52 lines
1.3 KiB
C
52 lines
1.3 KiB
C
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//--------------------------------------------------------------------------------------
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// File: DemandCreate.h
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//
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// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
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// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
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// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
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// PARTICULAR PURPOSE.
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//
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// Copyright (c) Microsoft Corporation. All rights reserved.
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//
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// http://go.microsoft.com/fwlink/?LinkId=248929
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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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static 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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MemoryBarrier();
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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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MemoryBarrier();
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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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