如何实现SharpDX渲染至WPF D3DImage的相关函数及交换链创建？

一、核心函数实现 #

1. IntPtr InitializeScene() #

该函数负责初始化Direct3D设备、共享纹理（供D3DImage调用），并返回共享纹理句柄。

using SharpDX;
using SharpDX.Direct3D11;
using SharpDX.DXGI;
using System;
using System.Windows;

// 全局变量存储SharpDX核心资源
private Device _d3dDevice;
private Texture2D _sharedTexture;
private RenderTargetView _renderTargetView;
private D3DImage _d3dImage;

public IntPtr InitializeScene()
{
    // 初始化D3D设备，启用BGRA格式支持（适配WPF）
    var deviceFlags = DeviceCreationFlags.BgraSupport;
    _d3dDevice = new Device(DriverType.Hardware, deviceFlags);

    // 配置共享纹理参数：必须支持共享、BGRA格式
    var textureDesc = new Texture2DDescription
    {
        Width = (int)_d3dImage.Width,
        Height = (int)_d3dImage.Height,
        MipLevels = 1,
        ArraySize = 1,
        Format = Format.B8G8R8A8_UNorm,
        SampleDescription = new SampleDescription(1, 0),
        Usage = ResourceUsage.Default,
        BindFlags = BindFlags.RenderTarget | BindFlags.ShaderResource,
        CpuAccessFlags = CpuAccessFlags.None,
        OptionFlags = ResourceOptionFlags.Shared
    };

    // 创建共享纹理及对应的渲染目标视图
    _sharedTexture = new Texture2D(_d3dDevice, textureDesc);
    _renderTargetView = new RenderTargetView(_d3dDevice, _sharedTexture);

    // 获取共享纹理的句柄，供WPF D3DImage使用
    var sharedHandle = _sharedTexture.QueryInterface<SharedResource>().SharedHandle;
    return sharedHandle;
}

2. void RenderScene() #

执行渲染逻辑并更新D3DImage的显示内容：

public void RenderScene()
{
    if (_d3dImage == null || _renderTargetView == null) return;

    // 清空渲染目标背景
    _d3dDevice.ImmediateContext.ClearRenderTargetView(_renderTargetView, new Color4(0.2f, 0.2f, 0.2f, 1.0f));

    // 插入你的自定义渲染逻辑（如绘制模型、2D元素等）
    // ...

    // 在WPF主线程更新D3DImage，避免跨线程异常
    Application.Current.Dispatcher.Invoke(() =>
    {
        if (!_d3dImage.IsFrontBufferAvailable) return;

        _d3dImage.Lock();
        _d3dImage.SetBackBuffer(D3DResourceType.IDirect3DSurface9, _sharedTexture.NativePointer);
        _d3dImage.AddDirtyRect(new Int32Rect(0, 0, (int)_d3dImage.Width, (int)_d3dImage.Height));
        _d3dImage.Unlock();
    });
}

3. void ReleaseScene() #

释放所有SharpDX资源，防止内存泄漏：

public void ReleaseScene()
{
    // 按资源创建逆序释放
    _renderTargetView?.Dispose();
    _sharedTexture?.Dispose();
    _d3dDevice?.Dispose();
}

二、交换链创建与WPF可用指针获取 #

如果原有渲染逻辑依赖交换链，可创建离屏交换链，再将其后台缓冲区转为共享资源供WPF使用：

// 离屏交换链配置
var swapChainDesc = new SwapChainDescription
{
    BufferCount = 1,
    ModeDescription = new ModeDescription((int)_d3dImage.Width, (int)_d3dImage.Height, new Rational(60, 1), Format.B8G8R8A8_UNorm),
    IsWindowed = false, // 启用离屏模式
    OutputHandle = IntPtr.Zero, // 无需绑定窗口句柄
    SampleDescription = new SampleDescription(1, 0),
    SwapEffect = SwapEffect.Discard,
    Usage = Usage.RenderTargetOutput | Usage.Shared // 启用共享属性
};

// 创建交换链并获取后台缓冲区的共享句柄
var swapChain = new SwapChain(_d3dDevice.Factory, _d3dDevice, swapChainDesc);
var backBuffer = Texture2D.FromSwapChain<Texture2D>(swapChain, 0);
var sharedHandle = backBuffer.QueryInterface<SharedResource>().SharedHandle;

直接使用共享纹理时，无需额外创建交换链，直接通过_sharedTexture.NativePointer即可向D3DImage传递帧数据。

三、关于WPF窗口句柄的说明 #

SharpDX结合D3DImage时不需要WPF窗口的句柄。D3DImage通过共享Direct3D纹理传递渲染内容，所有渲染操作在离屏共享纹理中完成，再由WPF控件负责将纹理内容绘制到界面，无需直接绑定窗口设备上下文。

内容的提问来源于stack exchange，提问作者C.G.