Method ProcessInputParameter

Hydrogent/src/HnMaterialNetwork.cpp:824–910

void HnMaterialNetwork::ProcessInputParameter(const pxr::HdMaterialNetwork2& Network,
                                              const pxr::HdMaterialNode2&    Node,
                                              const pxr::TfToken&            ParamName,
                                              pxr::SdfPathSet&               VisitedNodes)
{
    pxr::SdrRegistry& ShaderReg = pxr::SdrRegistry::GetInstance();

    // Resolve what is connected to this param (eg. primvar, texture, nothing)
    // and then make the correct HdSt_MaterialParam for it.
    auto const& conn_it = Node.inputConnections.find(ParamName);
    if (conn_it != Node.inputConnections.end())
    {
        const std::vector<pxr::HdMaterialConnection2>& Connections = conn_it->second;
        if (!Connections.empty())
        {
            // Find the node that is connected to this input
            const pxr::HdMaterialConnection2& Conn  = Connections.front();
            auto const&                       up_it = Network.nodes.find(Conn.upstreamNode);

            if (up_it != Network.nodes.end())
            {
                const pxr::SdfPath&         UpstreamPath       = up_it->first;
                const pxr::TfToken&         UpstreamOutputName = Conn.upstreamOutputName;
                const pxr::HdMaterialNode2& UpstreamNode       = up_it->second;

                pxr::SdrShaderNodeConstPtr UpstreamSdr =
                    ShaderReg.GetShaderNodeByIdentifier(
                        UpstreamNode.nodeTypeId,
                        {pxr::HioGlslfxTokens->glslfx, HnMaterialPrivateTokens->mtlx});

                if (UpstreamSdr)
                {
                    pxr::TfToken SdrRole{UpstreamSdr->GetRole()};
                    if (SdrRole == pxr::SdrNodeRole->Texture)
                    {
                        AddTextureParam(
                            Network,
                            UpstreamNode,
                            Node,
                            UpstreamPath,
                            UpstreamOutputName,
                            ParamName,
                            VisitedNodes);
                        return;
                    }
                    else if (SdrRole == pxr::SdrNodeRole->Primvar)
                    {
                        AddPrimvarReaderParam(
                            Network,
                            UpstreamNode,
                            UpstreamPath,
                            ParamName,
                            VisitedNodes);
                        return;
                    }
                    else if (SdrRole == pxr::SdrNodeRole->Field)
                    {
                        AddFieldReaderParam(