PropertyTextureView.h

#pragma once
 
#include <CesiumGltf/Class.h>
#include <CesiumGltf/ClassProperty.h>
#include <CesiumGltf/ExtensionModelExtStructuralMetadata.h>
#include <CesiumGltf/Model.h>
#include <CesiumGltf/PropertyTexture.h>
#include <CesiumGltf/PropertyTexturePropertyView.h>
#include <CesiumGltf/PropertyTypeTraits.h>
#include <CesiumGltf/TextureView.h>
 
namespace CesiumGltf {
enum class PropertyTextureViewStatus {
  Valid,
 
  ErrorMissingMetadataExtension,
 
  ErrorMissingSchema,
 
  ErrorClassNotFound
};
 
class PropertyTextureView {
public:
  PropertyTextureView(
      const Model& model,
      const PropertyTexture& propertyTexture) noexcept;
 
  PropertyTextureViewStatus status() const noexcept { return this->_status; }
 
  const std::optional<std::string>& name() const noexcept {
    return _pPropertyTexture->name;
  }
 
  const Class* getClass() const noexcept { return _pClass; }
 
  const ClassProperty* getClassProperty(const std::string& propertyId) const;
 
  template <typename T, bool Normalized = false>
  PropertyTexturePropertyView<T, Normalized> getPropertyView(
      const std::string& propertyId,
      const TextureViewOptions& propertyOptions = TextureViewOptions()) const {
    if (this->_status != PropertyTextureViewStatus::Valid) {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorInvalidPropertyTexture);
    }
 
    const ClassProperty* pClassProperty = getClassProperty(propertyId);
    if (!pClassProperty) {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorNonexistentProperty);
    }
 
    return getPropertyViewImpl<T, Normalized>(
        propertyId,
        *pClassProperty,
        propertyOptions);
  }
 
  template <typename Callback>
  void getPropertyView(
      const std::string& propertyId,
      Callback&& callback,
      const TextureViewOptions& propertyOptions = TextureViewOptions()) const {
    if (this->_status != PropertyTextureViewStatus::Valid) {
      callback(
          propertyId,
          PropertyTexturePropertyView<uint8_t>(
              PropertyTexturePropertyViewStatus::ErrorInvalidPropertyTexture));
      return;
    }
 
    const ClassProperty* pClassProperty = getClassProperty(propertyId);
    if (!pClassProperty) {
      callback(
          propertyId,
          PropertyTexturePropertyView<uint8_t>(
              PropertyTexturePropertyViewStatus::ErrorNonexistentProperty));
      return;
    }
 
    PropertyType type = convertStringToPropertyType(pClassProperty->type);
    PropertyComponentType componentType = PropertyComponentType::None;
    if (pClassProperty->componentType) {
      componentType =
          convertStringToPropertyComponentType(*pClassProperty->componentType);
    }
 
    bool normalized = pClassProperty->normalized;
    if (normalized && !isPropertyComponentTypeInteger(componentType)) {
      // Only integer components may be normalized.
      callback(
          propertyId,
          PropertyTexturePropertyView<uint8_t>(
              PropertyTexturePropertyViewStatus::ErrorInvalidNormalization));
      return;
    }
 
    if (pClassProperty->array) {
      if (normalized) {
        getArrayPropertyViewImpl<Callback, true>(
            propertyId,
            *pClassProperty,
            type,
            componentType,
            std::forward<Callback>(callback),
            propertyOptions);
      } else {
        getArrayPropertyViewImpl<Callback, false>(
            propertyId,
            *pClassProperty,
            type,
            componentType,
            std::forward<Callback>(callback),
            propertyOptions);
      }
      return;
    }
 
    if (type == PropertyType::Scalar) {
      if (normalized) {
        getScalarPropertyViewImpl<Callback, true>(
            propertyId,
            *pClassProperty,
            componentType,
            std::forward<Callback>(callback),
            propertyOptions);
      } else {
        getScalarPropertyViewImpl<Callback, false>(
            propertyId,
            *pClassProperty,
            componentType,
            std::forward<Callback>(callback),
            propertyOptions);
      }
      return;
    }
 
    if (isPropertyTypeVecN(type)) {
      if (normalized) {
        getVecNPropertyViewImpl<Callback, true>(
            propertyId,
            *pClassProperty,
            type,
            componentType,
            std::forward<Callback>(callback),
            propertyOptions);
      } else {
        getVecNPropertyViewImpl<Callback, false>(
            propertyId,
            *pClassProperty,
            type,
            componentType,
            std::forward<Callback>(callback),
            propertyOptions);
      }
      return;
    }
 
    callback(
        propertyId,
        PropertyTexturePropertyView<uint8_t>(
            PropertyTexturePropertyViewStatus::ErrorUnsupportedProperty));
    return;
  }
 
  template <typename Callback>
  void forEachProperty(
      Callback&& callback,
      const TextureViewOptions& propertyOptions = TextureViewOptions()) const {
    for (const auto& property : this->_pClass->properties) {
      getPropertyView(
          property.first,
          std::forward<Callback>(callback),
          propertyOptions);
    }
  }
 
private:
  template <typename T, bool Normalized>
  PropertyTexturePropertyView<T, Normalized> getPropertyViewImpl(
      const std::string& propertyId,
      const ClassProperty& classProperty,
      const TextureViewOptions& propertyOptions) const {
    auto propertyTexturePropertyIter =
        _pPropertyTexture->properties.find(propertyId);
    if (propertyTexturePropertyIter == _pPropertyTexture->properties.end()) {
      if (!classProperty.required && classProperty.defaultProperty) {
        // If the property was omitted from the property texture, it is still
        // technically valid if it specifies a default value. Create a view that
        // just returns the default value.
        return PropertyTexturePropertyView<T, Normalized>(classProperty);
      }
 
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorNonexistentProperty);
    }
 
    const PropertyTextureProperty& propertyTextureProperty =
        propertyTexturePropertyIter->second;
 
    if constexpr (IsMetadataScalar<T>::value) {
      return createScalarPropertyView<T, Normalized>(
          classProperty,
          propertyTextureProperty,
          propertyOptions);
    }
 
    if constexpr (IsMetadataVecN<T>::value) {
      return createVecNPropertyView<T, Normalized>(
          classProperty,
          propertyTextureProperty,
          propertyOptions);
    }
 
    if constexpr (IsMetadataArray<T>::value) {
      return createArrayPropertyView<
          typename MetadataArrayType<T>::type,
          Normalized>(classProperty, propertyTextureProperty, propertyOptions);
    }
  }
 
  template <typename Callback, bool Normalized>
  void getArrayPropertyViewImpl(
      const std::string& propertyId,
      const ClassProperty& classProperty,
      PropertyType type,
      PropertyComponentType componentType,
      Callback&& callback,
      const TextureViewOptions& propertyOptions) const {
    // Only scalar arrays are supported.
    if (type != PropertyType::Scalar) {
      callback(
          propertyId,
          PropertyTexturePropertyView<uint8_t>(
              PropertyTexturePropertyViewStatus::ErrorUnsupportedProperty));
      return;
    }
 
    int64_t count = classProperty.count.value_or(0);
    if (count <= 0 || count > 4) {
      callback(
          propertyId,
          PropertyTexturePropertyView<uint8_t>(
              PropertyTexturePropertyViewStatus::ErrorUnsupportedProperty));
      return;
    }
 
    switch (componentType) {
    case PropertyComponentType::Int8:
      callback(
          propertyId,
          getPropertyViewImpl<PropertyArrayView<int8_t>, Normalized>(
              propertyId,
              classProperty,
              propertyOptions));
      break;
    case PropertyComponentType::Uint8:
      callback(
          propertyId,
          getPropertyViewImpl<PropertyArrayView<uint8_t>, Normalized>(
              propertyId,
              classProperty,
              propertyOptions));
      break;
    case PropertyComponentType::Int16:
      callback(
          propertyId,
          getPropertyViewImpl<PropertyArrayView<int16_t>, Normalized>(
              propertyId,
              classProperty,
              propertyOptions));
      break;
    case PropertyComponentType::Uint16:
      callback(
          propertyId,
          getPropertyViewImpl<PropertyArrayView<uint16_t>, Normalized>(
              propertyId,
              classProperty,
              propertyOptions));
      break;
    default:
      callback(
          propertyId,
          PropertyTexturePropertyView<uint8_t>(
              PropertyTexturePropertyViewStatus::ErrorUnsupportedProperty));
      break;
    }
  }
 
  template <typename Callback, bool Normalized>
  void getScalarPropertyViewImpl(
      const std::string& propertyId,
      const ClassProperty& classProperty,
      PropertyComponentType componentType,
      Callback&& callback,
      const TextureViewOptions& propertyOptions) const {
    switch (componentType) {
    case PropertyComponentType::Int8:
      callback(
          propertyId,
          getPropertyViewImpl<int8_t, Normalized>(
              propertyId,
              classProperty,
              propertyOptions));
      return;
    case PropertyComponentType::Uint8:
      callback(
          propertyId,
          getPropertyViewImpl<uint8_t, Normalized>(
              propertyId,
              classProperty,
              propertyOptions));
      return;
    case PropertyComponentType::Int16:
      callback(
          propertyId,
          getPropertyViewImpl<int16_t, Normalized>(
              propertyId,
              classProperty,
              propertyOptions));
      return;
    case PropertyComponentType::Uint16:
      callback(
          propertyId,
          getPropertyViewImpl<uint16_t, Normalized>(
              propertyId,
              classProperty,
              propertyOptions));
      break;
    case PropertyComponentType::Int32:
      callback(
          propertyId,
          getPropertyViewImpl<int32_t, Normalized>(
              propertyId,
              classProperty,
              propertyOptions));
      break;
    case PropertyComponentType::Uint32:
      callback(
          propertyId,
          getPropertyViewImpl<uint32_t, Normalized>(
              propertyId,
              classProperty,
              propertyOptions));
      break;
    case PropertyComponentType::Float32:
      callback(
          propertyId,
          getPropertyViewImpl<float, false>(
              propertyId,
              classProperty,
              propertyOptions));
      break;
    default:
      callback(
          propertyId,
          PropertyTexturePropertyView<uint8_t>(
              PropertyTexturePropertyViewStatus::ErrorUnsupportedProperty));
      break;
    }
  }
 
  template <typename Callback, glm::length_t N, bool Normalized>
  void getVecNPropertyViewImpl(
      const std::string& propertyId,
      const ClassProperty& classProperty,
      PropertyComponentType componentType,
      Callback&& callback,
      const TextureViewOptions& propertyOptions) const {
    switch (componentType) {
    case PropertyComponentType::Int8:
      callback(
          propertyId,
          getPropertyViewImpl<glm::vec<N, int8_t>, Normalized>(
              propertyId,
              classProperty,
              propertyOptions));
      break;
    case PropertyComponentType::Uint8:
      callback(
          propertyId,
          getPropertyViewImpl<glm::vec<N, uint8_t>, Normalized>(
              propertyId,
              classProperty,
              propertyOptions));
      break;
    case PropertyComponentType::Int16:
      if constexpr (N == 2) {
        callback(
            propertyId,
            getPropertyViewImpl<glm::vec<N, int16_t>, Normalized>(
                propertyId,
                classProperty,
                propertyOptions));
        break;
      }
      [[fallthrough]];
    case PropertyComponentType::Uint16:
      if constexpr (N == 2) {
        callback(
            propertyId,
            getPropertyViewImpl<glm::vec<N, uint16_t>, Normalized>(
                propertyId,
                classProperty,
                propertyOptions));
        break;
      }
      [[fallthrough]];
    default:
      callback(
          propertyId,
          PropertyTexturePropertyView<uint8_t>(
              PropertyTexturePropertyViewStatus::ErrorUnsupportedProperty));
      break;
    }
  }
 
  template <typename Callback, bool Normalized>
  void getVecNPropertyViewImpl(
      const std::string& propertyId,
      const ClassProperty& classProperty,
      PropertyType type,
      PropertyComponentType componentType,
      Callback&& callback,
      const TextureViewOptions& propertyOptions) const {
    const glm::length_t N = getDimensionsFromPropertyType(type);
    switch (N) {
    case 2:
      getVecNPropertyViewImpl<Callback, 2, Normalized>(
          propertyId,
          classProperty,
          componentType,
          std::forward<Callback>(callback),
          propertyOptions);
      break;
    case 3:
      getVecNPropertyViewImpl<Callback, 3, Normalized>(
          propertyId,
          classProperty,
          componentType,
          std::forward<Callback>(callback),
          propertyOptions);
      break;
    case 4:
      getVecNPropertyViewImpl<Callback, 4, Normalized>(
          propertyId,
          classProperty,
          componentType,
          std::forward<Callback>(callback),
          propertyOptions);
      break;
    default:
      callback(
          propertyId,
          PropertyTexturePropertyView<uint8_t>(
              PropertyTexturePropertyViewStatus::ErrorTypeMismatch));
      break;
    }
  }
 
  template <typename T, bool Normalized>
  PropertyTexturePropertyView<T, Normalized> createScalarPropertyView(
      const ClassProperty& classProperty,
      [[maybe_unused]] const PropertyTextureProperty& propertyTextureProperty,
      const TextureViewOptions& propertyOptions) const {
    if (classProperty.array) {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorArrayTypeMismatch);
    }
 
    const PropertyType type = convertStringToPropertyType(classProperty.type);
    if (!canRepresentPropertyType<T>(type)) {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorTypeMismatch);
    }
 
    PropertyComponentType componentType = convertStringToPropertyComponentType(
        classProperty.componentType.value_or(""));
    const CesiumGltf::Enum* pEnumDefinition = nullptr;
 
    if (type == PropertyType::Enum && classProperty.enumType) {
      const auto& enumDefinitionIt =
          this->_pEnumDefinitions->find(*classProperty.enumType);
      if (enumDefinitionIt == this->_pEnumDefinitions->end()) {
        return PropertyTexturePropertyView<T, Normalized>(
            PropertyTexturePropertyViewStatus::ErrorInvalidEnum);
      }
 
      componentType = convertStringToPropertyComponentType(
          enumDefinitionIt->second.valueType);
      pEnumDefinition = &enumDefinitionIt->second;
 
      if (componentType == PropertyComponentType::Float32 ||
          componentType == PropertyComponentType::Float64) {
        return PropertyTexturePropertyView<T, Normalized>(
            PropertyTexturePropertyViewStatus::ErrorInvalidEnum);
      }
    } else if (type == PropertyType::Enum) {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorInvalidEnum);
    }
 
    if (TypeToPropertyType<T>::component != componentType) {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorComponentTypeMismatch);
    }
 
    if (classProperty.normalized != Normalized) {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorNormalizationMismatch);
    }
 
    // Only up to four bytes of image data are supported.
    if constexpr (sizeof(T) <= 4) {
      return createPropertyViewImpl<T, Normalized>(
          classProperty,
          propertyTextureProperty,
          sizeof(T),
          propertyOptions,
          pEnumDefinition);
    } else {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorUnsupportedProperty);
    }
  }
 
  template <typename T, bool Normalized>
  PropertyTexturePropertyView<T, Normalized> createVecNPropertyView(
      const ClassProperty& classProperty,
      [[maybe_unused]] const PropertyTextureProperty& propertyTextureProperty,
      [[maybe_unused]] const TextureViewOptions& propertyOptions) const {
    if (classProperty.array) {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorArrayTypeMismatch);
    }
 
    const PropertyType type = convertStringToPropertyType(classProperty.type);
    if (!canRepresentPropertyType<T>(type)) {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorTypeMismatch);
    }
 
    const PropertyComponentType componentType =
        convertStringToPropertyComponentType(
            classProperty.componentType.value_or(""));
    if (TypeToPropertyType<T>::component != componentType) {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorComponentTypeMismatch);
    }
 
    if (classProperty.normalized != Normalized) {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorNormalizationMismatch);
    }
 
    // Only up to four bytes of image data are supported.
    if constexpr (sizeof(T) <= 4) {
      return createPropertyViewImpl<T, Normalized>(
          classProperty,
          propertyTextureProperty,
          sizeof(T),
          propertyOptions,
          nullptr);
    } else {
      return PropertyTexturePropertyView<T, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorUnsupportedProperty);
    }
  }
 
  template <typename T, bool Normalized>
  PropertyTexturePropertyView<PropertyArrayView<T>, Normalized>
  createArrayPropertyView(
      const ClassProperty& classProperty,
      [[maybe_unused]] const PropertyTextureProperty& propertyTextureProperty,
      [[maybe_unused]] const TextureViewOptions& propertyOptions) const {
    if (!classProperty.array) {
      return PropertyTexturePropertyView<PropertyArrayView<T>, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorArrayTypeMismatch);
    }
 
    const PropertyType type = convertStringToPropertyType(classProperty.type);
    if (!canRepresentPropertyType<T>(type)) {
      return PropertyTexturePropertyView<PropertyArrayView<T>, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorTypeMismatch);
    }
 
    PropertyComponentType componentType = convertStringToPropertyComponentType(
        classProperty.componentType.value_or(""));
    const CesiumGltf::Enum* pEnumDefinition = nullptr;
 
    if (type == PropertyType::Enum && classProperty.enumType) {
      const auto& enumDefinitionIt =
          this->_pEnumDefinitions->find(*classProperty.enumType);
      if (enumDefinitionIt == this->_pEnumDefinitions->end()) {
        return PropertyTexturePropertyView<PropertyArrayView<T>, Normalized>(
            PropertyTexturePropertyViewStatus::ErrorInvalidEnum);
      }
 
      componentType = convertStringToPropertyComponentType(
          enumDefinitionIt->second.valueType);
      pEnumDefinition = &enumDefinitionIt->second;
 
      if (componentType == PropertyComponentType::Float32 ||
          componentType == PropertyComponentType::Float64) {
        return PropertyTexturePropertyView<PropertyArrayView<T>, Normalized>(
            PropertyTexturePropertyViewStatus::ErrorInvalidEnum);
      }
    } else if (type == PropertyType::Enum) {
      return PropertyTexturePropertyView<PropertyArrayView<T>, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorInvalidEnum);
    }
 
    if (TypeToPropertyType<T>::component != componentType) {
      return PropertyTexturePropertyView<PropertyArrayView<T>, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorComponentTypeMismatch);
    }
 
    if (classProperty.normalized != Normalized) {
      return PropertyTexturePropertyView<PropertyArrayView<T>, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorNormalizationMismatch);
    }
 
    // Only scalar arrays are supported. The scalar component type must not
    // exceed two bytes.
    if constexpr (IsMetadataScalar<T>::value && sizeof(T) <= 4) {
      // Only up to four elements are supported.
      size_t count = static_cast<size_t>(classProperty.count.value_or(0));
      if (count <= 0 || count > 4) {
        return PropertyTexturePropertyView<PropertyArrayView<T>, Normalized>(
            PropertyTexturePropertyViewStatus::ErrorUnsupportedProperty);
      }
 
      if (count * sizeof(T) > 4) {
        return PropertyTexturePropertyView<PropertyArrayView<T>, Normalized>(
            PropertyTexturePropertyViewStatus::ErrorUnsupportedProperty);
      }
 
      return createPropertyViewImpl<PropertyArrayView<T>, Normalized>(
          classProperty,
          propertyTextureProperty,
          count * sizeof(T),
          propertyOptions,
          pEnumDefinition);
    } else {
      return PropertyTexturePropertyView<PropertyArrayView<T>, Normalized>(
          PropertyTexturePropertyViewStatus::ErrorUnsupportedProperty);
    }
  }
 
  template <typename T, bool Normalized>
  PropertyTexturePropertyView<T, Normalized> createPropertyViewImpl(
      const ClassProperty& classProperty,
      const PropertyTextureProperty& propertyTextureProperty,
      size_t elementSize,
      const TextureViewOptions& propertyOptions,
      const CesiumGltf::Enum* pEnumDefinition) const {
    int32_t samplerIndex;
    int32_t imageIndex;
 
    auto status =
        getTextureSafe(propertyTextureProperty.index, samplerIndex, imageIndex);
 
    if (status != PropertyTexturePropertyViewStatus::Valid) {
      return PropertyTexturePropertyView<T, Normalized>(status);
    }
 
    status = checkSampler(samplerIndex);
    if (status != PropertyTexturePropertyViewStatus::Valid) {
      return PropertyTexturePropertyView<T, Normalized>(status);
    }
 
    status = checkImage(imageIndex);
    if (status != PropertyTexturePropertyViewStatus::Valid) {
      return PropertyTexturePropertyView<T, Normalized>(status);
    }
 
    const CesiumUtility::IntrusivePointer<ImageAsset>& pImage =
        _pModel->images[static_cast<size_t>(imageIndex)].pAsset;
    const std::vector<int64_t>& channels = propertyTextureProperty.channels;
 
    status = checkChannels(channels, *pImage);
    if (status != PropertyTexturePropertyViewStatus::Valid) {
      return PropertyTexturePropertyView<T, Normalized>(status);
    }
 
    if (channels.size() * static_cast<size_t>(pImage->bytesPerChannel) !=
        elementSize) {
      return PropertyTexturePropertyViewStatus::ErrorChannelsAndTypeMismatch;
    }
 
    if constexpr (!Normalized) {
      if (pEnumDefinition != nullptr) {
        return PropertyTexturePropertyView<T, Normalized>(
            propertyTextureProperty,
            classProperty,
            pEnumDefinition,
            _pModel->samplers[static_cast<size_t>(samplerIndex)],
            *pImage,
            propertyOptions);
      }
    }
 
    return PropertyTexturePropertyView<T, Normalized>(
        propertyTextureProperty,
        classProperty,
        _pModel->samplers[static_cast<size_t>(samplerIndex)],
        *pImage,
        propertyOptions);
  }
 
  PropertyViewStatusType getTextureSafe(
      const int32_t textureIndex,
      int32_t& samplerIndex,
      int32_t& imageIndex) const noexcept;
 
  PropertyViewStatusType
  checkSampler(const int32_t samplerIndex) const noexcept;
 
  PropertyViewStatusType checkImage(const int32_t imageIndex) const noexcept;
 
  PropertyViewStatusType checkChannels(
      const std::vector<int64_t>& channels,
      const ImageAsset& image) const noexcept;
 
  const Model* _pModel;
  const PropertyTexture* _pPropertyTexture;
  const Class* _pClass;
  const std::unordered_map<std::string, CesiumGltf::Enum>* _pEnumDefinitions;
 
  PropertyTextureViewStatus _status;
};
} // namespace CesiumGltf