Method LoadMaterialsForScene

samples/renderer/NtcMaterialLoader.cpp:1313–1450

}

bool NtcMaterialLoader::LoadMaterialsForScene(donut::engine::Scene& scene, std::filesystem::path const& materialDir, 
    bool enableInferenceOnLoad, bool enableBlockCompression, bool enableInferenceOnSample,
    bool enableInferenceOnFeedback, std::shared_ptr<nvfeedback::FeedbackManager> feedbackManager)
{
    using namespace std::chrono;
    time_point start = steady_clock::now();

    uint64_t totalFileSize = 0;
    uint64_t totalPixels = 0;
    int materialCount = 0;
    m_weightTypeHistogram.fill(0);

    std::vector<std::shared_ptr<engine::Material>> materials;
    for (std::shared_ptr<engine::Material> const& material : scene.GetSceneGraph()->GetMaterials())
        materials.push_back(material);

    std::unordered_map<std::string, std::shared_ptr<NtcMaterial>> ntcMaterialCache; // ntcData.ToString() -> NtcMaterial

    for (std::shared_ptr<engine::Material> const& material : materials)
    {
        std::shared_ptr<NtcMaterial> ntcMaterial = std::static_pointer_cast<NtcMaterial>(material);

        fs::path modelFileName = material->modelFileName;
        fs::path currentMaterialDir = materialDir.empty() ? modelFileName.parent_path() : materialDir;

        // Find a single NTC file that contains channels for all textures for this material.
        // In a general case, there may be multiple different files used in a single material,
        // but our GLTF preparation script only uses one, and we only support one in this renderer.
        // Also derive the channel mapping: where to source the channels for albedo, roughness, etc.
        donut::engine::FilePathOrInlineData ntcData;
        MaterialChannelMap channelMap;
        GetNtcDataSourceAndChannelMap(*ntcMaterial, ntcData, channelMap);

        // No NTC data found, skip the material
        if (!ntcData)
            continue;

        auto cacheIterator = ntcMaterialCache.find(ntcData.ToString());
        if (cacheIterator != ntcMaterialCache.end())
        {
            auto previouslyLoadedMaterial = cacheIterator->second;

            // Copy over all the properties that we touch when decoding NTC materials,
            // but not the entire material: some flags or parameters might be different.
            ntcMaterial->ntcConstantBuffer = previouslyLoadedMaterial->ntcConstantBuffer;
            ntcMaterial->ntcWeightsBuffer = previouslyLoadedMaterial->ntcWeightsBuffer;
            ntcMaterial->ntcLatentsTexture = previouslyLoadedMaterial->ntcLatentsTexture;
            ntcMaterial->weightType = previouslyLoadedMaterial->weightType;
            ntcMaterial->baseOrDiffuseTexture = previouslyLoadedMaterial->baseOrDiffuseTexture;
            ntcMaterial->metalRoughOrSpecularTexture = previouslyLoadedMaterial->metalRoughOrSpecularTexture;
            ntcMaterial->normalTexture = previouslyLoadedMaterial->normalTexture;
            ntcMaterial->emissiveTexture = previouslyLoadedMaterial->emissiveTexture;
            ntcMaterial->occlusionTexture = previouslyLoadedMaterial->occlusionTexture;
            ntcMaterial->transmissionTexture = previouslyLoadedMaterial->transmissionTexture;
            ntcMaterial->opacityTexture = previouslyLoadedMaterial->opacityTexture;
            ntcMaterial->metalnessInRedChannel = previouslyLoadedMaterial->metalnessInRedChannel;
            ntcMaterial->baseOrDiffuseTextureFeedback = previouslyLoadedMaterial->baseOrDiffuseTextureFeedback;
            ntcMaterial->metalRoughOrSpecularTextureFeedback = previouslyLoadedMaterial->metalRoughOrSpecularTextureFeedback;