        this->write_image_user_data_);
+      SerializeGltfImage(model->images[i], uri, image);
       JsonPushBack(images, std::move(image));
     }
     JsonAddMember(output, "images", std::move(images));
@@ -7769,10 +7831,10 @@ bool TinyGLTF::WriteGltfSceneToStream(Model *model, std::ostream &stream,
   } else {
     return WriteGltfStream(stream, JsonToString(output, prettyPrint ? 2 : -1));
   }
-
 }
 
-bool TinyGLTF::WriteGltfSceneToFile(Model *model, const std::string &filename,
+bool TinyGLTF::WriteGltfSceneToFile(const Model *model,
+                                    const std::string &filename,
                                     bool embedImages = false,
                                     bool embedBuffers = false,
                                     bool prettyPrint = true,
@@ -7845,9 +7907,11 @@ bool TinyGLTF::WriteGltfSceneToFile(Model *model, const std::string &filename,
     for (unsigned int i = 0; i < model->images.size(); ++i) {
       json image;
 
+      std::string uri;
       UpdateImageObject(model->images[i], baseDir, int(i), embedImages,
-                        &this->WriteImageData, this->write_image_user_data_);
-      SerializeGltfImage(model->images[i], image);
+                        &this->WriteImageData, &uri,
+                        this->write_image_user_data_);
+      SerializeGltfImage(model->images[i], uri, image);
       JsonPushBack(images, std::move(image));
     }
     JsonAddMember(output, "images", std::move(images));
@@ -7858,7 +7922,6 @@ bool TinyGLTF::WriteGltfSceneToFile(Model *model, const std::string &filename,
   } else {
     return WriteGltfFile(filename, JsonToString(output, (prettyPrint ? 2 : -1)));
   }
-
 }
 
 }  // namespace tinygltf

wasm/Makefile

@@ -0,0 +1,11 @@
+WASI_VERSION=16
+WASI_VERSION_FULL=${WASI_VERSION}.0
+
+WASI_SDK_PATH=$(HOME)/local/wasi-sdk-${WASI_VERSION_FULL}
+
+CC=${WASI_SDK_PATH}/bin/clang
+CXX=${WASI_SDK_PATH}/bin/clang++
+CXXFLAGS=-fno-rtti -fno-exceptions -g -Os
+
+all:
+	$(CXX) ../loader_example.cc $(CXXFLAGS) -I../

wasm/README.md

@@ -0,0 +1,31 @@
+Experimental WASI/WASM build
+
+## Build
+
+Download wasi-sdk https://github.com/WebAssembly/wasi-sdk
+
+Compile tinygltf with C++ exceptions and threads off. See `Makefile` for details
+(NOTE: TinyGLTF itself does not use RTTI and threading feature(C++ threads, posix, win32 thread))
+
+## Build examples and Run
+
+Build `loader_example.cc`
+
+```
+$ /path/to/wasi-sdk-16.0/bin/clang++ ../loader_example.cc -fno-rtti -fno-exceptions -g -Os -I../ -o loader_example.wasi
+```
+
+Tested with wasmtime.  https://github.com/bytecodealliance/wasmtime
+
+
+Set a folder containing .gltf file to `--dir`
+
+```
+$ wasmtime --dir=../models loader_example.wasi ../models/Cube/Cube.gltf
+```
+
+## Emscripen
+
+T.B.W. ...
+
+EoL.