dali-scene-loader/public-api/gltf2-loader.cpp

   1 /*
   2  * Copyright (c) 2022 Samsung Electronics Co., Ltd.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  *
  16  */
  17 #include "dali-scene-loader/public-api/gltf2-loader.h"
  18 #include <fstream>
  19 #include "dali-scene-loader/internal/gltf2-asset.h"
  20 #include "dali-scene-loader/public-api/load-result.h"
  21 #include "dali-scene-loader/public-api/resource-bundle.h"
  22 #include "dali-scene-loader/public-api/scene-definition.h"
  23 #include "dali-scene-loader/public-api/shader-definition-factory.h"
  24 #include "dali-scene-loader/public-api/utils.h"
  25 #include "dali/public-api/math/quaternion.h"
  26
  27 #define ENUM_STRING_MAPPING(t, x) \
  28   {                               \
  29 #x, t::x                      \
  30   }
  31
  32 namespace gt = gltf2;
  33 namespace js = json;
  34
  35 namespace Dali
  36 {
  37 namespace SceneLoader
  38 {
  39 namespace
  40 {
  41 const std::string POSITION_PROPERTY("position");
  42 const std::string ORIENTATION_PROPERTY("orientation");
  43 const std::string SCALE_PROPERTY("scale");
  44 const std::string BLEND_SHAPE_WEIGHTS_UNIFORM("uBlendShapeWeight");
  45 const std::string MRENDERER_MODEL_IDENTIFICATION("M-Renderer");
  46 const std::string ROOT_NODE_NAME("RootNode");
  47 const Vector3     SCALE_TO_ADJUST(100.0f, 100.0f, 100.0f);
  48
  49 constexpr float DEFAULT_INTENSITY = 0.5f;
  50
  51 const Geometry::Type GLTF2_TO_DALI_PRIMITIVES[]{
  52   Geometry::POINTS,
  53   Geometry::LINES,
  54   Geometry::LINE_LOOP,
  55   Geometry::LINE_STRIP,
  56   Geometry::TRIANGLES,
  57   Geometry::TRIANGLE_STRIP,
  58   Geometry::TRIANGLE_FAN}; //...because Dali swaps the last two.
  59
  60 struct AttributeMapping
  61 {
  62   gt::Attribute::Type      mType;
  63   MeshDefinition::Accessor MeshDefinition::*mAccessor;
  64   uint16_t                                  mElementSizeRequired;
  65 } ATTRIBUTE_MAPPINGS[]{
  66   {gt::Attribute::NORMAL, &MeshDefinition::mNormals, sizeof(Vector3)},
  67   {gt::Attribute::TANGENT, &MeshDefinition::mTangents, sizeof(Vector3)},
  68   {gt::Attribute::TEXCOORD_0, &MeshDefinition::mTexCoords, sizeof(Vector2)},
  69   {gt::Attribute::COLOR_0, &MeshDefinition::mColors, sizeof(Vector4)},
  70   {gt::Attribute::JOINTS_0, &MeshDefinition::mJoints0, sizeof(Vector4)},
  71   {gt::Attribute::WEIGHTS_0, &MeshDefinition::mWeights0, sizeof(Vector4)},
  72 };
  73
  74 std::vector<gt::Animation> ReadAnimationArray(const json_value_s& j)
  75 {
  76   gt::Animation proxy;
  77   SetRefReaderObject(proxy);
  78
  79   auto results = js::Read::Array<gt::Animation, js::ObjectReader<gt::Animation>::Read>(j);
  80
  81   for(auto& animation : results)
  82   {
  83     for(auto& channel : animation.mChannels)
  84     {
  85       channel.mSampler.UpdateVector(animation.mSamplers);
  86     }
  87   }
  88
  89   return results;
  90 }
  91
  92 void ApplyAccessorMinMax(const gt::Accessor& acc, float* values)
  93 {
  94   DALI_ASSERT_ALWAYS(acc.mMax.empty() || gt::AccessorType::ElementCount(acc.mType) == acc.mMax.size());
  95   DALI_ASSERT_ALWAYS(acc.mMin.empty() || gt::AccessorType::ElementCount(acc.mType) == acc.mMin.size());
  96   MeshDefinition::Blob::ApplyMinMax(acc.mMin, acc.mMax, acc.mCount, values);
  97 }
  98
  99 const auto BUFFER_READER = std::move(js::Reader<gt::Buffer>()
 100                                        .Register(*js::MakeProperty("byteLength", js::Read::Number<uint32_t>, &gt::Buffer::mByteLength))
 101                                        .Register(*js::MakeProperty("uri", js::Read::StringView, &gt::Buffer::mUri)));
 102
 103 const auto BUFFER_VIEW_READER = std::move(js::Reader<gt::BufferView>()
 104                                             .Register(*js::MakeProperty("buffer", gt::RefReader<gt::Document>::Read<gt::Buffer, &gt::Document::mBuffers>, &gt::BufferView::mBuffer))
 105                                             .Register(*js::MakeProperty("byteOffset", js::Read::Number<uint32_t>, &gt::BufferView::mByteOffset))
 106                                             .Register(*js::MakeProperty("byteLength", js::Read::Number<uint32_t>, &gt::BufferView::mByteLength))
 107                                             .Register(*js::MakeProperty("byteStride", js::Read::Number<uint32_t>, &gt::BufferView::mByteStride))
 108                                             .Register(*js::MakeProperty("target", js::Read::Number<uint32_t>, &gt::BufferView::mTarget)));
 109
 110 const auto BUFFER_VIEW_CLIENT_READER = std::move(js::Reader<gt::BufferViewClient>()
 111                                                    .Register(*js::MakeProperty("bufferView", gt::RefReader<gt::Document>::Read<gt::BufferView, &gt::Document::mBufferViews>, &gt::BufferViewClient::mBufferView))
 112                                                    .Register(*js::MakeProperty("byteOffset", js::Read::Number<uint32_t>, &gt::BufferViewClient::mByteOffset)));
 113
 114 const auto COMPONENT_TYPED_BUFFER_VIEW_CLIENT_READER = std::move(js::Reader<gt::ComponentTypedBufferViewClient>()
 115                                                                    .Register(*new js::Property<gt::ComponentTypedBufferViewClient, gt::Ref<gt::BufferView>>("bufferView", gt::RefReader<gt::Document>::Read<gt::BufferView, &gt::Document::mBufferViews>, &gt::ComponentTypedBufferViewClient::mBufferView))
 116                                                                    .Register(*new js::Property<gt::ComponentTypedBufferViewClient, uint32_t>("byteOffset", js::Read::Number<uint32_t>, &gt::ComponentTypedBufferViewClient::mByteOffset))
 117                                                                    .Register(*js::MakeProperty("componentType", js::Read::Enum<gt::Component::Type>, &gt::ComponentTypedBufferViewClient::mComponentType)));
 118
 119 const auto ACCESSOR_SPARSE_READER = std::move(js::Reader<gt::Accessor::Sparse>()
 120                                                 .Register(*js::MakeProperty("count", js::Read::Number<uint32_t>, &gt::Accessor::Sparse::mCount))
 121                                                 .Register(*js::MakeProperty("indices", js::ObjectReader<gt::ComponentTypedBufferViewClient>::Read, &gt::Accessor::Sparse::mIndices))
 122                                                 .Register(*js::MakeProperty("values", js::ObjectReader<gt::BufferViewClient>::Read, &gt::Accessor::Sparse::mValues)));
 123
 124 const auto ACCESSOR_READER = std::move(js::Reader<gt::Accessor>()
 125                                          .Register(*new js::Property<gt::Accessor, gt::Ref<gt::BufferView>>("bufferView",
 126                                                                                                             gt::RefReader<gt::Document>::Read<gt::BufferView, &gt::Document::mBufferViews>,
 127                                                                                                             &gt::Accessor::mBufferView))
 128                                          .Register(*new js::Property<gt::Accessor, uint32_t>("byteOffset",
 129                                                                                              js::Read::Number<uint32_t>,
 130                                                                                              &gt::Accessor::mByteOffset))
 131                                          .Register(*new js::Property<gt::Accessor, gt::Component::Type>("componentType",
 132                                                                                                         js::Read::Enum<gt::Component::Type>,
 133                                                                                                         &gt::Accessor::mComponentType))
 134                                          .Register(*new js::Property<gt::Accessor, std::string_view>("name", js::Read::StringView, &gt::Accessor::mName))
 135                                          .Register(*js::MakeProperty("count", js::Read::Number<uint32_t>, &gt::Accessor::mCount))
 136                                          .Register(*js::MakeProperty("normalized", js::Read::Boolean, &gt::Accessor::mNormalized))
 137                                          .Register(*js::MakeProperty("type", gt::ReadStringEnum<gt::AccessorType>, &gt::Accessor::mType))
 138                                          .Register(*js::MakeProperty("min", js::Read::Array<float, js::Read::Number>, &gt::Accessor::mMin))
 139                                          .Register(*js::MakeProperty("max", js::Read::Array<float, js::Read::Number>, &gt::Accessor::mMax))
 140                                          .Register(*new js::Property<gt::Accessor, gt::Accessor::Sparse>("sparse", js::ObjectReader<gt::Accessor::Sparse>::Read, &gt::Accessor::SetSparse)));
 141
 142 const auto IMAGE_READER = std::move(js::Reader<gt::Image>()
 143                                       .Register(*new js::Property<gt::Image, std::string_view>("name", js::Read::StringView, &gt::Material::mName))
 144                                       .Register(*js::MakeProperty("uri", js::Read::StringView, &gt::Image::mUri))
 145                                       .Register(*js::MakeProperty("mimeType", js::Read::StringView, &gt::Image::mMimeType))
 146                                       .Register(*js::MakeProperty("bufferView", gt::RefReader<gt::Document>::Read<gt::BufferView, &gt::Document::mBufferViews>, &gt::Image::mBufferView)));
 147
 148 const auto SAMPLER_READER = std::move(js::Reader<gt::Sampler>()
 149                                         .Register(*js::MakeProperty("minFilter", js::Read::Enum<gt::Filter::Type>, &gt::Sampler::mMinFilter))
 150                                         .Register(*js::MakeProperty("magFilter", js::Read::Enum<gt::Filter::Type>, &gt::Sampler::mMagFilter))
 151                                         .Register(*js::MakeProperty("wrapS", js::Read::Enum<gt::Wrap::Type>, &gt::Sampler::mWrapS))
 152                                         .Register(*js::MakeProperty("wrapT", js::Read::Enum<gt::Wrap::Type>, &gt::Sampler::mWrapT)));
 153
 154 const auto TEXURE_READER = std::move(js::Reader<gt::Texture>()
 155                                        .Register(*js::MakeProperty("source", gt::RefReader<gt::Document>::Read<gt::Image, &gt::Document::mImages>, &gt::Texture::mSource))
 156                                        .Register(*js::MakeProperty("sampler", gt::RefReader<gt::Document>::Read<gt::Sampler, &gt::Document::mSamplers>, &gt::Texture::mSampler)));
 157
 158 const auto TEXURE_INFO_READER = std::move(js::Reader<gt::TextureInfo>()
 159                                             .Register(*js::MakeProperty("index", gt::RefReader<gt::Document>::Read<gt::Texture, &gt::Document::mTextures>, &gt::TextureInfo::mTexture))
 160                                             .Register(*js::MakeProperty("texCoord", js::Read::Number<uint32_t>, &gt::TextureInfo::mTexCoord))
 161                                             .Register(*js::MakeProperty("scale", js::Read::Number<float>, &gt::TextureInfo::mScale))
 162                                             .Register(*js::MakeProperty("strength", js::Read::Number<float>, &gt::TextureInfo::mStrength)));
 163
 164 const auto MATERIAL_PBR_READER = std::move(js::Reader<gt::Material::Pbr>()
 165                                              .Register(*js::MakeProperty("baseColorFactor", gt::ReadDaliVector<Vector4>, &gt::Material::Pbr::mBaseColorFactor))
 166                                              .Register(*js::MakeProperty("baseColorTexture", js::ObjectReader<gt::TextureInfo>::Read, &gt::Material::Pbr::mBaseColorTexture))
 167                                              .Register(*js::MakeProperty("metallicFactor", js::Read::Number<float>, &gt::Material::Pbr::mMetallicFactor))
 168                                              .Register(*js::MakeProperty("roughnessFactor", js::Read::Number<float>, &gt::Material::Pbr::mRoughnessFactor))
 169                                              .Register(*js::MakeProperty("metallicRoughnessTexture", js::ObjectReader<gt::TextureInfo>::Read, &gt::Material::Pbr::mMetallicRoughnessTexture)));
 170
 171 const auto MATERIAL_READER = std::move(js::Reader<gt::Material>()
 172                                          .Register(*new js::Property<gt::Material, std::string_view>("name", js::Read::StringView, &gt::Material::mName))
 173                                          .Register(*js::MakeProperty("pbrMetallicRoughness", js::ObjectReader<gt::Material::Pbr>::Read, &gt::Material::mPbrMetallicRoughness))
 174                                          .Register(*js::MakeProperty("normalTexture", js::ObjectReader<gt::TextureInfo>::Read, &gt::Material::mNormalTexture))
 175                                          .Register(*js::MakeProperty("occlusionTexture", js::ObjectReader<gt::TextureInfo>::Read, &gt::Material::mOcclusionTexture))
 176                                          .Register(*js::MakeProperty("emissiveTexture", js::ObjectReader<gt::TextureInfo>::Read, &gt::Material::mEmissiveTexture))
 177                                          .Register(*js::MakeProperty("emissiveFactor", gt::ReadDaliVector<Vector3>, &gt::Material::mEmissiveFactor))
 178                                          .Register(*js::MakeProperty("alphaMode", gt::ReadStringEnum<gt::AlphaMode>, &gt::Material::mAlphaMode))
 179                                          .Register(*js::MakeProperty("alphaCutoff", js::Read::Number<float>, &gt::Material::mAlphaCutoff)));
 180
 181 std::map<gt::Attribute::Type, gt::Ref<gt::Accessor>> ReadMeshPrimitiveAttributes(const json_value_s& j)
 182 {
 183   auto&                                                jo = js::Cast<json_object_s>(j);
 184   std::map<gt::Attribute::Type, gt::Ref<gt::Accessor>> result;
 185
 186   auto i = jo.start;
 187   while(i)
 188   {
 189     auto jstr                                                        = *i->name;
 190     result[gt::Attribute::FromString(jstr.string, jstr.string_size)] = gt::RefReader<gt::Document>::Read<gt::Accessor, &gt::Document::mAccessors>(*i->value);
 191     i                                                                = i->next;
 192   }
 193   return result;
 194 }
 195
 196 std::vector<std::map<gt::Attribute::Type, gt::Ref<gt::Accessor>>> ReadMeshPrimitiveTargets(const json_value_s& j)
 197 {
 198   auto&                                                             jo = js::Cast<json_array_s>(j);
 199   std::vector<std::map<gt::Attribute::Type, gt::Ref<gt::Accessor>>> result;
 200
 201   result.reserve(jo.length);
 202
 203   auto i = jo.start;
 204   while(i)
 205   {
 206     result.push_back(std::move(ReadMeshPrimitiveAttributes(*i->value)));
 207     i = i->next;
 208   }
 209
 210   return result;
 211 }
 212
 213 const auto MESH_PRIMITIVE_READER = std::move(js::Reader<gt::Mesh::Primitive>()
 214                                                .Register(*js::MakeProperty("attributes", ReadMeshPrimitiveAttributes, &gt::Mesh::Primitive::mAttributes))
 215                                                .Register(*js::MakeProperty("indices", gt::RefReader<gt::Document>::Read<gt::Accessor, &gt::Document::mAccessors>, &gt::Mesh::Primitive::mIndices))
 216                                                .Register(*js::MakeProperty("material", gt::RefReader<gt::Document>::Read<gt::Material, &gt::Document::mMaterials>, &gt::Mesh::Primitive::mMaterial))
 217                                                .Register(*js::MakeProperty("mode", js::Read::Enum<gt::Mesh::Primitive::Mode>, &gt::Mesh::Primitive::mMode))
 218                                                .Register(*js::MakeProperty("targets", ReadMeshPrimitiveTargets, &gt::Mesh::Primitive::mTargets)));
 219
 220 const auto MESH_READER = std::move(js::Reader<gt::Mesh>()
 221                                      .Register(*new js::Property<gt::Mesh, std::string_view>("name", js::Read::StringView, &gt::Mesh::mName))
 222                                      .Register(*js::MakeProperty("primitives",
 223                                                                  js::Read::Array<gt::Mesh::Primitive, js::ObjectReader<gt::Mesh::Primitive>::Read>,
 224                                                                  &gt::Mesh::mPrimitives))
 225                                      .Register(*js::MakeProperty("weights", js::Read::Array<float, js::Read::Number>, &gt::Mesh::mWeights)));
 226
 227 const auto SKIN_READER = std::move(js::Reader<gt::Skin>()
 228                                      .Register(*new js::Property<gt::Skin, std::string_view>("name", js::Read::StringView, &gt::Skin::mName))
 229                                      .Register(*js::MakeProperty("inverseBindMatrices",
 230                                                                  gt::RefReader<gt::Document>::Read<gt::Accessor, &gt::Document::mAccessors>,
 231                                                                  &gt::Skin::mInverseBindMatrices))
 232                                      .Register(*js::MakeProperty("skeleton",
 233                                                                  gt::RefReader<gt::Document>::Read<gt::Node, &gt::Document::mNodes>,
 234                                                                  &gt::Skin::mSkeleton))
 235                                      .Register(*js::MakeProperty("joints",
 236                                                                  js::Read::Array<gt::Ref<gt::Node>, gt::RefReader<gt::Document>::Read<gt::Node, &gt::Document::mNodes>>,
 237                                                                  &gt::Skin::mJoints)));
 238
 239 const auto CAMERA_PERSPECTIVE_READER = std::move(js::Reader<gt::Camera::Perspective>()
 240                                                    .Register(*js::MakeProperty("aspectRatio", js::Read::Number<float>, &gt::Camera::Perspective::mAspectRatio))
 241                                                    .Register(*js::MakeProperty("yfov", js::Read::Number<float>, &gt::Camera::Perspective::mYFov))
 242                                                    .Register(*js::MakeProperty("zfar", js::Read::Number<float>, &gt::Camera::Perspective::mZFar))
 243                                                    .Register(*js::MakeProperty("znear", js::Read::Number<float>, &gt::Camera::Perspective::mZNear))); // TODO: infinite perspective projection, where znear is omitted
 244
 245 const auto CAMERA_ORTHOGRAPHIC_READER = std::move(js::Reader<gt::Camera::Orthographic>()
 246                                                     .Register(*js::MakeProperty("xmag", js::Read::Number<float>, &gt::Camera::Orthographic::mXMag))
 247                                                     .Register(*js::MakeProperty("ymag", js::Read::Number<float>, &gt::Camera::Orthographic::mXMag))
 248                                                     .Register(*js::MakeProperty("zfar", js::Read::Number<float>, &gt::Camera::Orthographic::mZFar))
 249                                                     .Register(*js::MakeProperty("znear", js::Read::Number<float>, &gt::Camera::Orthographic::mZNear)));
 250
 251 const auto CAMERA_READER = std::move(js::Reader<gt::Camera>()
 252                                        .Register(*new js::Property<gt::Camera, std::string_view>("name", js::Read::StringView, &gt::Camera::mName))
 253                                        .Register(*js::MakeProperty("type", js::Read::StringView, &gt::Camera::mType))
 254                                        .Register(*js::MakeProperty("perspective", js::ObjectReader<gt::Camera::Perspective>::Read, &gt::Camera::mPerspective))
 255                                        .Register(*js::MakeProperty("orthographic", js::ObjectReader<gt::Camera::Orthographic>::Read, &gt::Camera::mOrthographic)));
 256
 257 const auto NODE_READER = std::move(js::Reader<gt::Node>()
 258                                      .Register(*new js::Property<gt::Node, std::string_view>("name", js::Read::StringView, &gt::Node::mName))
 259                                      .Register(*js::MakeProperty("translation", gt::ReadDaliVector<Vector3>, &gt::Node::mTranslation))
 260                                      .Register(*js::MakeProperty("rotation", gt::ReadQuaternion, &gt::Node::mRotation))
 261                                      .Register(*js::MakeProperty("scale", gt::ReadDaliVector<Vector3>, &gt::Node::mScale))
 262                                      .Register(*new js::Property<gt::Node, Matrix>("matrix", gt::ReadDaliVector<Matrix>, &gt::Node::SetMatrix))
 263                                      .Register(*js::MakeProperty("camera", gt::RefReader<gt::Document>::Read<gt::Camera, &gt::Document::mCameras>, &gt::Node::mCamera))
 264                                      .Register(*js::MakeProperty("children", js::Read::Array<gt::Ref<gt::Node>, gt::RefReader<gt::Document>::Read<gt::Node, &gt::Document::mNodes>>, &gt::Node::mChildren))
 265                                      .Register(*js::MakeProperty("mesh", gt::RefReader<gt::Document>::Read<gt::Mesh, &gt::Document::mMeshes>, &gt::Node::mMesh))
 266                                      .Register(*js::MakeProperty("skin", gt::RefReader<gt::Document>::Read<gt::Skin, &gt::Document::mSkins>, &gt::Node::mSkin)));
 267
 268 const auto ANIMATION_SAMPLER_READER = std::move(js::Reader<gt::Animation::Sampler>()
 269                                                   .Register(*js::MakeProperty("input", gt::RefReader<gt::Document>::Read<gt::Accessor, &gt::Document::mAccessors>, &gt::Animation::Sampler::mInput))
 270                                                   .Register(*js::MakeProperty("output", gt::RefReader<gt::Document>::Read<gt::Accessor, &gt::Document::mAccessors>, &gt::Animation::Sampler::mOutput))
 271                                                   .Register(*js::MakeProperty("interpolation", gt::ReadStringEnum<gt::Animation::Sampler::Interpolation>, &gt::Animation::Sampler::mInterpolation)));
 272
 273 const auto ANIMATION_TARGET_READER = std::move(js::Reader<gt::Animation::Channel::Target>()
 274                                                  .Register(*js::MakeProperty("node", gt::RefReader<gt::Document>::Read<gt::Node, &gt::Document::mNodes>, &gt::Animation::Channel::Target::mNode))
 275                                                  .Register(*js::MakeProperty("path", gt::ReadStringEnum<gt::Animation::Channel::Target>, &gt::Animation::Channel::Target::mPath)));
 276
 277 const auto ANIMATION_CHANNEL_READER = std::move(js::Reader<gt::Animation::Channel>()
 278                                                   .Register(*js::MakeProperty("target", js::ObjectReader<gt::Animation::Channel::Target>::Read, &gt::Animation::Channel::mTarget))
 279                                                   .Register(*js::MakeProperty("sampler", gt::RefReader<gt::Animation>::Read<gt::Animation::Sampler, &gt::Animation::mSamplers>, &gt::Animation::Channel::mSampler)));
 280
 281 const auto ANIMATION_READER = std::move(js::Reader<gt::Animation>()
 282                                           .Register(*new js::Property<gt::Animation, std::string_view>("name", js::Read::StringView, &gt::Animation::mName))
 283                                           .Register(*js::MakeProperty("samplers",
 284                                                                       js::Read::Array<gt::Animation::Sampler, js::ObjectReader<gt::Animation::Sampler>::Read>,
 285                                                                       &gt::Animation::mSamplers))
 286                                           .Register(*js::MakeProperty("channels",
 287                                                                       js::Read::Array<gt::Animation::Channel, js::ObjectReader<gt::Animation::Channel>::Read>,
 288                                                                       &gt::Animation::mChannels)));
 289
 290 const auto SCENE_READER = std::move(js::Reader<gt::Scene>()
 291                                       .Register(*new js::Property<gt::Scene, std::string_view>("name", js::Read::StringView, &gt::Scene::mName))
 292                                       .Register(*js::MakeProperty("nodes",
 293                                                                   js::Read::Array<gt::Ref<gt::Node>, gt::RefReader<gt::Document>::Read<gt::Node, &gt::Document::mNodes>>,
 294                                                                   &gt::Scene::mNodes)));
 295
 296 const auto DOCUMENT_READER = std::move(js::Reader<gt::Document>()
 297                                          .Register(*js::MakeProperty("buffers",
 298                                                                      js::Read::Array<gt::Buffer, js::ObjectReader<gt::Buffer>::Read>,
 299                                                                      &gt::Document::mBuffers))
 300                                          .Register(*js::MakeProperty("bufferViews",
 301                                                                      js::Read::Array<gt::BufferView, js::ObjectReader<gt::BufferView>::Read>,
 302                                                                      &gt::Document::mBufferViews))
 303                                          .Register(*js::MakeProperty("accessors",
 304                                                                      js::Read::Array<gt::Accessor, js::ObjectReader<gt::Accessor>::Read>,
 305                                                                      &gt::Document::mAccessors))
 306                                          .Register(*js::MakeProperty("images",
 307                                                                      js::Read::Array<gt::Image, js::ObjectReader<gt::Image>::Read>,
 308                                                                      &gt::Document::mImages))
 309                                          .Register(*js::MakeProperty("samplers",
 310                                                                      js::Read::Array<gt::Sampler, js::ObjectReader<gt::Sampler>::Read>,
 311                                                                      &gt::Document::mSamplers))
 312                                          .Register(*js::MakeProperty("textures",
 313                                                                      js::Read::Array<gt::Texture, js::ObjectReader<gt::Texture>::Read>,
 314                                                                      &gt::Document::mTextures))
 315                                          .Register(*js::MakeProperty("materials",
 316                                                                      js::Read::Array<gt::Material, js::ObjectReader<gt::Material>::Read>,
 317                                                                      &gt::Document::mMaterials))
 318                                          .Register(*js::MakeProperty("meshes",
 319                                                                      js::Read::Array<gt::Mesh, js::ObjectReader<gt::Mesh>::Read>,
 320                                                                      &gt::Document::mMeshes))
 321                                          .Register(*js::MakeProperty("skins",
 322                                                                      js::Read::Array<gt::Skin, js::ObjectReader<gt::Skin>::Read>,
 323                                                                      &gt::Document::mSkins))
 324                                          .Register(*js::MakeProperty("cameras",
 325                                                                      js::Read::Array<gt::Camera, js::ObjectReader<gt::Camera>::Read>,
 326                                                                      &gt::Document::mCameras))
 327                                          .Register(*js::MakeProperty("nodes",
 328                                                                      js::Read::Array<gt::Node, js::ObjectReader<gt::Node>::Read>,
 329                                                                      &gt::Document::mNodes))
 330                                          .Register(*js::MakeProperty("animations",
 331                                                                      ReadAnimationArray,
 332                                                                      &gt::Document::mAnimations))
 333                                          .Register(*js::MakeProperty("scenes",
 334                                                                      js::Read::Array<gt::Scene, js::ObjectReader<gt::Scene>::Read>,
 335                                                                      &gt::Document::mScenes))
 336                                          .Register(*js::MakeProperty("scene", gt::RefReader<gt::Document>::Read<gt::Scene, &gt::Document::mScenes>, &gt::Document::mScene)));
 337
 338 struct NodeMapping
 339 {
 340   Index gltfIdx;
 341   Index runtimeIdx;
 342 };
 343
 344 bool operator<(const NodeMapping& mapping, Index gltfIdx)
 345 {
 346   return mapping.gltfIdx < gltfIdx;
 347 }
 348
 349 class NodeIndexMapper
 350 {
 351 public:
 352   NodeIndexMapper()                       = default;
 353   NodeIndexMapper(const NodeIndexMapper&) = delete;
 354   NodeIndexMapper& operator=(const NodeIndexMapper&) = delete;
 355
 356   ///@brief Registers a mapping of the @a gltfIdx of a node to its @a runtimeIdx .
 357   ///@note If the indices are the same, the registration is omitted, in order to
 358   /// save growing a vector.
 359   void RegisterMapping(Index gltfIdx, Index runtimeIdx)
 360   {
 361     if(gltfIdx != runtimeIdx)
 362     {
 363       auto iInsert = std::lower_bound(mNodes.begin(), mNodes.end(), gltfIdx);
 364       DALI_ASSERT_DEBUG(iInsert == mNodes.end() || iInsert->gltfIdx != gltfIdx);
 365       mNodes.insert(iInsert, NodeMapping{gltfIdx, runtimeIdx});
 366     }
 367   }
 368
 369   ///@brief Retrieves the runtime index of a Node, mapped to the given @a gltfIdx.
 370   Index GetRuntimeId(Index gltfIdx) const
 371   {
 372     auto iFind = std::lower_bound(mNodes.begin(), mNodes.end(), gltfIdx); // using custom operator<
 373     return (iFind != mNodes.end() && iFind->gltfIdx == gltfIdx) ? iFind->runtimeIdx : gltfIdx;
 374   }
 375
 376 private:
 377   std::vector<NodeMapping> mNodes;
 378 };
 379
 380 struct ConversionContext
 381 {
 382   LoadResult& mOutput;
 383
 384   std::string mPath;
 385   Index       mDefaultMaterial;
 386
 387   std::vector<Index> mMeshIds;
 388   NodeIndexMapper    mNodeIndices;
 389 };
 390
 391 SamplerFlags::Type ConvertWrapMode(gt::Wrap::Type w)
 392 {
 393   switch(w)
 394   {
 395     case gt::Wrap::REPEAT:
 396       return SamplerFlags::WRAP_REPEAT;
 397     case gt::Wrap::CLAMP_TO_EDGE:
 398       return SamplerFlags::WRAP_CLAMP;
 399     case gt::Wrap::MIRRORED_REPEAT:
 400       return SamplerFlags::WRAP_MIRROR;
 401     default:
 402       throw std::runtime_error("Invalid wrap type.");
 403   }
 404 }
 405
 406 SamplerFlags::Type ConvertSampler(const gt::Ref<gt::Sampler>& s)
 407 {
 408   if(s)
 409   {
 410     return (s->mMinFilter < gt::Filter::NEAREST_MIPMAP_NEAREST) ? (s->mMinFilter - gt::Filter::NEAREST) : ((s->mMinFilter - gt::Filter::NEAREST_MIPMAP_NEAREST) + 2) | ((s->mMagFilter - gt::Filter::NEAREST) << SamplerFlags::FILTER_MAG_SHIFT) | (ConvertWrapMode(s->mWrapS) << SamplerFlags::WRAP_S_SHIFT) | (ConvertWrapMode(s->mWrapT) << SamplerFlags::WRAP_T_SHIFT);
 411   }
 412   else
 413   {
 414     // https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#texturesampler
 415     // "The index of the sampler used by this texture. When undefined, a sampler with repeat wrapping and auto filtering should be used."
 416     // "What is an auto filtering", I hear you ask. Since there's nothing else to determine mipmapping from - including glTF image
 417     // properties, if not in some extension -, we will simply assume linear filtering.
 418     return SamplerFlags::FILTER_LINEAR | (SamplerFlags::FILTER_LINEAR << SamplerFlags::FILTER_MAG_SHIFT) |
 419            (SamplerFlags::WRAP_REPEAT << SamplerFlags::WRAP_S_SHIFT) | (SamplerFlags::WRAP_REPEAT << SamplerFlags::WRAP_T_SHIFT);
 420   }
 421 }
 422
 423 TextureDefinition ConvertTextureInfo(const gt::TextureInfo& mm)
 424 {
 425   return TextureDefinition{std::string(mm.mTexture->mSource->mUri), ConvertSampler(mm.mTexture->mSampler)};
 426 }
 427
 428 void ConvertMaterial(const gt::Material& m, decltype(ResourceBundle::mMaterials)& outMaterials)
 429 {
 430   MaterialDefinition matDef;
 431
 432   auto& pbr = m.mPbrMetallicRoughness;
 433   if(m.mAlphaMode != gt::AlphaMode::OPAQUE || pbr.mBaseColorFactor.a < 1.f)
 434   {
 435     matDef.mFlags |= MaterialDefinition::TRANSPARENCY;
 436   }
 437
 438   if(m.mAlphaMode == gt::AlphaMode::MASK)
 439   {
 440     matDef.SetAlphaCutoff(std::min(1.f, std::max(0.f, m.mAlphaCutoff)));
 441   }
 442
 443   matDef.mBaseColorFactor = pbr.mBaseColorFactor;
 444
 445   matDef.mTextureStages.reserve(!!pbr.mBaseColorTexture + !!pbr.mMetallicRoughnessTexture + !!m.mNormalTexture + !!m.mOcclusionTexture + !!m.mEmissiveTexture);
 446   if(pbr.mBaseColorTexture)
 447   {
 448     const auto semantic = MaterialDefinition::ALBEDO;
 449     matDef.mTextureStages.push_back({semantic, ConvertTextureInfo(pbr.mBaseColorTexture)});
 450     // TODO: and there had better be one
 451     matDef.mFlags |= semantic;
 452   }
 453   else
 454   {
 455     matDef.mNeedAlbedoTexture = false;
 456   }
 457
 458   matDef.mMetallic  = pbr.mMetallicFactor;
 459   matDef.mRoughness = pbr.mRoughnessFactor;
 460
 461   if(pbr.mMetallicRoughnessTexture)
 462   {
 463     const auto semantic = MaterialDefinition::METALLIC | MaterialDefinition::ROUGHNESS |
 464                           MaterialDefinition::GLTF_CHANNELS;
 465     matDef.mTextureStages.push_back({semantic, ConvertTextureInfo(pbr.mMetallicRoughnessTexture)});
 466     // TODO: and there had better be one
 467     matDef.mFlags |= semantic;
 468   }
 469   else
 470   {
 471     matDef.mNeedMetallicRoughnessTexture = false;
 472   }
 473
 474   matDef.mNormalScale = m.mNormalTexture.mScale;
 475   if(m.mNormalTexture)
 476   {
 477     const auto semantic = MaterialDefinition::NORMAL;
 478     matDef.mTextureStages.push_back({semantic, ConvertTextureInfo(m.mNormalTexture)});
 479     // TODO: and there had better be one
 480     matDef.mFlags |= semantic;
 481   }
 482   else
 483   {
 484     matDef.mNeedNormalTexture = false;
 485   }
 486
 487   // TODO: handle doubleSided
 488   if(m.mOcclusionTexture)
 489   {
 490     const auto semantic = MaterialDefinition::OCCLUSION;
 491     matDef.mTextureStages.push_back({semantic, ConvertTextureInfo(m.mOcclusionTexture)});
 492     // TODO: and there had better be one
 493     matDef.mFlags |= semantic;
 494     matDef.mOcclusionStrength = m.mOcclusionTexture.mStrength;
 495   }
 496
 497   if(m.mEmissiveTexture)
 498   {
 499     const auto semantic = MaterialDefinition::EMISSIVE;
 500     matDef.mTextureStages.push_back({semantic, ConvertTextureInfo(m.mEmissiveTexture)});
 501     // TODO: and there had better be one
 502     matDef.mFlags |= semantic;
 503     matDef.mEmissiveFactor = m.mEmissiveFactor;
 504   }
 505
 506   outMaterials.emplace_back(std::move(matDef), TextureSet());
 507 }
 508
 509 void ConvertMaterials(const gt::Document& doc, ConversionContext& cctx)
 510 {
 511   auto& outMaterials = cctx.mOutput.mResources.mMaterials;
 512   outMaterials.reserve(doc.mMaterials.size());
 513
 514   for(auto& m : doc.mMaterials)
 515   {
 516     ConvertMaterial(m, outMaterials);
 517   }
 518 }
 519
 520 MeshDefinition::Accessor ConvertMeshPrimitiveAccessor(const gt::Accessor& acc)
 521 {
 522   DALI_ASSERT_ALWAYS((acc.mBufferView &&
 523                       (acc.mBufferView->mByteStride < std::numeric_limits<uint16_t>::max())) ||
 524                      (acc.mSparse && !acc.mBufferView));
 525
 526   DALI_ASSERT_ALWAYS(!acc.mSparse ||
 527                      ((acc.mSparse->mIndices.mBufferView && (acc.mSparse->mIndices.mBufferView->mByteStride < std::numeric_limits<uint16_t>::max())) &&
 528                       (acc.mSparse->mValues.mBufferView && (acc.mSparse->mValues.mBufferView->mByteStride < std::numeric_limits<uint16_t>::max()))));
 529
 530   MeshDefinition::SparseBlob sparseBlob;
 531   if(acc.mSparse)
 532   {
 533     const gt::Accessor::Sparse&               sparse  = *acc.mSparse;
 534     const gt::ComponentTypedBufferViewClient& indices = sparse.mIndices;
 535     const gt::BufferViewClient&               values  = sparse.mValues;
 536
 537     MeshDefinition::Blob indicesBlob(
 538       indices.mBufferView->mByteOffset + indices.mByteOffset,
 539       sparse.mCount * indices.GetBytesPerComponent(),
 540       static_cast<uint16_t>(indices.mBufferView->mByteStride),
 541       static_cast<uint16_t>(indices.GetBytesPerComponent()),
 542       {},
 543       {});
 544     MeshDefinition::Blob valuesBlob(
 545       values.mBufferView->mByteOffset + values.mByteOffset,
 546       sparse.mCount * acc.GetElementSizeBytes(),
 547       static_cast<uint16_t>(values.mBufferView->mByteStride),
 548       static_cast<uint16_t>(acc.GetElementSizeBytes()),
 549       {},
 550       {});
 551
 552     sparseBlob = std::move(MeshDefinition::SparseBlob(std::move(indicesBlob), std::move(valuesBlob), acc.mSparse->mCount));
 553   }
 554
 555   uint32_t bufferViewOffset = 0u;
 556   uint32_t bufferViewStride = 0u;
 557   if(acc.mBufferView)
 558   {
 559     bufferViewOffset = acc.mBufferView->mByteOffset;
 560     bufferViewStride = acc.mBufferView->mByteStride;
 561   }
 562
 563   return MeshDefinition::Accessor{
 564     std::move(MeshDefinition::Blob{bufferViewOffset + acc.mByteOffset,
 565                                    acc.GetBytesLength(),
 566                                    static_cast<uint16_t>(bufferViewStride),
 567                                    static_cast<uint16_t>(acc.GetElementSizeBytes()),
 568                                    acc.mMin,
 569                                    acc.mMax}),
 570     std::move(sparseBlob)};
 571 }
 572
 573 void ConvertMeshes(const gt::Document& doc, ConversionContext& cctx)
 574 {
 575   uint32_t meshCount = 0;
 576   cctx.mMeshIds.reserve(doc.mMeshes.size());
 577   for(auto& m : doc.mMeshes)
 578   {
 579     cctx.mMeshIds.push_back(meshCount);
 580     meshCount += m.mPrimitives.size();
 581   }
 582
 583   auto& outMeshes = cctx.mOutput.mResources.mMeshes;
 584   outMeshes.reserve(meshCount);
 585   for(auto& m : doc.mMeshes)
 586   {
 587     for(auto& p : m.mPrimitives)
 588     {
 589       MeshDefinition meshDef;
 590
 591       auto& attribs          = p.mAttributes;
 592       meshDef.mUri           = attribs.begin()->second->mBufferView->mBuffer->mUri;
 593       meshDef.mPrimitiveType = GLTF2_TO_DALI_PRIMITIVES[p.mMode];
 594
 595       auto& accPositions = *attribs.find(gt::Attribute::POSITION)->second;
 596       meshDef.mPositions = ConvertMeshPrimitiveAccessor(accPositions);
 597       // glTF2 support vector4 tangent for mesh.
 598       // https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#meshes-overview
 599       meshDef.mTangentType = Property::VECTOR4;
 600
 601       const bool needNormalsTangents = accPositions.mType == gt::AccessorType::VEC3;
 602       for(auto& am : ATTRIBUTE_MAPPINGS)
 603       {
 604         auto iFind = attribs.find(am.mType);
 605         if(iFind != attribs.end())
 606         {
 607           DALI_ASSERT_DEBUG(iFind->second->mBufferView->mBuffer->mUri.compare(meshDef.mUri) == 0);
 608           auto& accessor = meshDef.*(am.mAccessor);
 609           accessor       = ConvertMeshPrimitiveAccessor(*iFind->second);
 610
 611           if(iFind->first == gt::Attribute::JOINTS_0)
 612           {
 613             meshDef.mFlags |= (iFind->second->mComponentType == gt::Component::UNSIGNED_SHORT) * MeshDefinition::U16_JOINT_IDS;
 614             DALI_ASSERT_DEBUG(MaskMatch(meshDef.mFlags, MeshDefinition::U16_JOINT_IDS) || iFind->second->mComponentType == gt::Component::FLOAT);
 615           }
 616         }
 617         else if(needNormalsTangents)
 618         {
 619           switch(am.mType)
 620           {
 621             case gt::Attribute::NORMAL:
 622               meshDef.RequestNormals();
 623               break;
 624
 625             case gt::Attribute::TANGENT:
 626               meshDef.RequestTangents();
 627               break;
 628
 629             default:
 630               break;
 631           }
 632         }
 633       }
 634
 635       if(p.mIndices)
 636       {
 637         meshDef.mIndices = ConvertMeshPrimitiveAccessor(*p.mIndices);
 638         meshDef.mFlags |= (p.mIndices->mComponentType == gt::Component::UNSIGNED_INT) * MeshDefinition::U32_INDICES;
 639         DALI_ASSERT_DEBUG(MaskMatch(meshDef.mFlags, MeshDefinition::U32_INDICES) || p.mIndices->mComponentType == gt::Component::UNSIGNED_SHORT);
 640       }
 641
 642       if(!p.mTargets.empty())
 643       {
 644         meshDef.mBlendShapes.reserve(p.mTargets.size());
 645         meshDef.mBlendShapeVersion = BlendShapes::Version::VERSION_2_0;
 646         for(const auto& target : p.mTargets)
 647         {
 648           MeshDefinition::BlendShape blendShape;
 649
 650           auto endIt = target.end();
 651           auto it    = target.find(gt::Attribute::POSITION);
 652           if(it != endIt)
 653           {
 654             blendShape.deltas = ConvertMeshPrimitiveAccessor(*it->second);
 655           }
 656           it = target.find(gt::Attribute::NORMAL);
 657           if(it != endIt)
 658           {
 659             blendShape.normals = ConvertMeshPrimitiveAccessor(*it->second);
 660           }
 661           it = target.find(gt::Attribute::TANGENT);
 662           if(it != endIt)
 663           {
 664             blendShape.tangents = ConvertMeshPrimitiveAccessor(*it->second);
 665           }
 666
 667           if(!m.mWeights.empty())
 668           {
 669             blendShape.weight = m.mWeights[meshDef.mBlendShapes.size()];
 670           }
 671
 672           meshDef.mBlendShapes.push_back(std::move(blendShape));
 673         }
 674       }
 675
 676       outMeshes.push_back({std::move(meshDef), MeshGeometry{}});
 677     }
 678   }
 679 }
 680
 681 ModelNode* MakeModelNode(const gt::Mesh::Primitive& prim, ConversionContext& cctx)
 682 {
 683   auto modelNode = new ModelNode();
 684
 685   modelNode->mShaderIdx = 0; // TODO: further thought
 686
 687   auto materialIdx = prim.mMaterial.GetIndex();
 688   if(INVALID_INDEX == materialIdx)
 689   {
 690     // https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#default-material
 691     if(INVALID_INDEX == cctx.mDefaultMaterial)
 692     {
 693       auto& outMaterials    = cctx.mOutput.mResources.mMaterials;
 694       cctx.mDefaultMaterial = outMaterials.size();
 695
 696       ConvertMaterial(gt::Material{}, outMaterials);
 697     }
 698
 699     materialIdx = cctx.mDefaultMaterial;
 700   }
 701
 702   modelNode->mMaterialIdx = materialIdx;
 703
 704   return modelNode;
 705 }
 706
 707 void ConvertCamera(const gt::Camera& camera, CameraParameters& camParams)
 708 {
 709   camParams.isPerspective = camera.mType.compare("perspective") == 0;
 710   if(camParams.isPerspective)
 711   {
 712     auto& perspective = camera.mPerspective;
 713     camParams.yFov    = Degree(Radian(perspective.mYFov)).degree;
 714     camParams.zNear   = perspective.mZNear;
 715     camParams.zFar    = perspective.mZFar;
 716     // TODO: yes, we seem to ignore aspectRatio in CameraParameters.
 717   }
 718   else
 719   {
 720     auto& ortho                = camera.mOrthographic;
 721     camParams.orthographicSize = Vector4(-ortho.mXMag, ortho.mXMag, ortho.mYMag, -ortho.mYMag) * .5f;
 722     camParams.zNear            = ortho.mZNear;
 723     camParams.zFar             = ortho.mZFar;
 724   }
 725 }
 726
 727 void ConvertNode(gt::Node const& node, const Index gltfIdx, Index parentIdx, ConversionContext& cctx, bool isMRendererModel)
 728 {
 729   auto& output    = cctx.mOutput;
 730   auto& scene     = output.mScene;
 731   auto& resources = output.mResources;
 732
 733   const auto idx      = scene.GetNodeCount();
 734   auto       weakNode = scene.AddNode([&]() {
 735     std::unique_ptr<NodeDefinition> nodeDef{new NodeDefinition()};
 736
 737     nodeDef->mParentIdx = parentIdx;
 738     nodeDef->mName      = node.mName;
 739     if(nodeDef->mName.empty())
 740     {
 741       // TODO: Production quality generation of unique names.
 742       nodeDef->mName = std::to_string(reinterpret_cast<uintptr_t>(nodeDef.get()));
 743     }
 744
 745     if(!node.mSkin) // Nodes with skinned meshes are not supposed to have local transforms.
 746     {
 747       nodeDef->mPosition    = node.mTranslation;
 748       nodeDef->mOrientation = node.mRotation;
 749       nodeDef->mScale       = node.mScale;
 750
 751       if(isMRendererModel && node.mName == ROOT_NODE_NAME && node.mScale == SCALE_TO_ADJUST)
 752       {
 753         nodeDef->mScale *= 0.01f;
 754       }
 755     }
 756
 757     return nodeDef;
 758   }());
 759   if(!weakNode)
 760   {
 761     ExceptionFlinger(ASSERT_LOCATION) << "Node name '" << node.mName << "' is not unique; scene is invalid.";
 762   }
 763
 764   cctx.mNodeIndices.RegisterMapping(gltfIdx, idx);
 765
 766   Index skeletonIdx = node.mSkin ? node.mSkin.GetIndex() : INVALID_INDEX;
 767   if(node.mMesh && !node.mMesh->mPrimitives.empty())
 768   {
 769     auto& mesh = *node.mMesh;
 770
 771     auto iPrim          = mesh.mPrimitives.begin();
 772     auto modelNode      = MakeModelNode(*iPrim, cctx);
 773     auto meshIdx        = cctx.mMeshIds[node.mMesh.GetIndex()];
 774     modelNode->mMeshIdx = meshIdx;
 775
 776     weakNode->mRenderable.reset(modelNode);
 777
 778     DALI_ASSERT_DEBUG(resources.mMeshes[meshIdx].first.mSkeletonIdx == INVALID_INDEX ||
 779                       resources.mMeshes[meshIdx].first.mSkeletonIdx == skeletonIdx);
 780     resources.mMeshes[meshIdx].first.mSkeletonIdx = skeletonIdx;
 781
 782     // As does model-exporter, we'll create anonymous child nodes for additional mesh( primitiv)es.
 783     while(++iPrim != mesh.mPrimitives.end())
 784     {
 785       std::unique_ptr<NodeDefinition> child{new NodeDefinition};
 786       child->mParentIdx = idx;
 787
 788       auto childModel = MakeModelNode(*iPrim, cctx);
 789
 790       ++meshIdx;
 791       childModel->mMeshIdx = meshIdx;
 792
 793       child->mRenderable.reset(childModel);
 794
 795       scene.AddNode(std::move(child));
 796
 797       DALI_ASSERT_DEBUG(resources.mMeshes[meshIdx].first.mSkeletonIdx == INVALID_INDEX ||
 798                         resources.mMeshes[meshIdx].first.mSkeletonIdx == skeletonIdx);
 799       resources.mMeshes[meshIdx].first.mSkeletonIdx = skeletonIdx;
 800     }
 801   }
 802
 803   if(node.mCamera)
 804   {
 805     CameraParameters camParams;
 806     ConvertCamera(*node.mCamera, camParams);
 807
 808     camParams.matrix.SetTransformComponents(node.mScale, node.mRotation, node.mTranslation);
 809     output.mCameraParameters.push_back(camParams);
 810   }
 811
 812   for(auto& n : node.mChildren)
 813   {
 814     ConvertNode(*n, n.GetIndex(), idx, cctx, isMRendererModel);
 815   }
 816 }
 817
 818 void ConvertSceneNodes(const gt::Scene& scene, ConversionContext& cctx, bool isMRendererModel)
 819 {
 820   auto& outScene = cctx.mOutput.mScene;
 821   Index rootIdx  = outScene.GetNodeCount();
 822   switch(scene.mNodes.size())
 823   {
 824     case 0:
 825       break;
 826
 827     case 1:
 828       ConvertNode(*scene.mNodes[0], scene.mNodes[0].GetIndex(), INVALID_INDEX, cctx, isMRendererModel);
 829       outScene.AddRootNode(rootIdx);
 830       break;
 831
 832     default:
 833     {
 834       std::unique_ptr<NodeDefinition> sceneRoot{new NodeDefinition()};
 835       sceneRoot->mName = "GLTF_LOADER_SCENE_ROOT_" + std::to_string(outScene.GetRoots().size());
 836
 837       outScene.AddNode(std::move(sceneRoot));
 838       outScene.AddRootNode(rootIdx);
 839
 840       for(auto& n : scene.mNodes)
 841       {
 842         ConvertNode(*n, n.GetIndex(), rootIdx, cctx, isMRendererModel);
 843       }
 844       break;
 845     }
 846   }
 847 }
 848
 849 void ConvertNodes(const gt::Document& doc, ConversionContext& cctx, bool isMRendererModel)
 850 {
 851   ConvertSceneNodes(*doc.mScene, cctx, isMRendererModel);
 852
 853   for(uint32_t i = 0, i1 = doc.mScene.GetIndex(); i < i1; ++i)
 854   {
 855     ConvertSceneNodes(doc.mScenes[i], cctx, isMRendererModel);
 856   }
 857
 858   for(uint32_t i = doc.mScene.GetIndex() + 1; i < doc.mScenes.size(); ++i)
 859   {
 860     ConvertSceneNodes(doc.mScenes[i], cctx, isMRendererModel);
 861   }
 862 }
 863
 864 template<typename T>
 865 void LoadDataFromAccessor(const std::string& path, Vector<T>& dataBuffer, uint32_t offset, uint32_t size)
 866 {
 867   std::ifstream animationBinaryFile(path, std::ifstream::binary);
 868
 869   if(!animationBinaryFile.is_open())
 870   {
 871     throw std::runtime_error("Failed to load " + path);
 872   }
 873
 874   animationBinaryFile.seekg(offset);
 875   animationBinaryFile.read(reinterpret_cast<char*>(dataBuffer.Begin()), size);
 876   animationBinaryFile.close();
 877 }
 878
 879 template<typename T>
 880 float LoadDataFromAccessors(const std::string& path, const gltf2::Accessor& input, const gltf2::Accessor& output, Vector<float>& inputDataBuffer, Vector<T>& outputDataBuffer)
 881 {
 882   inputDataBuffer.Resize(input.mCount);
 883   outputDataBuffer.Resize(output.mCount);
 884
 885   const uint32_t inputDataBufferSize  = input.GetBytesLength();
 886   const uint32_t outputDataBufferSize = output.GetBytesLength();
 887
 888   LoadDataFromAccessor<float>(path + std::string(input.mBufferView->mBuffer->mUri), inputDataBuffer, input.mBufferView->mByteOffset + input.mByteOffset, inputDataBufferSize);
 889   LoadDataFromAccessor<T>(path + std::string(output.mBufferView->mBuffer->mUri), outputDataBuffer, output.mBufferView->mByteOffset + output.mByteOffset, outputDataBufferSize);
 890   ApplyAccessorMinMax(output, reinterpret_cast<float*>(outputDataBuffer.begin()));
 891
 892   return inputDataBuffer[input.mCount - 1u];
 893 }
 894
 895 template<typename T>
 896 float LoadKeyFrames(const std::string& path, const gt::Animation::Channel& channel, KeyFrames& keyFrames, gt::Animation::Channel::Target::Type type)
 897 {
 898   const gltf2::Accessor& input  = *channel.mSampler->mInput;
 899   const gltf2::Accessor& output = *channel.mSampler->mOutput;
 900
 901   Vector<float> inputDataBuffer;
 902   Vector<T>     outputDataBuffer;
 903
 904   const float duration = LoadDataFromAccessors<T>(path, input, output, inputDataBuffer, outputDataBuffer);
 905
 906   for(uint32_t i = 0; i < input.mCount; ++i)
 907   {
 908     keyFrames.Add(inputDataBuffer[i] / duration, outputDataBuffer[i]);
 909   }
 910
 911   return duration;
 912 }
 913
 914 float LoadBlendShapeKeyFrames(const std::string& path, const gt::Animation::Channel& channel, const std::string& nodeName, uint32_t& propertyIndex, std::vector<SceneLoader::AnimatedProperty>& properties)
 915 {
 916   const gltf2::Accessor& input  = *channel.mSampler->mInput;
 917   const gltf2::Accessor& output = *channel.mSampler->mOutput;
 918
 919   Vector<float> inputDataBuffer;
 920   Vector<float> outputDataBuffer;
 921
 922   const float duration = LoadDataFromAccessors<float>(path, input, output, inputDataBuffer, outputDataBuffer);
 923
 924   char        weightNameBuffer[32];
 925   auto        prefixSize    = snprintf(weightNameBuffer, sizeof(weightNameBuffer), "%s[", BLEND_SHAPE_WEIGHTS_UNIFORM.c_str());
 926   char* const pWeightName   = weightNameBuffer + prefixSize;
 927   const auto  remainingSize = sizeof(weightNameBuffer) - prefixSize;
 928   for(uint32_t weightIndex = 0u, endWeightIndex = channel.mSampler->mOutput->mCount / channel.mSampler->mInput->mCount; weightIndex < endWeightIndex; ++weightIndex)
 929   {
 930     AnimatedProperty& animatedProperty = properties[propertyIndex++];
 931
 932     animatedProperty.mNodeName = nodeName;
 933     snprintf(pWeightName, remainingSize, "%d]", weightIndex);
 934     animatedProperty.mPropertyName = std::string(weightNameBuffer);
 935
 936     animatedProperty.mKeyFrames = KeyFrames::New();
 937     for(uint32_t i = 0; i < input.mCount; ++i)
 938     {
 939       animatedProperty.mKeyFrames.Add(inputDataBuffer[i] / duration, outputDataBuffer[i * endWeightIndex + weightIndex]);
 940     }
 941
 942     animatedProperty.mTimePeriod = {0.f, duration};
 943   }
 944
 945   return duration;
 946 }
 947
 948 void ConvertAnimations(const gt::Document& doc, ConversionContext& cctx)
 949 {
 950   auto& output = cctx.mOutput;
 951
 952   output.mAnimationDefinitions.reserve(output.mAnimationDefinitions.size() + doc.mAnimations.size());
 953
 954   for(const auto& animation : doc.mAnimations)
 955   {
 956     AnimationDefinition animationDef;
 957
 958     if(!animation.mName.empty())
 959     {
 960       animationDef.mName = animation.mName;
 961     }
 962
 963     uint32_t numberOfProperties = 0u;
 964
 965     for(const auto& channel : animation.mChannels)
 966     {
 967       numberOfProperties += channel.mSampler->mOutput->mCount;
 968     }
 969     animationDef.mProperties.resize(numberOfProperties);
 970
 971     Index propertyIndex = 0u;
 972     for(const auto& channel : animation.mChannels)
 973     {
 974       std::string nodeName;
 975       if(!channel.mTarget.mNode->mName.empty())
 976       {
 977         nodeName = channel.mTarget.mNode->mName;
 978       }
 979       else
 980       {
 981         Index index = cctx.mNodeIndices.GetRuntimeId(channel.mTarget.mNode.GetIndex());
 982         nodeName    = cctx.mOutput.mScene.GetNode(index)->mName;
 983       }
 984
 985       float duration = 0.f;
 986
 987       switch(channel.mTarget.mPath)
 988       {
 989         case gt::Animation::Channel::Target::TRANSLATION:
 990         {
 991           AnimatedProperty& animatedProperty = animationDef.mProperties[propertyIndex];
 992
 993           animatedProperty.mNodeName     = nodeName;
 994           animatedProperty.mPropertyName = POSITION_PROPERTY;
 995
 996           animatedProperty.mKeyFrames = KeyFrames::New();
 997           duration                    = LoadKeyFrames<Vector3>(cctx.mPath, channel, animatedProperty.mKeyFrames, channel.mTarget.mPath);
 998
 999           animatedProperty.mTimePeriod = {0.f, duration};
1000           break;
1001         }
1002         case gt::Animation::Channel::Target::ROTATION:
1003         {
1004           AnimatedProperty& animatedProperty = animationDef.mProperties[propertyIndex];
1005
1006           animatedProperty.mNodeName     = nodeName;
1007           animatedProperty.mPropertyName = ORIENTATION_PROPERTY;
1008
1009           animatedProperty.mKeyFrames = KeyFrames::New();
1010           duration                    = LoadKeyFrames<Quaternion>(cctx.mPath, channel, animatedProperty.mKeyFrames, channel.mTarget.mPath);
1011
1012           animatedProperty.mTimePeriod = {0.f, duration};
1013           break;
1014         }
1015         case gt::Animation::Channel::Target::SCALE:
1016         {
1017           AnimatedProperty& animatedProperty = animationDef.mProperties[propertyIndex];
1018
1019           animatedProperty.mNodeName     = nodeName;
1020           animatedProperty.mPropertyName = SCALE_PROPERTY;
1021
1022           animatedProperty.mKeyFrames = KeyFrames::New();
1023           duration                    = LoadKeyFrames<Vector3>(cctx.mPath, channel, animatedProperty.mKeyFrames, channel.mTarget.mPath);
1024
1025           animatedProperty.mTimePeriod = {0.f, duration};
1026           break;
1027         }
1028         case gt::Animation::Channel::Target::WEIGHTS:
1029         {
1030           duration = LoadBlendShapeKeyFrames(cctx.mPath, channel, nodeName, propertyIndex, animationDef.mProperties);
1031
1032           break;
1033         }
1034         default:
1035         {
1036           // nothing to animate.
1037           break;
1038         }
1039       }
1040
1041       animationDef.mDuration = std::max(duration, animationDef.mDuration);
1042
1043       ++propertyIndex;
1044     }
1045
1046     output.mAnimationDefinitions.push_back(std::move(animationDef));
1047   }
1048 }
1049
1050 void ProcessSkins(const gt::Document& doc, ConversionContext& cctx)
1051 {
1052   // https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#skininversebindmatrices
1053   // If an inverseBindMatrices accessor was provided, we'll load the joint data from the buffer,
1054   // otherwise we'll set identity matrices for inverse bind pose.
1055   struct IInverseBindMatrixProvider
1056   {
1057     virtual ~IInverseBindMatrixProvider()
1058     {
1059     }
1060     virtual void Provide(Matrix& ibm) = 0;
1061   };
1062
1063   struct InverseBindMatrixAccessor : public IInverseBindMatrixProvider
1064   {
1065     std::ifstream  mStream;
1066     const uint32_t mElementSizeBytes;
1067
1068     InverseBindMatrixAccessor(const gt::Accessor& accessor, const std::string& path)
1069     : mStream(path + std::string(accessor.mBufferView->mBuffer->mUri), std::ios::binary),
1070       mElementSizeBytes(accessor.GetElementSizeBytes())
1071     {
1072       DALI_ASSERT_ALWAYS(mStream);
1073       DALI_ASSERT_DEBUG(accessor.mType == gt::AccessorType::MAT4 && accessor.mComponentType == gt::Component::FLOAT);
1074
1075       mStream.seekg(accessor.mBufferView->mByteOffset + accessor.mByteOffset);
1076     }
1077
1078     virtual void Provide(Matrix& ibm) override
1079     {
1080       DALI_ASSERT_ALWAYS(mStream.read(reinterpret_cast<char*>(ibm.AsFloat()), mElementSizeBytes));
1081     }
1082   };
1083
1084   struct DefaultInverseBindMatrixProvider : public IInverseBindMatrixProvider
1085   {
1086     virtual void Provide(Matrix& ibm) override
1087     {
1088       ibm = Matrix::IDENTITY;
1089     }
1090   };
1091
1092   auto& resources = cctx.mOutput.mResources;
1093   resources.mSkeletons.reserve(doc.mSkins.size());
1094
1095   for(auto& s : doc.mSkins)
1096   {
1097     std::unique_ptr<IInverseBindMatrixProvider> ibmProvider;
1098     if(s.mInverseBindMatrices)
1099     {
1100       ibmProvider.reset(new InverseBindMatrixAccessor(*s.mInverseBindMatrices, cctx.mPath));
1101     }
1102     else
1103     {
1104       ibmProvider.reset(new DefaultInverseBindMatrixProvider());
1105     }
1106
1107     SkeletonDefinition skeleton;
1108     if(s.mSkeleton.GetIndex() != INVALID_INDEX)
1109     {
1110       skeleton.mRootNodeIdx = cctx.mNodeIndices.GetRuntimeId(s.mSkeleton.GetIndex());
1111     }
1112
1113     skeleton.mJoints.resize(s.mJoints.size());
1114     auto iJoint = skeleton.mJoints.begin();
1115     for(auto& j : s.mJoints)
1116     {
1117       iJoint->mNodeIdx = cctx.mNodeIndices.GetRuntimeId(j.GetIndex());
1118
1119       ibmProvider->Provide(iJoint->mInverseBindMatrix);
1120
1121       ++iJoint;
1122     }
1123
1124     resources.mSkeletons.push_back(std::move(skeleton));
1125   }
1126 }
1127
1128 void ProduceShaders(ShaderDefinitionFactory& shaderFactory, SceneDefinition& scene)
1129 {
1130   for(size_t i0 = 0, i1 = scene.GetNodeCount(); i0 != i1; ++i0)
1131   {
1132     auto nodeDef = scene.GetNode(i0);
1133     if(auto renderable = nodeDef->mRenderable.get())
1134     {
1135       renderable->mShaderIdx = shaderFactory.ProduceShader(*nodeDef);
1136     }
1137   }
1138 }
1139
1140 void SetObjectReaders()
1141 {
1142   js::SetObjectReader(BUFFER_READER);
1143   js::SetObjectReader(BUFFER_VIEW_READER);
1144   js::SetObjectReader(BUFFER_VIEW_CLIENT_READER);
1145   js::SetObjectReader(COMPONENT_TYPED_BUFFER_VIEW_CLIENT_READER);
1146   js::SetObjectReader(ACCESSOR_SPARSE_READER);
1147   js::SetObjectReader(ACCESSOR_READER);
1148   js::SetObjectReader(IMAGE_READER);
1149   js::SetObjectReader(SAMPLER_READER);
1150   js::SetObjectReader(TEXURE_READER);
1151   js::SetObjectReader(TEXURE_INFO_READER);
1152   js::SetObjectReader(MATERIAL_PBR_READER);
1153   js::SetObjectReader(MATERIAL_READER);
1154   js::SetObjectReader(MESH_PRIMITIVE_READER);
1155   js::SetObjectReader(MESH_READER);
1156   js::SetObjectReader(SKIN_READER);
1157   js::SetObjectReader(CAMERA_PERSPECTIVE_READER);
1158   js::SetObjectReader(CAMERA_ORTHOGRAPHIC_READER);
1159   js::SetObjectReader(CAMERA_READER);
1160   js::SetObjectReader(NODE_READER);
1161   js::SetObjectReader(ANIMATION_SAMPLER_READER);
1162   js::SetObjectReader(ANIMATION_TARGET_READER);
1163   js::SetObjectReader(ANIMATION_CHANNEL_READER);
1164   js::SetObjectReader(ANIMATION_READER);
1165   js::SetObjectReader(SCENE_READER);
1166 }
1167
1168 void SetDefaultEnvironmentMap(const gt::Document& doc, ConversionContext& cctx)
1169 {
1170   EnvironmentDefinition envDef;
1171   envDef.mUseBrdfTexture = true;
1172   envDef.mIblIntensity = DEFAULT_INTENSITY;
1173   cctx.mOutput.mResources.mEnvironmentMaps.push_back({std::move(envDef), EnvironmentDefinition::Textures()});
1174 }
1175
1176 } // namespace
1177
1178 void LoadGltfScene(const std::string& url, ShaderDefinitionFactory& shaderFactory, LoadResult& params)
1179 {
1180   bool failed = false;
1181   auto js     = LoadTextFile(url.c_str(), &failed);
1182   if(failed)
1183   {
1184     throw std::runtime_error("Failed to load " + url);
1185   }
1186
1187   json::unique_ptr root(json_parse(js.c_str(), js.size()));
1188   if(!root)
1189   {
1190     throw std::runtime_error("Failed to parse " + url);
1191   }
1192
1193   static bool setObjectReaders = true;
1194   if(setObjectReaders)
1195   {
1196     // NOTE: only referencing own, anonymous namespace, const objects; the pointers will never need to change.
1197     SetObjectReaders();
1198     setObjectReaders = false;
1199   }
1200
1201   gt::Document doc;
1202
1203   auto& rootObj = js::Cast<json_object_s>(*root);
1204   auto  jsAsset = js::FindObjectChild("asset", rootObj);
1205
1206   auto jsAssetVersion = js::FindObjectChild("version", js::Cast<json_object_s>(*jsAsset));
1207   if(jsAssetVersion)
1208   {
1209     doc.mAsset.mVersion = js::Read::StringView(*jsAssetVersion);
1210   }
1211
1212   bool isMRendererModel(false);
1213   auto jsAssetGenerator = js::FindObjectChild("generator", js::Cast<json_object_s>(*jsAsset));
1214   if(jsAssetGenerator)
1215   {
1216     doc.mAsset.mGenerator = js::Read::StringView(*jsAssetGenerator);
1217     isMRendererModel      = (doc.mAsset.mGenerator.find(MRENDERER_MODEL_IDENTIFICATION) != std::string_view::npos);
1218   }
1219
1220
1221   gt::SetRefReaderObject(doc);
1222   DOCUMENT_READER.Read(rootObj, doc);
1223
1224   auto              path = url.substr(0, url.rfind('/') + 1);
1225   ConversionContext cctx{params, path, INVALID_INDEX};
1226
1227   ConvertMaterials(doc, cctx);
1228   ConvertMeshes(doc, cctx);
1229   ConvertNodes(doc, cctx, isMRendererModel);
1230   ConvertAnimations(doc, cctx);
1231   ProcessSkins(doc, cctx);
1232   ProduceShaders(shaderFactory, params.mScene);
1233   params.mScene.EnsureUniqueSkinningShaderInstances(params.mResources);
1234
1235   // Set Default Environment map
1236   SetDefaultEnvironmentMap(doc, cctx);
1237 }
1238
1239 } // namespace SceneLoader
1240 } // namespace Dali