text: #include "data/modelData.h"
  #include "data/blob.h"
  #include "data/image.h"
  #include "core/maf.h"
  #include "lib/jsmn/jsmn.h"
  #include <stdbool.h>
  #include <stdlib.h>
  #include <string.h>
  #include <ctype.h>
  
  #define MAX_STACK_TOKENS 1024
  
  #define MAGIC_glTF 0x46546c67
  #define MAGIC_JSON 0x4e4f534a
  #define MAGIC_BIN 0x004e4942
  
  #define STR_EQ(k, s) !strncmp(k.data, s, k.length)
  #define NOM_VALUE(j, t) nomValue(j, t, 1, 0)
  #define NOM_INT(j, t) nomInt(j + (t++)->start)
  #define NOM_STR(j, t) (gltfString) { (char* )j + t->start, t->end - t->start }; t++
  #define NOM_BOOL(j, t) (*(j + (t++)->start) == 't')
  #define NOM_FLOAT(j, t) atof(j + (t++)->start)
  
  typedef struct {
    char* data;
    size_t length;
  } gltfString;
  
  typedef struct {
    uint32_t magic;
    uint32_t version;
    uint32_t length;
  } gltfHeader;
  
  typedef struct {
    uint32_t length;
    uint32_t type;
  } gltfChunkHeader;
  
  typedef struct {
    uint32_t input;
    uint32_t output;
    SmoothMode smoothing;
  } gltfAnimationSampler;
  
  typedef struct {
    uint32_t primitiveIndex;
    uint32_t primitiveCount;
  } gltfMesh;
  
  typedef struct {
    TextureFilter filter;
    TextureWrap wrap;
  } gltfSampler;
  
  typedef struct {
    uint32_t image;
    uint32_t sampler;
  } gltfTexture;
  
  typedef struct {
    uint32_t node;
    uint32_t nodeCount;
  } gltfScene;
  
  static uint32_t nomInt(const char* s) {
    uint32_t n = 0;
    lovrAssert(*s != '-', "Expected a positive number");
    while (isdigit(*s)) { n = 10 * n + (*s++ - '0'); }
    return n;
  }
  
  static int nomValue(const char* data, jsmntok_t* token, int count, int sum) {
    if (count == 0) { return sum; }
    switch (token->type) {
      case JSMN_OBJECT: return nomValue(data, token + 1, count - 1 + 2 * token->size, sum + 1);
      case JSMN_ARRAY: return nomValue(data, token + 1, count - 1 + token->size, sum + 1);
      default: return nomValue(data, token + 1, count - 1, sum + 1);
    }
  }
  
  static void* decodeBase64(char* str, size_t length, size_t decodedSize) {
    str = memchr(str, ',', length);
    if (!str) {
      return NULL;
    } else {
      str++;
    }
  
    uint8_t* data = malloc(decodedSize);
    if (!data) {
      return NULL;
    }
  
    uint32_t num = 0;
    uint32_t bits = 0;
    for (size_t i = 0; i < decodedSize; i++) {
      while (bits < 8) {
        char c = *str++;
  
        uint32_t n;
        if (c >= 'A' && c <= 'Z') {
          n = c - 'A';
        } else if (c >= 'a' && c <= 'z') {
          n = c - 'a' + 26;
        } else if (c >= '0' && c <= '9') {
          n = c - '0' + 52;
        } else if (c == '+') {
          n = 62;
        } else if (c == '/') {
          n = 63;
        } else {
          free(data);
          return NULL;
        }
  
        num <<= 6;
        num |= n;
        bits += 6;
      }
  
      data[i] = num >> (bits - 8);
      bits -= 8;
    }
  
    return data;
  }
  
  static jsmntok_t* resolveTexture(const char* json, jsmntok_t* token, ModelMaterial* material, MaterialTexture textureType, gltfTexture* textures, gltfSampler* samplers) {
    for (int k = (token++)->size; k > 0; k--) {
      gltfString key = NOM_STR(json, token);
      if (STR_EQ(key, "index")) {
        uint32_t index = NOM_INT(json, token);
        gltfTexture* texture = &textures[index];
        gltfSampler* sampler = texture->sampler == ~0u ? NULL : &samplers[texture->sampler];
        material->images[textureType] = texture->image;
        material->filters[textureType] = sampler ? sampler->filter : (TextureFilter) { .mode = FILTER_BILINEAR };
        material->wraps[textureType] = sampler ? sampler->wrap : (TextureWrap) { .s = WRAP_REPEAT, .t = WRAP_REPEAT, .r = WRAP_REPEAT };
      } else if (STR_EQ(key, "texCoord")) {
        lovrAssert(NOM_INT(json, token) == 0, "Only one set of texture coordinates is supported");
      } else {
        token += NOM_VALUE(json, token);
      }
    }
    return token;
  }
  
  ModelData* lovrModelDataInitGltf(ModelData* model, Blob* source, ModelDataIO* io) {
    uint8_t* data = source->data;
    gltfHeader* header = (gltfHeader*) data;
    bool glb = source->size >= sizeof(gltfHeader) && header->magic == MAGIC_glTF;
    const char *json, *binData;
    size_t jsonLength;
    ptrdiff_t binOffset;
  
    char filename[1024];
    lovrAssert(strlen(source->name) < sizeof(filename), "glTF filename is too long");
    strcpy(filename, source->name);
    char* slash = strrchr(filename, '/');
    char* root = slash ? (slash + 1) : filename;
    size_t maxPathLength = sizeof(filename) - (root - filename);
    *root = '\0';
  
    if (glb) {
      gltfChunkHeader* jsonHeader = (gltfChunkHeader*) &header[1];
      lovrAssert(jsonHeader->type == MAGIC_JSON, "Invalid JSON header");
  
      json = (char*) &jsonHeader[1];
      jsonLength = jsonHeader->length;
  
      gltfChunkHeader* binHeader = (gltfChunkHeader*) &json[jsonLength];
      lovrAssert(binHeader->type == MAGIC_BIN, "Invalid BIN header");
  
      binData = (char*) &binHeader[1];
      binOffset = (char*) binData - (char*) source->data;
    } else {
      json = (char*) data;
      jsonLength = source->size;
      binData = NULL;
      binOffset = 0;
    }
  
    // Parse JSON
    jsmn_parser parser;
    jsmn_init(&parser);
  
    jsmntok_t stackTokens[MAX_STACK_TOKENS];
    jsmntok_t* heapTokens = NULL;
    jsmntok_t* tokens = &stackTokens[0];
    int tokenCount = 0;
  
    if ((tokenCount = jsmn_parse(&parser, json, jsonLength, stackTokens, MAX_STACK_TOKENS)) == JSMN_ERROR_NOMEM) {
      int capacity = MAX_STACK_TOKENS;
      jsmn_init(&parser); // This shouldn't be necessary but not doing it caused an infinite loop?
  
      do {
        capacity *= 2;
        heapTokens = realloc(heapTokens, capacity * sizeof(jsmntok_t));
        lovrAssert(heapTokens, "Out of memory");
        tokenCount = jsmn_parse(&parser, json, jsonLength, heapTokens, capacity);
      } while (tokenCount == JSMN_ERROR_NOMEM);
  
      tokens = heapTokens;
    }
  
    if (tokenCount <= 0 || tokens[0].type != JSMN_OBJECT) {
      free(heapTokens);
      return NULL;
    }
  
    // Prepass: Basically we iterate over the tokens once and figure out how much memory we need and
    // record the locations of tokens that we'll use later to fill in the memory once it's allocated.
  
    struct {
      jsmntok_t* animations;
      jsmntok_t* attributes;
      jsmntok_t* buffers;
      jsmntok_t* bufferViews;
      jsmntok_t* images;
      jsmntok_t* materials;
      jsmntok_t* meshes;
      jsmntok_t* nodes;
      jsmntok_t* scenes;
      jsmntok_t* skins;
      int sceneCount;
    } info;
  
    memset(&info, 0, sizeof(info));
  
    gltfAnimationSampler* animationSamplers = NULL;
    gltfMesh* meshes = NULL;
    gltfSampler* samplers = NULL;
    gltfTexture* textures = NULL;
    gltfScene* scenes = NULL;
    int rootScene = 0;
  
    for (jsmntok_t* token = tokens + 1; token < tokens + tokenCount;) {
      gltfString key = NOM_STR(json, token);
  
      if (STR_EQ(key, "accessors")) {
        info.attributes = token;
        model->attributeCount = token->size;
        token += NOM_VALUE(json, token);
  
      } else if (STR_EQ(key, "animations")){
        info.animations = token;
        model->animationCount = token->size;
        size_t samplerCount = 0;
        jsmntok_t* t = token;
        for (int i = (t++)->size; i > 0; i--) {
          if (t->size > 0) {
            for (int k = (t++)->size; k > 0; k--) {
              gltfString key = NOM_STR(json, t);
              if (STR_EQ(key, "channels")) { model->channelCount += t->size; }
              else if (STR_EQ(key, "samplers")) { samplerCount += t->size; }
              else if (STR_EQ(key, "name")) { model->charCount += t->end - t->start + 1; }
              t += NOM_VALUE(json, t);
            }
          }
        }
  
        animationSamplers = malloc(samplerCount * sizeof(gltfAnimationSampler));
        lovrAssert(animationSamplers, "Out of memory");
        gltfAnimationSampler* sampler = animationSamplers;
        for (int i = (token++)->size; i > 0; i--) {
          for (int k = (token++)->size; k > 0; k--) {
            gltfString key = NOM_STR(json, token);
            if (STR_EQ(key, "samplers")) {
              for (int j = (token++)->size; j > 0; j--, sampler++) {
                sampler->input = ~0u;
                sampler->output = ~0u;
                sampler->smoothing = SMOOTH_LINEAR;
                for (int kk = (token++)->size; kk > 0; kk--) {
                  gltfString key = NOM_STR(json, token);
                  if (STR_EQ(key, "input")) { sampler->input = NOM_INT(json, token); }
                  else if (STR_EQ(key, "output")) { sampler->output = NOM_INT(json, token); }
                  else if (STR_EQ(key, "interpolation")) {
                    gltfString smoothing = NOM_STR(json, token);
                    if (STR_EQ(smoothing, "LINEAR")) { sampler->smoothing = SMOOTH_LINEAR; }
                    else if (STR_EQ(smoothing, "STEP")) { sampler->smoothing = SMOOTH_STEP; }
                    else if (STR_EQ(smoothing, "CUBICSPLINE")) { sampler->smoothing = SMOOTH_CUBIC; }
                    else { lovrThrow("Unknown animation sampler interpolation"); }
                  } else {
                    token += NOM_VALUE(json, token);
                  }
                }
              }
            } else {
              token += NOM_VALUE(json, token);
            }
          }
        }
  
      } else if (STR_EQ(key, "buffers")) {
        info.buffers = token;
        model->blobCount = token->size;
        token += NOM_VALUE(json, token);
  
      } else if (STR_EQ(key, "bufferViews")) {
        info.bufferViews = token;
        model->bufferCount = token->size;
        token += NOM_VALUE(json, token);
  
      } else if (STR_EQ(key, "images")) {
        info.images = token;
        model->imageCount = token->size;
        token += NOM_VALUE(json, token);
  
      } else if (STR_EQ(key, "samplers")) {
        samplers = malloc(token->size * sizeof(gltfSampler));
        lovrAssert(samplers, "Out of memory");
        gltfSampler* sampler = samplers;
        for (int i = (token++)->size; i > 0; i--, sampler++) {
          sampler->filter.mode = FILTER_BILINEAR;
          sampler->wrap.s = sampler->wrap.t = sampler->wrap.r = WRAP_REPEAT;
          int min = -1;
          int mag = -1;
  
          for (int k = (token++)->size; k > 0; k--) {
            gltfString key = NOM_STR(json, token);
            if (STR_EQ(key, "minFilter")) { min = NOM_INT(json, token); }
            else if (STR_EQ(key, "magFilter")) { mag = NOM_INT(json, token); }
            else if (STR_EQ(key, "wrapS")) {
              switch (NOM_INT(json, token)) {
                case 33071: sampler->wrap.s = WRAP_CLAMP; break;
                case 33648: sampler->wrap.s = WRAP_MIRRORED_REPEAT; break;
                case 10497: sampler->wrap.s = WRAP_REPEAT; break;
                default: lovrThrow("Unknown sampler wrapS mode for sampler %d", i);
              }
            } else if (STR_EQ(key, "wrapT")) {
              switch (NOM_INT(json, token)) {
                case 33071: sampler->wrap.t = WRAP_CLAMP; break;
                case 33648: sampler->wrap.t = WRAP_MIRRORED_REPEAT; break;
                case 10497: sampler->wrap.t = WRAP_REPEAT; break;
                default: lovrThrow("Unknown sampler wrapT mode for sampler %d", i);
              }
            } else {
              token += NOM_VALUE(json, token);
            }
          }
  
          if (min == 9728 || min == 9984 || min == 9986 || mag == 9728) {
            sampler->filter.mode = FILTER_NEAREST;
          } else {
            switch (min) {
              case 9729: sampler->filter.mode = FILTER_BILINEAR; break;
              case 9985: sampler->filter.mode = FILTER_BILINEAR; break;
              case 9987: sampler->filter.mode = FILTER_TRILINEAR; break;
            }
          }
        }
  
      } else if (STR_EQ(key, "textures")) {
        textures = malloc(token->size * sizeof(gltfTexture));
        lovrAssert(textures, "Out of memory");
        gltfTexture* texture = textures;
        for (int i = (token++)->size; i > 0; i--, texture++) {
          texture->image = ~0u;
          texture->sampler = ~0u;
          for (int k = (token++)->size; k > 0; k--) {
            gltfString key = NOM_STR(json, token);
            if (STR_EQ(key, "source")) {
              texture->image = NOM_INT(json, token);
            } else if (STR_EQ(key, "sampler")) {
              texture->sampler = NOM_INT(json, token);
            } else {
              token += NOM_VALUE(json, token);
            }
          }
          lovrAssert(texture->image != ~0u, "Texture is missing an image (maybe an unsupported extension is used?)");
        }
  
      } else if (STR_EQ(key, "materials")) {
        info.materials = token;
        model->materialCount = token->size;
        for (int i = (token++)->size; i > 0; i--) {
          for (int k = (token++)->size; k > 0; k--) {
            gltfString key = NOM_STR(json, token);
            if (STR_EQ(key, "name")) { model->charCount += token->end - token->start + 1; }
            token += NOM_VALUE(json, token);
          }
        }
  
      } else if (STR_EQ(key, "meshes")) {
        info.meshes = token;
        meshes = malloc(token->size * sizeof(gltfMesh));
        lovrAssert(meshes, "Out of memory");
        gltfMesh* mesh = meshes;
        model->primitiveCount = 0;
        for (int i = (token++)->size; i > 0; i--, mesh++) {
          mesh->primitiveCount = 0;
          for (int k = (token++)->size; k > 0; k--) {
            gltfString key = NOM_STR(json, token);
            if (STR_EQ(key, "primitives")) {
              mesh->primitiveIndex = model->primitiveCount;
              mesh->primitiveCount += token->size;
              model->primitiveCount += token->size;
            }
            token += NOM_VALUE(json, token);
          }
        }
  
      } else if (STR_EQ(key, "nodes")) {
        info.nodes = token;
        model->nodeCount = token->size;
        for (int i = (token++)->size; i > 0; i--) {
          if (token->size > 0) {
            for (int k = (token++)->size; k > 0; k--) {
              gltfString key = NOM_STR(json, token);
              if (STR_EQ(key, "children")) { model->childCount += token->size; }
              else if (STR_EQ(key, "name")) { model->charCount += token->end - token->start + 1; }
              token += NOM_VALUE(json, token);
            }
          }
        }
  
      } else if (STR_EQ(key, "scene")) {
        rootScene = NOM_INT(json, token);
  
      } else if (STR_EQ(key, "scenes")) {
        info.scenes = token;
        info.sceneCount = token->size;
        scenes = malloc(info.sceneCount * sizeof(gltfScene));
        lovrAssert(scenes, "Out of memory");
        gltfScene* scene = scenes;
        for (int i = (token++)->size; i > 0; i--, scene++) {
          for (int k = (token++)->size; k > 0; k--) {
            gltfString key = NOM_STR(json, token);
            if (STR_EQ(key, "nodes")) {
              scene->nodeCount = token->size;
              jsmntok_t* t = token + 1;
              scene->node = NOM_INT(json, t);
            }
            token += NOM_VALUE(json, token);
          }
        }
  
      } else if (STR_EQ(key, "skins")) {
        info.skins = token;
        model->skinCount = token->size;
        for (int i = (token++)->size; i > 0; i--) {
          for (int k = (token++)->size; k > 0; k--) {
            gltfString key = NOM_STR(json, token);
            if (STR_EQ(key, "joints")) { model->jointCount += token->size; }
            token += NOM_VALUE(json, token);
          }
        }
  
      } else {
        token += NOM_VALUE(json, token);
      }
    }
  
    // We only support a single root node, so if there is more than one root node in the scene then
    // we create a fake "super root" node and add all the scene's root nodes as its children.
    if (info.sceneCount > 0 && scenes[rootScene].nodeCount > 1) {
      model->childCount += model->nodeCount;
      model->nodeCount++;
    }
  
    // Allocate memory, then revisit all of the tokens that were recorded during the prepass and write
    // their data into this memory.
    lovrModelDataAllocate(model);
  
    // Blobs
    if (model->blobCount > 0) {
      jsmntok_t* token = info.buffers;
      Blob** blob = model->blobs;
      for (int i = (token++)->size; i > 0; i--, blob++) {
        gltfString uri;
        memset(&uri, 0, sizeof(uri));
        size_t size = 0;
  
        for (int k = (token++)->size; k > 0; k--) {
          gltfString key = NOM_STR(json, token);
          if (STR_EQ(key, "byteLength")) { size = NOM_INT(json, token); }
          else if (STR_EQ(key, "uri")) { uri = NOM_STR(json, token); }
          else { token += NOM_VALUE(json, token); }
        }
  
        if (uri.data) {
          size_t bytesRead;
          if (uri.length >= 5 && !strncmp("data:", uri.data, 5)) {
            void* bufferData = decodeBase64(uri.data, uri.length, size);
            lovrAssert(bufferData, "Could not decode base64 buffer");
            *blob = lovrBlobCreate(bufferData, size, NULL);
          } else {
            lovrAssert(uri.length < maxPathLength, "Buffer filename is too long");
            strncat(filename, uri.data, uri.length);
            *blob = lovrBlobCreate(io(filename, &bytesRead), size, NULL);
            lovrAssert((*blob)->data && bytesRead == size, "Unable to read %s", filename);
            *root = '\0';
          }
        } else {
          lovrAssert(glb, "Buffer is missing URI");
          lovrRetain(source);
          *blob = source;
        }
      }
    }
  
    // Buffers
    if (model->bufferCount > 0) {
      jsmntok_t* token = info.bufferViews;
      ModelBuffer* buffer = model->buffers;
      for (int i = (token++)->size; i > 0; i--, buffer++) {
        size_t offset = 0;
        for (int k = (token++)->size; k > 0; k--) {
          gltfString key = NOM_STR(json, token);
          if (STR_EQ(key, "buffer")) { buffer->data = model->blobs[NOM_INT(json, token)]->data; }
          else if (STR_EQ(key, "byteOffset")) { offset = NOM_INT(json, token); }
          else if (STR_EQ(key, "byteLength")) { buffer->size = NOM_INT(json, token); }
          else if (STR_EQ(key, "byteStride")) { buffer->stride = NOM_INT(json, token); }
          else { token += NOM_VALUE(json, token); }
        }
  
        // If this is the glb binary data, increment the offset to account for the file header
        if (buffer->data && buffer->data == source->data && glb) {
          offset += binOffset;
        }
  
        buffer->data = (char*) buffer->data + offset;
      }
    }
  
    // Attributes
    if (model->attributeCount > 0) {
      jsmntok_t* token = info.attributes;
      ModelAttribute* attribute = model->attributes;
      for (int i = (token++)->size; i > 0; i--, attribute++) {
        for (int k = (token++)->size; k > 0; k--) {
          gltfString key = NOM_STR(json, token);
          if (STR_EQ(key, "bufferView")) { attribute->buffer = NOM_INT(json, token); }
          else if (STR_EQ(key, "count")) { attribute->count = NOM_INT(json, token); }
          else if (STR_EQ(key, "byteOffset")) { attribute->offset = NOM_INT(json, token); }
          else if (STR_EQ(key, "normalized")) { attribute->normalized = NOM_BOOL(json, token); }
          else if (STR_EQ(key, "componentType")) {
            switch (NOM_INT(json, token)) {
              case 5120: attribute->type = I8; break;
              case 5121: attribute->type = U8; break;
              case 5122: attribute->type = I16; break;
              case 5123: attribute->type = U16; break;
              case 5125: attribute->type = U32; break;
              case 5126: attribute->type = F32; break;
              default: break;
            }
          } else if (STR_EQ(key, "type")) {
            gltfString type = NOM_STR(json, token);
            if (STR_EQ(type, "SCALAR")) {
              attribute->components = 1;
            } else if (type.length == 4) {
              attribute->components = type.data[3] - '0';
              attribute->matrix = type.data[0] == 'M';
            }
          } else if (STR_EQ(key, "min") && token->size <= 4) {
            int count = (token++)->size;
            attribute->hasMin = true;
            for (int j = 0; j < count; j++) {
              attribute->min[j] = NOM_FLOAT(json, token);
            }
          } else if (STR_EQ(key, "max") && token->size <= 4) {
            int count = (token++)->size;
            attribute->hasMax = true;
            for (int j = 0; j < count; j++) {
              attribute->max[j] = NOM_FLOAT(json, token);
            }
          } else {
            token += NOM_VALUE(json, token);
          }
        }
      }
    }
  
    // Animations
    if (model->animationCount > 0) {
      int channelIndex = 0;
      int baseSampler = 0;
      jsmntok_t* token = info.animations;
      ModelAnimation* animation = model->animations;
      for (int i = (token++)->size; i > 0; i--, animation++) {
        int samplerCount = 0;
        for (int k = (token++)->size; k > 0; k--) {
          gltfString key = NOM_STR(json, token);
          if (STR_EQ(key, "channels")) {
            animation->channelCount = (token++)->size;
            animation->channels = model->channels + channelIndex;
            channelIndex += animation->channelCount;
            for (uint32_t j = 0; j < animation->channelCount; j++) {
              ModelAnimationChannel* channel = &animation->channels[j];
              ModelAttribute* times = NULL;
              ModelAttribute* data = NULL;
  
              for (int kk = (token++)->size; kk > 0; kk--) {
                gltfString key = NOM_STR(json, token);
                if (STR_EQ(key, "sampler")) {
                  gltfAnimationSampler* sampler = animationSamplers + baseSampler + NOM_INT(json, token);
                  times = &model->attributes[sampler->input];
                  data = &model->attributes[sampler->output];
                  channel->smoothing = sampler->smoothing;
                  channel->keyframeCount = times->count;
                } else if (STR_EQ(key, "target")) {
                  for (int kkk = (token++)->size; kkk > 0; kkk--) {
                    gltfString key = NOM_STR(json, token);
                    if (STR_EQ(key, "node")) { channel->nodeIndex = NOM_INT(json, token); }
                    else if (STR_EQ(key, "path")) {
                      gltfString property = NOM_STR(json, token);
                      if (STR_EQ(property, "translation")) { channel->property = PROP_TRANSLATION; }
                      else if (STR_EQ(property, "rotation")) { channel->property = PROP_ROTATION; }
                      else if (STR_EQ(property, "scale")) { channel->property = PROP_SCALE; }
                      else { lovrThrow("Unknown animation channel property"); }
                    } else {
                      token += NOM_VALUE(json, token);
                    }
                  }
                } else {
                  token += NOM_VALUE(json, token);
                }
              }
  
              lovrAssert(times, "Missing keyframe times");
              lovrAssert(data, "Missing keyframe data");
  
              ModelBuffer* buffer;
              buffer = &model->buffers[times->buffer];
              lovrAssert(times->type == F32 && (buffer->stride == 0 || buffer->stride == sizeof(float)), "Keyframe times must be tightly-packed floats");
              channel->times = (float*) (buffer->data + times->offset);
  
              buffer = &model->buffers[data->buffer];
              uint8_t components = data->components;
              lovrAssert(data->type == F32 && (buffer->stride == 0 || buffer->stride == sizeof(float) * components), "Keyframe data must be tightly-packed floats");
              channel->data = (float*) (buffer->data + data->offset);
  
              animation->duration = MAX(animation->duration, channel->times[channel->keyframeCount - 1]);
            }
          } else if (STR_EQ(key, "samplers")) {
            samplerCount = token->size;
            token += NOM_VALUE(json, token);
          } else if (STR_EQ(key, "name")) {
            gltfString name = NOM_STR(json, token);
            map_set(&model->animationMap, hash64(name.data, name.length), model->animationCount - i);
            memcpy(model->chars, name.data, name.length);
            animation->name = model->chars;
            model->chars += name.length + 1;
          } else {
            token += NOM_VALUE(json, token);
          }
        }
        baseSampler += samplerCount;
      }
    }
  
    // Images
    if (model->imageCount > 0) {
      jsmntok_t* token = info.images;
      Image** image = model->images;
      for (int i = (token++)->size; i > 0; i--, image++) {
        for (int k = (token++)->size; k > 0; k--) {
          gltfString key = NOM_STR(json, token);
          if (STR_EQ(key, "bufferView")) {
            ModelBuffer* buffer = &model->buffers[NOM_INT(json, token)];
            Blob* blob = lovrBlobCreate(buffer->data, buffer->size, NULL);
            *image = lovrImageCreateFromBlob(blob, false);
            blob->data = NULL; // XXX Blob data ownership
            lovrRelease(blob, lovrBlobDestroy);
          } else if (STR_EQ(key, "uri")) {
            size_t size = 0;
            gltfString uri = NOM_STR(json, token);
            lovrAssert(uri.length < 5 || strncmp("data:", uri.data, 5), "Base64 images aren't supported yet");
            lovrAssert(uri.length < maxPathLength, "Image filename is too long");
            strncat(filename, uri.data, uri.length);
            void* data = io(filename, &size);
            lovrAssert(data && size > 0, "Unable to read image from '%s'", filename);
            Blob* blob = lovrBlobCreate(data, size, NULL);
            *image = lovrImageCreateFromBlob(blob, false);
            lovrRelease(blob, lovrBlobDestroy);
            *root = '\0';
          } else {
            token += NOM_VALUE(json, token);
          }
        }
      }
    }
  
    // Materials
    if (model->materialCount > 0) {
      jsmntok_t* token = info.materials;
      ModelMaterial* material = model->materials;
      for (int i = (token++)->size; i > 0; i--, material++) {
        material->scalars[SCALAR_METALNESS] = 1.f;
        material->scalars[SCALAR_ROUGHNESS] = 1.f;
        material->scalars[SCALAR_ALPHA_CUTOFF] = 0.f;
        material->colors[COLOR_DIFFUSE] = (Color) { 1.f, 1.f, 1.f, 1.f };
        material->colors[COLOR_EMISSIVE] = (Color) { 0.f, 0.f, 0.f, 0.f };
        memset(material->images, 0xff, MAX_MATERIAL_TEXTURES * sizeof(uint32_t));
  
        for (int k = (token++)->size; k > 0; k--) {
          gltfString key = NOM_STR(json, token);
          if (STR_EQ(key, "pbrMetallicRoughness")) {
            for (int j = (token++)->size; j > 0; j--) {
              gltfString key = NOM_STR(json, token);
              if (STR_EQ(key, "baseColorFactor")) {
                token++; // Enter array
                material->colors[COLOR_DIFFUSE].r = NOM_FLOAT(json, token);
                material->colors[COLOR_DIFFUSE].g = NOM_FLOAT(json, token);
                material->colors[COLOR_DIFFUSE].b = NOM_FLOAT(json, token);
                material->colors[COLOR_DIFFUSE].a = NOM_FLOAT(json, token);
              } else if (STR_EQ(key, "baseColorTexture")) {
                token = resolveTexture(json, token, material, TEXTURE_DIFFUSE, textures, samplers);
              } else if (STR_EQ(key, "metallicFactor")) {
                material->scalars[SCALAR_METALNESS] = NOM_FLOAT(json, token);
              } else if (STR_EQ(key, "roughnessFactor")) {
                material->scalars[SCALAR_ROUGHNESS] = NOM_FLOAT(json, token);
              } else if (STR_EQ(key, "metallicRoughnessTexture")) {
                token = resolveTexture(json, token, material, TEXTURE_METALNESS, textures, samplers);
                material->images[TEXTURE_ROUGHNESS] = material->images[TEXTURE_METALNESS];
                material->filters[TEXTURE_ROUGHNESS] = material->filters[TEXTURE_METALNESS];
                material->wraps[TEXTURE_ROUGHNESS] = material->wraps[TEXTURE_METALNESS];
              } else {
                token += NOM_VALUE(json, token);
              }
            }
          } else if (STR_EQ(key, "normalTexture")) {
            token = resolveTexture(json, token, material, TEXTURE_NORMAL, textures, samplers);
          } else if (STR_EQ(key, "occlusionTexture")) {
            token = resolveTexture(json, token, material, TEXTURE_OCCLUSION, textures, samplers);
          } else if (STR_EQ(key, "emissiveTexture")) {
            token = resolveTexture(json, token, material, TEXTURE_EMISSIVE, textures, samplers);
          } else if (STR_EQ(key, "emissiveFactor")) {
            token++; // Enter array
            material->colors[COLOR_EMISSIVE].r = NOM_FLOAT(json, token);
            material->colors[COLOR_EMISSIVE].g = NOM_FLOAT(json, token);
            material->colors[COLOR_EMISSIVE].b = NOM_FLOAT(json, token);
          } else if (STR_EQ(key, "alphaCutoff")) {
            material->scalars[SCALAR_ALPHA_CUTOFF] = NOM_FLOAT(json, token);
          } else if (STR_EQ(key, "name")) {
            gltfString name = NOM_STR(json, token);
            map_set(&model->materialMap, hash64(name.data, name.length), model->materialCount - i);
            memcpy(model->chars, name.data, name.length);
            material->name = model->chars;
            model->chars += name.length + 1;
          } else {
            token += NOM_VALUE(json, token);
          }
        }
      }
    }
  
    // Primitives
    if (model->primitiveCount > 0) {
      jsmntok_t* token = info.meshes;
      ModelPrimitive* primitive = model->primitives;
      for (int i = (token++)->size; i > 0; i--) {
        for (int k = (token++)->size; k > 0; k--) {
          gltfString key = NOM_STR(json, token);
          if (STR_EQ(key, "primitives")) {
            for (uint32_t j = (token++)->size; j > 0; j--, primitive++) {
              primitive->mode = DRAW_TRIANGLES;
              primitive->material = ~0u;
  
              for (int kk = (token++)->size; kk > 0; kk--) {
                gltfString key = NOM_STR(json, token);
                if (STR_EQ(key, "material")) {
                  primitive->material = NOM_INT(json, token);
                } else if (STR_EQ(key, "indices")) {
                  primitive->indices = &model->attributes[NOM_INT(json, token)];
                  lovrAssert(primitive->indices->type != U8, "Unsigned byte indices are not supported (must be unsigned shorts or unsigned ints)");
                } else if (STR_EQ(key, "mode")) {
                  switch (NOM_INT(json, token)) {
                    case 0: primitive->mode = DRAW_POINTS; break;
                    case 1: primitive->mode = DRAW_LINES; break;
                    case 2: primitive->mode = DRAW_LINE_LOOP; break;
                    case 3: primitive->mode = DRAW_LINE_STRIP; break;
                    case 4: primitive->mode = DRAW_TRIANGLES; break;
                    case 5: primitive->mode = DRAW_TRIANGLE_STRIP; break;
                    case 6: primitive->mode = DRAW_TRIANGLE_FAN; break;
                    default: lovrThrow("Unknown primitive mode");
                  }
                } else if (STR_EQ(key, "attributes")) {
                  int attributeCount = (token++)->size;
                  for (int a = 0; a < attributeCount; a++) {
                    DefaultAttribute attributeType = ~0;
                    gltfString name = NOM_STR(json, token);
                    uint32_t attributeIndex = NOM_INT(json, token);
                    if (STR_EQ(name, "POSITION")) { attributeType = ATTR_POSITION; }
                    else if (STR_EQ(name, "NORMAL")) { attributeType = ATTR_NORMAL; }
                    else if (STR_EQ(name, "TEXCOORD_0")) { attributeType = ATTR_TEXCOORD; }
                    else if (STR_EQ(name, "COLOR_0")) { attributeType = ATTR_COLOR; }
                    else if (STR_EQ(name, "TANGENT")) { attributeType = ATTR_TANGENT; }
                    else if (STR_EQ(name, "JOINTS_0")) { attributeType = ATTR_BONES; }
                    else if (STR_EQ(name, "WEIGHTS_0")) { attributeType = ATTR_WEIGHTS; }
                    if (attributeType != (DefaultAttribute) ~0) {
                      primitive->attributes[attributeType] = &model->attributes[attributeIndex];
                    }
                  }
                } else {
                  token += NOM_VALUE(json, token);
                }
              }
            }
          } else {
            token += NOM_VALUE(json, token);
          }
        }
      }
    }
  
    // Nodes
    uint32_t childIndex = 0;
    if (model->nodeCount > 0) {
      jsmntok_t* token = info.nodes;
      ModelNode* node = model->nodes;
      for (int i = (token++)->size; i > 0; i--, node++) {
        vec3 translation = vec3_set(node->transform.properties.translation, 0.f, 0.f, 0.f);
        quat rotation = quat_set(node->transform.properties.rotation, 0.f, 0.f, 0.f, 1.f);
        vec3 scale = vec3_set(node->transform.properties.scale, 1.f, 1.f, 1.f);
        node->matrix = false;
        node->primitiveCount = 0;
        node->skin = ~0u;
  
        for (int k = (token++)->size; k > 0; k--) {
          gltfString key = NOM_STR(json, token);
          if (STR_EQ(key, "mesh")) {
            gltfMesh* mesh = &meshes[NOM_INT(json, token)];
            node->primitiveIndex = mesh->primitiveIndex;
            node->primitiveCount = mesh->primitiveCount;
          } else if (STR_EQ(key, "skin")) {
            node->skin = NOM_INT(json, token);
          } else if (STR_EQ(key, "children")) {
            node->children = &model->children[childIndex];
            node->childCount = (token++)->size;
            for (uint32_t j = 0; j < node->childCount; j++) {
              model->children[childIndex++] = NOM_INT(json, token);
            }
          } else if (STR_EQ(key, "matrix")) {
            lovrAssert((token++)->size == 16, "Node matrix needs 16 elements");
            node->matrix = true;
            for (int j = 0; j < 16; j++) {
              node->transform.matrix[j] = NOM_FLOAT(json, token);
            }
          } else if (STR_EQ(key, "translation")) {
            lovrAssert((token++)->size == 3, "Node translation needs 3 elements");
            translation[0] = NOM_FLOAT(json, token);
            translation[1] = NOM_FLOAT(json, token);
            translation[2] = NOM_FLOAT(json, token);
          } else if (STR_EQ(key, "rotation")) {
            lovrAssert((token++)->size == 4, "Node rotation needs 4 elements");
            rotation[0] = NOM_FLOAT(json, token);
            rotation[1] = NOM_FLOAT(json, token);
            rotation[2] = NOM_FLOAT(json, token);
            rotation[3] = NOM_FLOAT(json, token);
          } else if (STR_EQ(key, "scale")) {
            lovrAssert((token++)->size == 3, "Node scale needs 3 elements");
            scale[0] = NOM_FLOAT(json, token);
            scale[1] = NOM_FLOAT(json, token);
            scale[2] = NOM_FLOAT(json, token);
          } else if (STR_EQ(key, "name")) {
            gltfString name = NOM_STR(json, token);
            map_set(&model->nodeMap, hash64(name.data, name.length), model->nodeCount - i);
            memcpy(model->chars, name.data, name.length);
            node->name = model->chars;
            model->chars += name.length + 1;
          } else {
            token += NOM_VALUE(json, token);
          }
        }
      }
    }
  
    // Skins
    if (model->skinCount > 0) {
      int jointIndex = 0;
      jsmntok_t* token = info.skins;
      ModelSkin* skin = model->skins;
      for (int i = (token++)->size; i > 0; i--, skin++) {
        for (int k = (token++)->size; k > 0; k--) {
          gltfString key = NOM_STR(json, token);
          if (STR_EQ(key, "inverseBindMatrices")) {
            ModelAttribute* attribute = &model->attributes[NOM_INT(json, token)];
            ModelBuffer* buffer = &model->buffers[attribute->buffer];
            skin->inverseBindMatrices = (float*) ((uint8_t*) buffer->data + attribute->offset);
          } else if (STR_EQ(key, "joints")) {
            skin->joints = &model->joints[jointIndex];
            skin->jointCount = (token++)->size;
            for (uint32_t j = 0; j < skin->jointCount; j++) {
              model->joints[jointIndex++] = NOM_INT(json, token);
            }
          } else {
            token += NOM_VALUE(json, token);
          }
        }
      }
    }
  
    // Scenes
    if (info.sceneCount == 0) {
      model->rootNode = 0;
    } else if (scenes[rootScene].nodeCount > 1) {
      model->rootNode = model->nodeCount - 1;
      ModelNode* lastNode = &model->nodes[model->rootNode];
      lastNode->childCount = scenes[rootScene].nodeCount;
      lastNode->children = &model->children[childIndex];
      mat4_identity(lastNode->transform.matrix);
      lastNode->matrix = true;
      lastNode->primitiveCount = 0;
      lastNode->skin = ~0u;
  
      jsmntok_t* token = info.scenes;
      int sceneCount = (token++)->size;
      for (int i = 0; i < sceneCount; i++) {
        if (i == rootScene) {
          for (int k = (token++)->size; k > 0; k--) {
            gltfString key = NOM_STR(json, token);
            if (STR_EQ(key, "nodes")) {
              for (int j = (token++)->size; j > 0; j--) {
                lastNode->children[lastNode->childCount - j] = NOM_INT(json, token);
              }
            } else {
              token += NOM_VALUE(json, token);
            }
          }
        } else {
          token += NOM_VALUE(json, token);
        }
      }
    } else {
      model->rootNode = scenes[rootScene].node;
    }
  
    free(animationSamplers);
    free(meshes);
    free(samplers);
    free(textures);
    free(scenes);
    free(heapTokens);
    return model;
  }
  