VideoCommon: add functionality to prepare for a mesh asset that is loaded from a GLTF file

Source/Core/DolphinLib.props

@@ -656,6 +656,7 @@
     <ClInclude Include="VideoCommon\Assets\CustomTextureData.h" />
     <ClInclude Include="VideoCommon\Assets\DirectFilesystemAssetLibrary.h" />
     <ClInclude Include="VideoCommon\Assets\MaterialAsset.h" />
+    <ClInclude Include="VideoCommon\Assets\MeshAsset.h" />
     <ClInclude Include="VideoCommon\Assets\ShaderAsset.h" />
     <ClInclude Include="VideoCommon\Assets\TextureAsset.h" />
     <ClInclude Include="VideoCommon\AsyncRequests.h" />
@@ -1293,6 +1294,7 @@
     <ClCompile Include="VideoCommon\Assets\CustomTextureData.cpp" />
     <ClCompile Include="VideoCommon\Assets\DirectFilesystemAssetLibrary.cpp" />
     <ClCompile Include="VideoCommon\Assets\MaterialAsset.cpp" />
+    <ClCompile Include="VideoCommon\Assets\MeshAsset.cpp" />
     <ClCompile Include="VideoCommon\Assets\ShaderAsset.cpp" />
     <ClCompile Include="VideoCommon\Assets\TextureAsset.cpp" />
     <ClCompile Include="VideoCommon\AsyncRequests.cpp" />

Source/Core/VideoCommon/Assets/MeshAsset.cpp

@@ -0,0 +1,648 @@
+// Copyright 2023 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "VideoCommon/Assets/MeshAsset.h"
+
+#include <algorithm>
+#include <array>
+#include <utility>
+
+#include <tinygltf/tiny_gltf.h>
+
+#include "Common/IOFile.h"
+#include "Common/Logging/Log.h"
+#include "Common/StringUtil.h"
+
+namespace VideoCommon
+{
+namespace
+{
+Common::Matrix44 BuildMatrixFromNode(const tinygltf::Node& node)
+{
+  if (!node.matrix.empty())
+  {
+    Common::Matrix44 matrix;
+    for (std::size_t i = 0; i < node.matrix.size(); i++)
+    {
+      matrix.data[i] = static_cast<float>(node.matrix[i]);
+    }
+    return matrix;
+  }
+
+  Common::Matrix44 matrix = Common::Matrix44::Identity();
+
+  // Check individual components
+
+  if (!node.scale.empty())
+  {
+    matrix *= Common::Matrix44::FromMatrix33(Common::Matrix33::Scale(
+        Common::Vec3{static_cast<float>(node.scale[0]), static_cast<float>(node.scale[1]),
+                     static_cast<float>(node.scale[2])}));
+  }
+
+  if (!node.rotation.empty())
+  {
+    matrix *= Common::Matrix44::FromQuaternion(Common::Quaternion(
+        static_cast<float>(node.rotation[3]), static_cast<float>(node.rotation[0]),
+        static_cast<float>(node.rotation[1]), static_cast<float>(node.rotation[2])));
+  }
+
+  if (!node.translation.empty())
+  {
+    matrix *= Common::Matrix44::Translate(Common::Vec3{static_cast<float>(node.translation[0]),
+                                                       static_cast<float>(node.translation[1]),
+                                                       static_cast<float>(node.translation[2])});
+  }
+
+  return matrix;
+}
+
+bool GLTFComponentTypeToAttributeFormat(int component_type, AttributeFormat* format)
+{
+  switch (component_type)
+  {
+  case TINYGLTF_COMPONENT_TYPE_BYTE:
+  {
+    format->type = ComponentFormat::Byte;
+    format->integer = false;
+  }
+  break;
+  case TINYGLTF_COMPONENT_TYPE_DOUBLE:
+  {
+    return false;
+  }
+  break;
+  case TINYGLTF_COMPONENT_TYPE_FLOAT:
+  {
+    format->type = ComponentFormat::Float;
+    format->integer = false;
+  }
+  break;
+  case TINYGLTF_COMPONENT_TYPE_INT:
+  {
+    format->type = ComponentFormat::Float;
+    format->integer = true;
+  }
+  break;
+  case TINYGLTF_COMPONENT_TYPE_SHORT:
+  {
+    format->type = ComponentFormat::Short;
+    format->integer = false;
+  }
+  break;
+  case TINYGLTF_COMPONENT_TYPE_UNSIGNED_BYTE:
+  {
+    format->type = ComponentFormat::UByte;
+    format->integer = false;
+  }
+  break;
+  case TINYGLTF_COMPONENT_TYPE_UNSIGNED_INT:
+  {
+    return false;
+  }
+  break;
+  case TINYGLTF_COMPONENT_TYPE_UNSIGNED_SHORT:
+  {
+    format->type = ComponentFormat::UShort;
+    format->integer = false;
+  }
+  break;
+  };
+
+  return true;
+}
+
+bool UpdateVertexStrideFromPrimitive(const tinygltf::Model& model, u32 accessor_index,
+                                     MeshDataChunk* chunk)
+{
+  const tinygltf::Accessor& accessor = model.accessors[accessor_index];
+
+  const int component_count = tinygltf::GetNumComponentsInType(accessor.type);
+  if (component_count == -1)
+  {
+    ERROR_LOG_FMT(VIDEO, "Failed to update vertex stride, component count was invalid");
+    return false;
+  }
+
+  const int component_size =
+      tinygltf::GetComponentSizeInBytes(static_cast<uint32_t>(accessor.componentType));
+  if (component_size == -1)
+  {
+    ERROR_LOG_FMT(VIDEO, "Failed to update vertex stride, component size was invalid");
+    return false;
+  }
+
+  chunk->vertex_stride += component_size * component_count;
+  return true;
+}
+
+bool CopyBufferDataFromPrimitive(const tinygltf::Model& model, u32 accessor_index,
+                                 std::size_t* outbound_offset, MeshDataChunk* chunk)
+{
+  const tinygltf::Accessor& accessor = model.accessors[accessor_index];
+
+  const int component_count = tinygltf::GetNumComponentsInType(accessor.type);
+  if (component_count == -1)
+  {
+    ERROR_LOG_FMT(VIDEO, "Failed to copy buffer data from primitive, component count was invalid");
+    return false;
+  }
+
+  const int component_size =
+      tinygltf::GetComponentSizeInBytes(static_cast<uint32_t>(accessor.componentType));
+  if (component_size == -1)
+  {
+    ERROR_LOG_FMT(VIDEO, "Failed to copy buffer data from primitive, component size was invalid");
+    return false;
+  }
+
+  const tinygltf::BufferView& buffer_view = model.bufferViews[accessor.bufferView];
+  const tinygltf::Buffer& buffer = model.buffers[buffer_view.buffer];
+
+  if (buffer_view.byteStride == 0)
+  {
+    // Data is tightly packed
+    const auto data = &buffer.data[accessor.byteOffset + buffer_view.byteOffset];
+    for (std::size_t i = 0; i < accessor.count; i++)
+    {
+      const std::size_t vertex_data_offset = i * chunk->vertex_stride + *outbound_offset;
+      memcpy(&chunk->vertex_data[vertex_data_offset], &data[i * component_size * component_count],
+             component_size * component_count);
+    }
+  }
+  else
+  {
+    // Data is interleaved
+    const auto data = &buffer.data[accessor.byteOffset + buffer_view.byteOffset];
+    for (std::size_t i = 0; i < accessor.count; i++)
+    {
+      const std::size_t vertex_data_offset = i * chunk->vertex_stride + *outbound_offset;
+      const std::size_t gltf_data_offset = i * buffer_view.byteStride;
+
+      memcpy(&chunk->vertex_data[vertex_data_offset], &data[gltf_data_offset],
+             component_size * component_count);
+    }
+  }
+
+  *outbound_offset += component_size * component_count;
+
+  return true;
+}
+
+bool ReadGLTFMesh(std::string_view mesh_file, const tinygltf::Model& model,
+                  const tinygltf::Mesh& mesh, const Common::Matrix44& mat, MeshData* data)
+{
+  for (std::size_t primitive_index = 0; primitive_index < mesh.primitives.size(); ++primitive_index)
+  {
+    MeshDataChunk chunk;
+    chunk.transform = mat;
+    const tinygltf::Primitive& primitive = mesh.primitives[primitive_index];
+    if (primitive.indices == -1)
+    {
+      ERROR_LOG_FMT(VIDEO, "Mesh '{}' is expected to have indices but doesn't have any", mesh_file);
+      return false;
+    }
+    chunk.material_name = model.materials[primitive.material].name;
+    const tinygltf::Accessor& index_accessor = model.accessors[primitive.indices];
+    const tinygltf::BufferView& index_buffer_view = model.bufferViews[index_accessor.bufferView];
+    const tinygltf::Buffer& index_buffer = model.buffers[index_buffer_view.buffer];
+    const int index_stride = index_accessor.ByteStride(index_buffer_view);
+    if (index_stride == -1)
+    {
+      ERROR_LOG_FMT(VIDEO, "Mesh '{}' has invalid stride", mesh_file);
+      return false;
+    }
+    // TODO C++23: use make_unique_overwrite
+    chunk.indices = std::unique_ptr<u16[]>(new u16[index_accessor.count]);
+    auto index_src = &index_buffer.data[index_accessor.byteOffset + index_buffer_view.byteOffset];
+    for (std::size_t i = 0; i < index_accessor.count; i++)
+    {
+      if (index_accessor.componentType == TINYGLTF_COMPONENT_TYPE_UNSIGNED_SHORT)
+      {
+        std::memcpy(&chunk.indices[i], &index_src[i * index_stride], sizeof(u16));
+      }
+      else if (index_accessor.componentType == TINYGLTF_COMPONENT_TYPE_UNSIGNED_BYTE)
+      {
+        u8 unsigned_byte;
+        std::memcpy(&unsigned_byte, &index_src[i * index_stride], sizeof(u8));
+        chunk.indices[i] = unsigned_byte;
+      }
+      else if (index_accessor.componentType == TINYGLTF_COMPONENT_TYPE_UNSIGNED_INT)
+      {
+        // TODO: update Dolphin to support u32 indices
+        ERROR_LOG_FMT(
+            VIDEO,
+            "Mesh '{}' uses an indice format of unsigned int which is not currently supported",
+            mesh_file);
+        return false;
+      }
+    }
+
+    chunk.num_indices = static_cast<u32>(index_accessor.count);
+
+    if (primitive.mode == TINYGLTF_MODE_TRIANGLES)
+    {
+      chunk.primitive_type = PrimitiveType::Triangles;
+    }
+    else if (primitive.mode == TINYGLTF_MODE_TRIANGLE_STRIP)
+    {
+      chunk.primitive_type = PrimitiveType::TriangleStrip;
+    }
+    else if (primitive.mode == TINYGLTF_MODE_TRIANGLE_FAN)
+    {
+      ERROR_LOG_FMT(VIDEO, "Mesh '{}' requires triangle fan but that is not supported", mesh_file);
+      return false;
+    }
+    else if (primitive.mode == TINYGLTF_MODE_LINE)
+    {
+      chunk.primitive_type = PrimitiveType::Lines;
+    }
+    else if (primitive.mode == TINYGLTF_MODE_POINTS)
+    {
+      chunk.primitive_type = PrimitiveType::Points;
+    }
+
+    chunk.vertex_stride = 0;
+    static constexpr std::array<std::string_view, 12> all_names = {
+        "POSITION",   "NORMAL",     "COLOR_0",    "COLOR_1",    "TEXCOORD_0", "TEXCOORD_1",
+        "TEXCOORD_2", "TEXCOORD_3", "TEXCOORD_4", "TEXCOORD_5", "TEXCOORD_6", "TEXCOORD_7",
+    };
+    for (std::size_t i = 0; i < all_names.size(); i++)
+    {
+      const auto it = primitive.attributes.find(std::string{all_names[i]});
+      if (it != primitive.attributes.end())
+      {
+        if (!UpdateVertexStrideFromPrimitive(model, it->second, &chunk))
+          return false;
+      }
+    }
+    chunk.vertex_declaration.stride = chunk.vertex_stride;
+
+    const auto position_it = primitive.attributes.find("POSITION");
+    if (position_it == primitive.attributes.end())
+    {
+      ERROR_LOG_FMT(VIDEO, "Mesh '{}' does not provide a POSITION attribute, that is required",
+                    mesh_file);
+      return false;
+    }
+    std::size_t outbound_offset = 0;
+    const tinygltf::Accessor& pos_accessor = model.accessors[position_it->second];
+    chunk.num_vertices = static_cast<u32>(pos_accessor.count);
+    // TODO C++23: use make_unique_overwrite
+    chunk.vertex_data = std::unique_ptr<u8[]>(new u8[chunk.num_vertices * chunk.vertex_stride]);
+    if (!CopyBufferDataFromPrimitive(model, position_it->second, &outbound_offset, &chunk))
+      return false;
+    chunk.components_available = 0;
+    chunk.vertex_declaration.position.enable = true;
+    chunk.vertex_declaration.position.components = 3;
+    chunk.vertex_declaration.position.offset = 0;
+    if (!GLTFComponentTypeToAttributeFormat(pos_accessor.componentType,
+                                            &chunk.vertex_declaration.position))
+    {
+      ERROR_LOG_FMT(VIDEO, "Mesh '{}' has invalid attribute format for position", mesh_file);
+      return false;
+    }
+
+    // Save off min and max position in case we want to compute bounds
+    // GLTF spec expects these values to exist but error if they don't
+    if (pos_accessor.minValues.size() != 3)
+    {
+      ERROR_LOG_FMT(VIDEO, "Mesh '{}' is expected to have a minimum value but it is missing",
+                    mesh_file);
+      return false;
+    }
+    chunk.minimum_position.x = static_cast<float>(pos_accessor.minValues[0]);
+    chunk.minimum_position.y = static_cast<float>(pos_accessor.minValues[1]);
+    chunk.minimum_position.z = static_cast<float>(pos_accessor.minValues[2]);
+
+    if (pos_accessor.maxValues.size() != 3)
+    {
+      ERROR_LOG_FMT(VIDEO, "Mesh '{}' is expected to have a maximum value but it is missing",
+                    mesh_file);
+      return false;
+    }
+    chunk.maximum_position.x = static_cast<float>(pos_accessor.maxValues[0]);
+    chunk.maximum_position.y = static_cast<float>(pos_accessor.maxValues[1]);
+    chunk.maximum_position.z = static_cast<float>(pos_accessor.maxValues[2]);
+
+    static constexpr std::array<std::string_view, 2> color_names = {
+        "COLOR_0",
+        "COLOR_1",
+    };
+    for (std::size_t i = 0; i < color_names.size(); i++)
+    {
+      const auto color_it = primitive.attributes.find(std::string{color_names[i]});
+      if (color_it != primitive.attributes.end())
+      {
+        chunk.vertex_declaration.colors[i].offset = static_cast<int>(outbound_offset);
+        if (!CopyBufferDataFromPrimitive(model, color_it->second, &outbound_offset, &chunk))
+          return false;
+        chunk.components_available |= VB_HAS_COL0 << i;
+
+        chunk.vertex_declaration.colors[i].enable = true;
+        chunk.vertex_declaration.colors[i].components = 3;
+        const tinygltf::Accessor& accessor = model.accessors[color_it->second];
+        if (!GLTFComponentTypeToAttributeFormat(accessor.componentType,
+                                                &chunk.vertex_declaration.colors[i]))
+        {
+          ERROR_LOG_FMT(VIDEO, "Mesh '{}' has invalid attribute format for {}", mesh_file,
+                        color_names[i]);
+          return false;
+        }
+      }
+      else
+      {
+        chunk.vertex_declaration.colors[i].enable = false;
+      }
+    }
+
+    const auto normal_it = primitive.attributes.find("NORMAL");
+    if (normal_it != primitive.attributes.end())
+    {
+      chunk.vertex_declaration.normals[0].offset = static_cast<int>(outbound_offset);
+      if (!CopyBufferDataFromPrimitive(model, normal_it->second, &outbound_offset, &chunk))
+        return false;
+      chunk.components_available |= VB_HAS_NORMAL;
+      chunk.vertex_declaration.normals[0].enable = true;
+      chunk.vertex_declaration.normals[0].components = 3;
+      const tinygltf::Accessor& accessor = model.accessors[normal_it->second];
+      if (!GLTFComponentTypeToAttributeFormat(accessor.componentType,
+                                              &chunk.vertex_declaration.normals[0]))
+      {
+        ERROR_LOG_FMT(VIDEO, "Mesh '{}' has invalid attribute format for NORMAL", mesh_file);
+        return false;
+      }
+    }
+    else
+    {
+      chunk.vertex_declaration.normals[0].enable = false;
+    }
+
+    static constexpr std::array<std::string_view, 8> texcoord_names = {
+        "TEXCOORD_0", "TEXCOORD_1", "TEXCOORD_2", "TEXCOORD_3",
+        "TEXCOORD_4", "TEXCOORD_5", "TEXCOORD_6", "TEXCOORD_7",
+    };
+    for (std::size_t i = 0; i < texcoord_names.size(); i++)
+    {
+      const auto texture_it = primitive.attributes.find(std::string{texcoord_names[i]});
+      if (texture_it != primitive.attributes.end())
+      {
+        chunk.vertex_declaration.texcoords[i].offset = static_cast<int>(outbound_offset);
+        if (!CopyBufferDataFromPrimitive(model, texture_it->second, &outbound_offset, &chunk))
+          return false;
+        chunk.components_available |= VB_HAS_UV0 << i;
+        chunk.vertex_declaration.texcoords[i].enable = true;
+        chunk.vertex_declaration.texcoords[i].components = 2;
+        const tinygltf::Accessor& accessor = model.accessors[texture_it->second];
+        if (!GLTFComponentTypeToAttributeFormat(accessor.componentType,
+                                                &chunk.vertex_declaration.texcoords[i]))
+        {
+          ERROR_LOG_FMT(VIDEO, "Mesh '{}' has invalid attribute format for {}", mesh_file,
+                        texcoord_names[i]);
+          return false;
+        }
+      }
+      else
+      {
+        chunk.vertex_declaration.texcoords[i].enable = false;
+      }
+    }
+
+    // Position matrix can be enabled if the draw that is using
+    // this mesh needs it
+    chunk.vertex_declaration.posmtx.enable = false;
+
+    data->m_mesh_chunks.push_back(std::move(chunk));
+  }
+
+  return true;
+}
+
+bool ReadGLTFNodes(std::string_view mesh_file, const tinygltf::Model& model,
+                   const tinygltf::Node& node, const Common::Matrix44& mat, MeshData* data)
+{
+  if (node.mesh != -1)
+  {
+    if (!ReadGLTFMesh(mesh_file, model, model.meshes[node.mesh], mat, data))
+      return false;
+  }
+
+  for (std::size_t i = 0; i < node.children.size(); i++)
+  {
+    const tinygltf::Node& child = model.nodes[node.children[i]];
+    const auto child_mat = mat * BuildMatrixFromNode(child);
+    if (!ReadGLTFNodes(mesh_file, model, child, child_mat, data))
+      return false;
+  }
+
+  return true;
+}
+
+bool ReadGLTFMaterials(std::string_view mesh_file, const tinygltf::Model& model, MeshData* data)
+{
+  for (std::size_t i = 0; i < model.materials.size(); i++)
+  {
+    const tinygltf::Material& material = model.materials[i];
+
+    // TODO: support converting material data into Dolphin material assets
+    data->m_mesh_material_to_material_asset_id.insert_or_assign(material.name, "");
+  }
+
+  return true;
+}
+
+bool ReadGLTF(std::string_view mesh_file, const tinygltf::Model& model, MeshData* data)
+{
+  int scene_index = model.defaultScene;
+  if (scene_index == -1)
+    scene_index = 0;
+
+  const auto& scene = model.scenes[scene_index];
+  const auto scene_node_indices = scene.nodes;
+  for (std::size_t i = 0; i < scene_node_indices.size(); i++)
+  {
+    const tinygltf::Node& node = model.nodes[scene_node_indices[i]];
+    const auto mat = BuildMatrixFromNode(node);
+    if (!ReadGLTFNodes(mesh_file, model, node, mat, data))
+      return false;
+  }
+
+  return ReadGLTFMaterials(mesh_file, model, data);
+}
+}  // namespace
+bool MeshData::FromJson(const VideoCommon::CustomAssetLibrary::AssetID& asset_id,
+                        const picojson::object& json, MeshData* data)
+{
+  if (const auto iter = json.find("material_mapping"); iter != json.end())
+  {
+    if (!iter->second.is<picojson::object>())
+    {
+      ERROR_LOG_FMT(
+          VIDEO,
+          "Asset '{}' failed to parse json, expected 'material_mapping' to be of type object",
+          asset_id);
+      return false;
+    }
+
+    for (const auto& [material_name, asset_id_json] : iter->second.get<picojson::object>())
+    {
+      if (!asset_id_json.is<std::string>())
+      {
+        ERROR_LOG_FMT(
+            VIDEO,
+            "Asset '{}' failed to parse json, material name '{}' linked to a non-string value",
+            asset_id, material_name);
+        return false;
+      }
+
+      data->m_mesh_material_to_material_asset_id[material_name] = asset_id_json.to_str();
+    }
+  }
+  return true;
+}
+
+void MeshData::ToJson(picojson::object& obj, const MeshData& data)
+{
+  picojson::object material_mapping;
+  for (const auto& [material_name, asset_id] : data.m_mesh_material_to_material_asset_id)
+  {
+    material_mapping.emplace(material_name, asset_id);
+  }
+  obj.emplace("material_mapping", std::move(material_mapping));
+}
+
+bool MeshData::FromDolphinMesh(std::span<const u8> raw_data, MeshData* data)
+{
+  std::size_t offset = 0;
+
+  std::size_t chunk_size = 0;
+  std::memcpy(&chunk_size, raw_data.data(), sizeof(std::size_t));
+  offset += sizeof(std::size_t);
+
+  data->m_mesh_chunks.reserve(chunk_size);
+  for (std::size_t i = 0; i < chunk_size; i++)
+  {
+    MeshDataChunk chunk;
+
+    std::memcpy(&chunk.num_vertices, raw_data.data() + offset, sizeof(u32));
+    offset += sizeof(u32);
+
+    std::memcpy(&chunk.vertex_stride, raw_data.data() + offset, sizeof(u32));
+    offset += sizeof(u32);
+
+    // TODO C++23: use make_unique_overwrite
+    chunk.vertex_data = std::unique_ptr<u8[]>(new u8[chunk.num_vertices * chunk.vertex_stride]);
+    std::memcpy(chunk.vertex_data.get(), raw_data.data() + offset,
+                chunk.num_vertices * chunk.vertex_stride);
+    offset += chunk.num_vertices * chunk.vertex_stride;
+
+    std::memcpy(&chunk.num_indices, raw_data.data() + offset, sizeof(u32));
+    offset += sizeof(u32);
+
+    // TODO C++23: use make_unique_overwrite
+    chunk.indices = std::unique_ptr<u16[]>(new u16[chunk.num_indices]);
+    std::memcpy(chunk.indices.get(), raw_data.data() + offset, chunk.num_indices * sizeof(u16));
+    offset += chunk.num_indices * sizeof(u16);
+
+    std::memcpy(&chunk.vertex_declaration, raw_data.data() + offset,
+                sizeof(PortableVertexDeclaration));
+    offset += sizeof(PortableVertexDeclaration);
+
+    std::memcpy(&chunk.primitive_type, raw_data.data() + offset, sizeof(PrimitiveType));
+    offset += sizeof(PrimitiveType);
+
+    std::memcpy(&chunk.components_available, raw_data.data() + offset, sizeof(u32));
+    offset += sizeof(u32);
+
+    std::memcpy(&chunk.minimum_position, raw_data.data() + offset, sizeof(Common::Vec3));
+    offset += sizeof(Common::Vec3);
+
+    std::memcpy(&chunk.maximum_position, raw_data.data() + offset, sizeof(Common::Vec3));
+    offset += sizeof(Common::Vec3);
+
+    std::memcpy(&chunk.transform.data[0], raw_data.data() + offset,
+                chunk.transform.data.size() * sizeof(float));
+    offset += chunk.transform.data.size() * sizeof(float);
+
+    std::size_t material_name_size = 0;
+    std::memcpy(&material_name_size, raw_data.data() + offset, sizeof(std::size_t));
+    offset += sizeof(std::size_t);
+
+    chunk.material_name.assign(raw_data.data() + offset,
+                               raw_data.data() + offset + material_name_size);
+    offset += material_name_size * sizeof(char);
+
+    data->m_mesh_chunks.push_back(std::move(chunk));
+  }
+
+  return true;
+}
+
+bool MeshData::ToDolphinMesh(File::IOFile* file_data, const MeshData& data)
+{
+  const std::size_t chunk_size = data.m_mesh_chunks.size();
+  file_data->WriteBytes(&chunk_size, sizeof(std::size_t));
+  for (const auto& chunk : data.m_mesh_chunks)
+  {
+    if (!file_data->WriteBytes(&chunk.num_vertices, sizeof(u32)))
+      return false;
+    if (!file_data->WriteBytes(&chunk.vertex_stride, sizeof(u32)))
+      return false;
+    if (!file_data->WriteBytes(chunk.vertex_data.get(), chunk.num_vertices * chunk.vertex_stride))
+      return false;
+    if (!file_data->WriteBytes(&chunk.num_indices, sizeof(u32)))
+      return false;
+    if (!file_data->WriteBytes(chunk.indices.get(), chunk.num_indices * sizeof(u16)))
+      return false;
+    if (!file_data->WriteBytes(&chunk.vertex_declaration, sizeof(PortableVertexDeclaration)))
+      return false;
+    if (!file_data->WriteBytes(&chunk.primitive_type, sizeof(PrimitiveType)))
+      return false;
+    if (!file_data->WriteBytes(&chunk.components_available, sizeof(u32)))
+      return false;
+    if (!file_data->WriteBytes(&chunk.minimum_position, sizeof(Common::Vec3)))
+      return false;
+    if (!file_data->WriteBytes(&chunk.maximum_position, sizeof(Common::Vec3)))
+      return false;
+    if (!file_data->WriteBytes(&chunk.transform.data[0],
+                               chunk.transform.data.size() * sizeof(float)))
+    {
+      return false;
+    }
+
+    const std::size_t material_name_size = chunk.material_name.size();
+    if (!file_data->WriteBytes(&material_name_size, sizeof(std::size_t)))
+      return false;
+    if (!file_data->WriteBytes(&chunk.material_name[0], chunk.material_name.size() * sizeof(char)))
+      return false;
+  }
+  return true;
+}
+
+bool MeshData::FromGLTF(std::string_view gltf_file, MeshData* data)
+{
+  if (gltf_file.ends_with(".glb"))
+  {
+    ERROR_LOG_FMT(VIDEO, "File '{}' with glb extension is not supported at this time", gltf_file);
+    return false;
+  }
+
+  if (gltf_file.ends_with(".gltf"))
+  {
+    tinygltf::Model model;
+    tinygltf::TinyGLTF loader;
+    std::string model_errors;
+    std::string model_warnings;
+    if (!loader.LoadASCIIFromFile(&model, &model_errors, &model_warnings, std::string{gltf_file}))
+    {
+      ERROR_LOG_FMT(VIDEO, "File '{}' was invalid GLTF, error: {}, warning: {}", gltf_file,
+                    model_errors, model_warnings);
+      return false;
+    }
+    return ReadGLTF(gltf_file, model, data);
+  }
+
+  ERROR_LOG_FMT(VIDEO, "GLTF '{}' has invalid extension", gltf_file);
+  return false;
+}
+}  // namespace VideoCommon

Source/Core/VideoCommon/Assets/MeshAsset.h

@@ -0,0 +1,60 @@
+// Copyright 2023 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <map>
+#include <memory>
+#include <span>
+#include <string>
+#include <string_view>
+
+#include <picojson.h>
+
+#include "Common/CommonTypes.h"
+#include "Common/Matrix.h"
+
+#include "VideoCommon/Assets/CustomAsset.h"
+#include "VideoCommon/NativeVertexFormat.h"
+#include "VideoCommon/RenderState.h"
+
+namespace File
+{
+class IOFile;
+}
+
+namespace VideoCommon
+{
+struct MeshDataChunk
+{
+  std::unique_ptr<u8[]> vertex_data;
+  u32 vertex_stride;
+  u32 num_vertices;
+  std::unique_ptr<u16[]> indices;
+  u32 num_indices;
+  PortableVertexDeclaration vertex_declaration;
+  PrimitiveType primitive_type;
+  u32 components_available;
+  Common::Vec3 minimum_position;
+  Common::Vec3 maximum_position;
+  Common::Matrix44 transform;
+  std::string material_name;
+};
+
+struct MeshData
+{
+  static bool FromJson(const CustomAssetLibrary::AssetID& asset_id, const picojson::object& json,
+                       MeshData* data);
+  static void ToJson(picojson::object& obj, const MeshData& data);
+
+  static bool FromDolphinMesh(std::span<const u8> raw_data, MeshData* data);
+
+  static bool ToDolphinMesh(File::IOFile* file_data, const MeshData& data);
+
+  static bool FromGLTF(std::string_view gltf_file, MeshData* data);
+
+  std::vector<MeshDataChunk> m_mesh_chunks;
+  std::map<std::string, CustomAssetLibrary::AssetID, std::less<>>
+      m_mesh_material_to_material_asset_id;
+};
+}  // namespace VideoCommon

Source/Core/VideoCommon/CMakeLists.txt

@@ -20,6 +20,8 @@ add_library(videocommon
   Assets/DirectFilesystemAssetLibrary.h
   Assets/MaterialAsset.cpp
   Assets/MaterialAsset.h
+  Assets/MeshAsset.cpp
+  Assets/MeshAsset.h
   Assets/ShaderAsset.cpp
   Assets/ShaderAsset.h
   Assets/TextureAsset.cpp
@@ -216,6 +218,7 @@ PRIVATE
   imgui
   implot
   glslang
+  tinygltf
 )
 
 if(_M_X86_64)