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Source/Engine/GraphicsDevice/DirectX/DX12/CommandAllocatorPoolDX12.cpp

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+#if GRAPHICS_API_DIRECTX12
+
+#include "CommandAllocatorPoolDX12.h"
+#include "GPUDeviceDX12.h"
+#include "Engine/Threading/Threading.h"
+#include "Engine/GraphicsDevice/DirectX/RenderToolsDX.h"
+
+CommandAllocatorPoolDX12::CommandAllocatorPoolDX12(GPUDeviceDX12* device, D3D12_COMMAND_LIST_TYPE type)
+    : _type(type)
+    , _device(device)
+{
+}
+
+CommandAllocatorPoolDX12::~CommandAllocatorPoolDX12()
+{
+    Release();
+}
+
+ID3D12CommandAllocator* CommandAllocatorPoolDX12::RequestAllocator(uint64 completedFenceValue)
+{
+    ScopeLock lock(_locker);
+
+    ID3D12CommandAllocator* allocator = nullptr;
+
+    if (_ready.HasItems())
+    {
+        PoolPair& firstPair = _ready.First();
+
+        if (firstPair.First <= completedFenceValue)
+        {
+            allocator = firstPair.Second;
+            VALIDATE_DIRECTX_RESULT(allocator->Reset());
+            _ready.RemoveAtKeepOrder(0);
+        }
+    }
+
+    // If no allocators were ready to be reused, create a new one
+    if (allocator == nullptr)
+    {
+        VALIDATE_DIRECTX_RESULT(_device->GetDevice()->CreateCommandAllocator(_type, IID_PPV_ARGS(&allocator)));
+#if GPU_ENABLE_RESOURCE_NAMING
+        Char name[32];
+        swprintf(name, 32, L"CommandAllocator %u", _pool.Count());
+        allocator->SetName(name);
+#endif
+        _pool.Add(allocator);
+    }
+
+    return allocator;
+}
+
+void CommandAllocatorPoolDX12::DiscardAllocator(uint64 fenceValue, ID3D12CommandAllocator* allocator)
+{
+    ScopeLock lock(_locker);
+
+    // That fence value indicates we are free to reset the allocator
+    _ready.Add(PoolPair(fenceValue, allocator));
+}
+
+void CommandAllocatorPoolDX12::Release()
+{
+    for (int32 i = 0; i < _pool.Count(); i++)
+    {
+        DX_SAFE_RELEASE_CHECK(_pool[i], 0);
+    }
+
+    _pool.Clear();
+}
+
+#endif