Direct2D中的多线程 [英] Multithreading in Direct2D

问题描述

我想创建一个简单的D2D游戏引擎（它必须能够在窗口中显示和移动图像，至少），一切顺利，直到我决定切换到多线程版本的那一刻。我阅读了此 MSDN文章，并且建议从多个线程使用一个多线程工厂。但此文章声称它会更有效的几个单线程工厂（虽然本文描述服务器端渲染场景，原则是一样的我的情况，我错了吗？）。当我试图使用单线程单工厂方法，所有的图像显示和移动，但有可怕的闪烁。在我的WM_PAINT处理程序中，我试图做这样的事情：

I'm trying to create a simple D2D game engine (it must be able to display and move images in a window, at least), and everything went right until the moment when I decided to switch to the multithreaded version. I read this MSDN article, and it recommends using one multithreaded factory from several threads. But this article claims it would be more effective to have several single-threaded factories (though the article describes server-side rendering scenario, the principle is the same for my case, am I wrong?). When I tried to use one-thread-one-factory approach, all the images are displayed and moved, but there's terrible flickering. In my WM_PAINT handler I'm trying to do something like this:

for (CSingleThreadEngine *pElSingleThreadEngine : m_SingleThreadEngines) //each CSingleThreadEngine instance has its own D2D factory and an image collection
    pElSingleThreadEngine->Draw();

和pElSingleThreadEngine-> Draw（）绘制如下：

and pElSingleThreadEngine->Draw() does drawing like this:

m_pRenderTarget->BeginDraw();
m_pRenderTarget->SetTransform(D2D1::Matrix3x2F::Identity());
m_pRenderTarget->Clear(D2D1::ColorF(D2D1::ColorF::White));
for (CGameImage *pImage : m_GameImages)
{
    if (FAILED(pImage->Draw()))
        throw runtime_error("An object cannot be drawn");
}
m_pRenderTarget->EndDraw();

我认为错误的事情是，只有一个窗口有几个ID2D1HwndRenderTarget实例，线程在一个单独的窗口，它的工作原理很好。但是我想在一个窗口只绘制，我不能避免使用多个ID2D1HwndRenderTarget实例为此目的。所以我的问题是：

I think the wrong thing here is having several ID2D1HwndRenderTarget instances for just one window because if I make drawing each thread in a separate window, it works just fine. But I want to draw in one window only, and I can't avoid using multiple ID2D1HwndRenderTarget instances for this purpose. So my questions are:

1. 创建多线程Direct2D应用程序的最佳做法是什么？


2. 如果我使用的方法是正确的，我做错了什么，如何解决？

任何帮助非常感谢。

推荐答案

我看不到一个原因，为单个窗口使用几个HWND渲染目标。你尝试为每个线程创建offscrean位图，并将它们绘制到单个hwnd渲染目标？

I can't see a reason why you use several HWND render targets for a single window. Have you tried creating offscrean bitmaps for each thread and draw those to a single hwnd render target instead?

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