Method UpdateIndexBuffer

Hydrogent/src/HnMesh.cpp:1170–1237

}

void HnMesh::UpdateIndexBuffer(HnRenderDelegate& RenderDelegate)
{
    VERIFY_EXPR(m_StagingIndexData);

    auto PrepareIndexBuffer = [&](const char*           BufferName,
                                  const void*           pData,
                                  size_t                DataSize,
                                  IBufferSuballocation* pSuballocation) {
        const std::string Name = GetId().GetString() + " - " + BufferName;

        IDeviceContext* pCtx = RenderDelegate.GetDeviceContext();
        if (pSuballocation == nullptr)
        {
            BufferDesc Desc{
                Name.c_str(),
                DataSize,
                BIND_INDEX_BUFFER,
                USAGE_IMMUTABLE,
            };
            BufferData InitData{pData, Desc.Size};

            const RenderDeviceX_N& Device{RenderDelegate.GetDevice()};
            RefCntAutoPtr<IBuffer> pBuffer = Device.CreateBuffer(Desc, &InitData);

            StateTransitionDesc Barrier{pBuffer, RESOURCE_STATE_UNKNOWN, RESOURCE_STATE_INDEX_BUFFER, STATE_TRANSITION_FLAG_UPDATE_STATE};
            pCtx->TransitionResourceStates(1, &Barrier);

            return pBuffer;
        }
        else
        {
            RefCntAutoPtr<IBuffer> pBuffer{pSuballocation->GetBuffer()};
            VERIFY_EXPR(pSuballocation->GetSize() == DataSize);
            pCtx->UpdateBuffer(pBuffer, pSuballocation->GetOffset(), DataSize, pData, RESOURCE_STATE_TRANSITION_MODE_TRANSITION);
            return pBuffer;
        }
    };

    if (!m_StagingIndexData->Faces.Indices.empty())
    {
        VERIFY_EXPR(m_IndexData.NumFaceTriangles == static_cast<size_t>(m_StagingIndexData->Faces.Indices.size()));
        static_assert(sizeof(m_StagingIndexData->Faces.Indices[0]) == sizeof(Uint32) * 3, "Unexpected triangle data size");
        m_IndexData.Faces = PrepareIndexBuffer("Triangle Index Buffer",
                                               m_StagingIndexData->Faces.Indices.data(),
                                               m_IndexData.NumFaceTriangles * sizeof(Uint32) * 3,
                                               m_IndexData.FaceAllocation);
    }

    if (!m_StagingIndexData->MeshEdgeIndices.empty())
    {
        VERIFY_EXPR(m_IndexData.NumEdges == static_cast<Uint32>(m_StagingIndexData->MeshEdgeIndices.size()));
        m_IndexData.Edges = PrepareIndexBuffer("Edge Index Buffer",
                                               m_StagingIndexData->MeshEdgeIndices.data(),
                                               m_IndexData.NumEdges * sizeof(Uint32) * 2,
                                               m_IndexData.EdgeAllocation);
    }

    if (!m_StagingIndexData->PointIndices.empty())