зеркало из https://github.com/microsoft/DirectXTK.git
59 строки
1.4 KiB
C++
59 строки
1.4 KiB
C++
//--------------------------------------------------------------------------------------
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// File: DemandCreate.h
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//
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// Copyright (c) Microsoft Corporation. All rights reserved.
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// Licensed under the MIT License.
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//
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// http://go.microsoft.com/fwlink/?LinkId=248929
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// http://go.microsoft.com/fwlink/?LinkID=615561
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//--------------------------------------------------------------------------------------
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#pragma once
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#include "PlatformHelpers.h"
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namespace DirectX
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{
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// Helper for lazily creating a D3D resource.
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template<typename T, typename TCreateFunc>
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inline T* DemandCreate(Microsoft::WRL::ComPtr<T>& comPtr, std::mutex& mutex, TCreateFunc createFunc)
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{
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T* result = comPtr.Get();
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// Double-checked lock pattern.
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#ifdef _MSC_VER
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MemoryBarrier();
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#elif defined(__GNUC__)
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__sync_synchronize();
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#else
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#error Unknown memory barrier syntax
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#endif
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if (!result)
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{
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std::lock_guard<std::mutex> lock(mutex);
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result = comPtr.Get();
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if (!result)
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{
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// Create the new object.
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ThrowIfFailed(
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createFunc(&result)
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);
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#ifdef _MSC_VER
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MemoryBarrier();
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#elif defined(__GNUC__)
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__sync_synchronize();
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#endif
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comPtr.Attach(result);
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}
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}
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return result;
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}
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}
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