Added Streaming buffer

2 files changed, 195 insertions, 0 deletions

diff --git a/Graphics/GraphicsTools/CMakeLists.txt b/Graphics/GraphicsTools/CMakeLists.txt
index 5858475b..7d806761 100644
--- a/Graphics/GraphicsTools/CMakeLists.txt
+++ b/Graphics/GraphicsTools/CMakeLists.txt
@@ -11,6 +11,7 @@ set(INTERFACE
     interface/ScopedQueryHelper.hpp
     interface/ScreenCapture.hpp
     interface/ShaderMacroHelper.hpp
+    interface/StreamingBuffer.hpp
     interface/TextureUploader.hpp
     interface/TextureUploaderBase.hpp
 )
diff --git a/Graphics/GraphicsTools/interface/StreamingBuffer.hpp b/Graphics/GraphicsTools/interface/StreamingBuffer.hpp
new file mode 100644
index 00000000..65cad5e5
--- /dev/null
+++ b/Graphics/GraphicsTools/interface/StreamingBuffer.hpp
@@ -0,0 +1,194 @@
+/*
+ *  Copyright 2019-2020 Diligent Graphics LLC
+ *  Copyright 2015-2019 Egor Yusov
+ *  
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *  
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *  
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ *  In no event and under no legal theory, whether in tort (including negligence), 
+ *  contract, or otherwise, unless required by applicable law (such as deliberate 
+ *  and grossly negligent acts) or agreed to in writing, shall any Contributor be
+ *  liable for any damages, including any direct, indirect, special, incidental, 
+ *  or consequential damages of any character arising as a result of this License or 
+ *  out of the use or inability to use the software (including but not limited to damages 
+ *  for loss of goodwill, work stoppage, computer failure or malfunction, or any and 
+ *  all other commercial damages or losses), even if such Contributor has been advised 
+ *  of the possibility of such damages.
+ */
+
+#pragma once
+
+#include <functional>
+#include <vector>
+#include <string>
+
+#include "../../GraphicsEngine/interface/RenderDevice.h"
+#include "../../GraphicsEngine/interface/DeviceContext.h"
+#include "../../GraphicsEngine/interface/Buffer.h"
+#include "../../../Common/interface/RefCntAutoPtr.hpp"
+#include "MapHelper.hpp"
+
+namespace Diligent
+{
+
+struct StreamingBufferCreateInfo
+{
+    IRenderDevice*                pDevice = nullptr;
+    BufferDesc                    BuffDesc;
+    std::function<void(IBuffer*)> OnBufferResizeCallback = nullptr;
+    Uint32                        NumContexts            = 1;
+    bool                          AllowPersistentMapping = false;
+};
+
+class StreamingBuffer
+{
+public:
+    StreamingBuffer() noexcept
+    {}
+
+    StreamingBuffer(const StreamingBufferCreateInfo& CI) :
+        m_UsePersistentMap{CI.AllowPersistentMapping && (CI.pDevice->GetDeviceCaps().IsVulkanDevice() || CI.pDevice->GetDeviceCaps().DevType == RENDER_DEVICE_TYPE_D3D12)},
+        m_BufferSize{CI.BuffDesc.uiSizeInBytes},
+        m_OnBufferResizeCallback{CI.OnBufferResizeCallback},
+        m_MapInfo(CI.NumContexts)
+    {
+        VERIFY_EXPR(CI.pDevice != nullptr);
+        VERIFY_EXPR(CI.BuffDesc.Usage == USAGE_DYNAMIC);
+        CI.pDevice->CreateBuffer(CI.BuffDesc, nullptr, &m_pBuffer);
+        VERIFY_EXPR(m_pBuffer);
+        if (m_OnBufferResizeCallback)
+            m_OnBufferResizeCallback(m_pBuffer);
+    }
+
+    StreamingBuffer(const StreamingBuffer&) = delete;
+    StreamingBuffer& operator=(const StreamingBuffer&) = delete;
+
+    StreamingBuffer(StreamingBuffer&&) = default;
+    StreamingBuffer& operator=(StreamingBuffer&&) = default;
+
+    ~StreamingBuffer()
+    {
+        for (const auto& mapInfo : m_MapInfo)
+        {
+            VERIFY(!mapInfo.m_MappedData, "Destroying streaming buffer that is still mapped");
+        }
+    }
+
+    // Returns offset of the allocated region
+    Uint32 Map(IDeviceContext* pCtx, IRenderDevice* pDevice, Uint32 Size, size_t CtxNum = 0)
+    {
+        VERIFY_EXPR(Size > 0);
+
+        auto& MapInfo = m_MapInfo[CtxNum];
+        // Check if there is enough space in the buffer
+        if (MapInfo.m_CurrOffset + Size > m_BufferSize)
+        {
+            // Unmap the buffer
+            Flush(CtxNum);
+            VERIFY_EXPR(MapInfo.m_CurrOffset == 0);
+
+            if (Size > m_BufferSize)
+            {
+                while (m_BufferSize < Size)
+                    m_BufferSize *= 2;
+
+                auto BuffDesc          = m_pBuffer->GetDesc();
+                BuffDesc.uiSizeInBytes = m_BufferSize;
+                // BuffDesc.Name becomes invalid after old buffer is released
+                std::string Name = BuffDesc.Name;
+                BuffDesc.Name    = Name.c_str();
+
+                m_pBuffer.Release();
+                pDevice->CreateBuffer(BuffDesc, nullptr, &m_pBuffer);
+                if (m_OnBufferResizeCallback)
+                    m_OnBufferResizeCallback(m_pBuffer);
+
+                LOG_INFO_MESSAGE("Extended streaming buffer '", BuffDesc.Name, "' to ", m_BufferSize, " bytes");
+            }
+        }
+
+        if (!m_UsePersistentMap)
+        {
+            VERIFY(MapInfo.m_MappedData == nullptr, "Streaming buffer must be unmapped before it can be mapped next time when persistent mapping is not used");
+        }
+
+        if (MapInfo.m_MappedData == nullptr)
+        {
+            // If current offset is zero, we are mapping the buffer for the first time after it has been Reseted. Use MAP_FLAG_DISCARD flag.
+            // Otherwise use MAP_FLAG_NO_OVERWRITE flag.
+            MapInfo.m_MappedData.Map(pCtx, m_pBuffer, MAP_WRITE, MapInfo.m_CurrOffset == 0 ? MAP_FLAG_DISCARD : MAP_FLAG_NO_OVERWRITE);
+            VERIFY_EXPR(MapInfo.m_MappedData);
+        }
+
+        auto Offset = MapInfo.m_CurrOffset;
+        // Update offset
+        MapInfo.m_CurrOffset += Size;
+        return Offset;
+    }
+
+    Uint32 Update(IDeviceContext* pCtx, IRenderDevice* pDevice, const void* pData, Uint32 Size, size_t CtxNum = 0)
+    {
+        VERIFY_EXPR(pData != nullptr);
+        auto  Offset      = Map(pCtx, pDevice, Size, CtxNum);
+        auto* pCPUAddress = reinterpret_cast<Uint8*>(GetMappedCPUAddress(CtxNum)) + Offset;
+        memcpy(pCPUAddress, pData, Size);
+        Unmap(CtxNum);
+
+        return Offset;
+    }
+
+    void Unmap(size_t CtxNum = 0)
+    {
+        if (!m_UsePersistentMap)
+        {
+            m_MapInfo[CtxNum].m_MappedData.Unmap();
+        }
+    }
+
+    void Flush(size_t CtxNum = 0)
+    {
+        m_MapInfo[CtxNum].m_MappedData.Unmap();
+        m_MapInfo[CtxNum].m_CurrOffset = 0;
+    }
+
+    void Reset()
+    {
+        for (Uint32 ctx = 0; ctx < m_MapInfo.size(); ++ctx)
+            Flush(ctx);
+    }
+
+    IBuffer* GetBuffer() const { return m_pBuffer.RawPtr<IBuffer>(); }
+
+    void* GetMappedCPUAddress(size_t CtxNum = 0)
+    {
+        return m_MapInfo[CtxNum].m_MappedData;
+    }
+
+private:
+    bool m_UsePersistentMap = false;
+
+    Uint32 m_BufferSize = 0;
+
+    RefCntAutoPtr<IBuffer> m_pBuffer;
+
+    std::function<void(IBuffer*)> m_OnBufferResizeCallback;
+
+    struct MapInfo
+    {
+        MapHelper<Uint8> m_MappedData;
+        Uint32           m_CurrOffset = 0;
+    };
+    // We need to keep track of mapped data for every context
+    std::vector<MapInfo> m_MapInfo;
+};
+
+} // namespace Diligent