如何将附近的像素数据发送到 Direct3D 11 中的像素着色器？

Question

我一直在阅读这些教程（我只允许使用 2 个链接）：https://code.msdn.microsoft.com/Direct3D-Tutorial-Win32-829979ef

并通过 Direct3D 11 图形管道读取：https://msdn.microsoft.com/en-us/library/windows/desktop/ff476882%28v=vs.85%29.aspx

我目前有一个用 HLSL 编码的像素（又名片段）着色器，由以下代码组成：

//Pixel Shader input.
struct psInput
{
    float4 Position: SV_POSITION;
    float4 Color: COLOR;
};

//Pixel (aka. Fragment) Shader.
float4 PS(psInput input): SV_TARGET
{
    return input.Color;
}

我（想我）想做的是多重采样并访问像素着色器中每个像素的附近像素数据，以便我可以执行一种自定义抗锯齿，如 FXAA (http://developer.download.nvidia.com/assets/gamedev/files/sdk/11/FXAA_WhitePaper.pdf)。据我了解，我需要为每个渲染使用 PSSetShaderResources 将纹理传递给 HLSL，但除此之外我不知道。所以，我的问题是：

如何将附近的像素数据发送到 Direct3D 11 中的像素着色器？

除了我在教程中找到的标准“将一些 float4 传递给着色器”之外，能够做这种事情也对我理解 c++ 和 HLSL 如何相互交互非常有益。这似乎是 D3D 开发中最关键的方面，但我在网上找不到很多它的例子。

我考虑过传统的 MSAA（MultiSample Anti-Aliasing），但除了我需要使用“BitBlt”（位块传输）之外，我找不到任何关于如何在 D3D 11 中成功实现它的信息首先是模型交换链。 （请参阅 DXGI_SAMPLE_DESC1 和 DXGI_SAMPLE_DESC；只有计数为 1 和质量为 0（无 AA）会导致绘制内容。）此外，我想知道如何执行上述操作以进行一般理解，以防我需要它用于其他操作我项目的各个方面。不过，也欢迎有关如何在 D3D 11 中执行 MSAA 的答案。

请仅使用 D3D 11 和 HLSL 代码。

Answer 1

要进行像 FXAA 这样的自定义抗锯齿，您需要将场景渲染到屏幕外渲染目标：

-使用绑定标志D3D11_BIND_RENDER_TARGET 和D3D11_BIND_SHADER_RESOURCE 创建一个ID3D11Texture2D

-为第一步中创建的纹理创建ID3D11ShaderResourceView 和ID3D11RenderTargetView。

-将场景渲染到步骤2中创建的ID3D11RenderTargetView

-将后备缓冲区设置为渲染目标，并将步骤 2 中创建的ID3D11ShaderResourceView 绑定到正确的像素着色器插槽。

-Render a fullscreen triangle covering the entire screen 您将能够在像素着色器中对包含场景的纹理进行采样（使用Load() 函数）

---

当您尝试进行传统 MSAA 时，您是否记得设置 MultisampleEnable in the rasterizer state？

Answer 2

我再次回答我自己的问题，有点（从未使用过 FXAA...）。我在这里提供我的答案是为了对那些追随我脚步的人好。

原来我错过了 MSAA 的深度模具视图。您希望 SampleCount 对于禁用的 MSAA 为 1U，对于 2XMSAA 为 2U，对于 4XMSAA 为 4U，对于 8XMSAA 为 8U 等。（使用ID3D11Device::CheckMultisampleQualityLevels 来“探测”可行的 MSAA 级别...）您几乎总是希望使用质量禁用 MSAA 的级别为 0U，启用的 MSAA 级别为 1U。

以下是我的工作 MSAA 代码（您应该可以填写其余部分）。请注意，我使用了 DXGI_FORMAT_D24_UNORM_S8_UINT 和 D3D11_DSV_DIMENSION_TEXTURE2DMS，并且深度纹理和深度模板视图的 Format 值相同，SampleCount 和 SampleQuality 值相同。

祝你好运！

    unsigned int SampleCount = 1U;
    unsigned int SampleQuality = (SampleCount > 1U ? 1U : 0U);




//Create swap chain.

IDXGIFactory2* dxgiFactory2 = nullptr;

d3dResult = dxgiFactory->QueryInterface(__uuidof(IDXGIFactory2), reinterpret_cast<void**>(&dxgiFactory2));

if (dxgiFactory2)
{
    //DirectX 11.1 or later.
    d3dResult = D3DDevice->QueryInterface(__uuidof(ID3D11Device1), reinterpret_cast<void**>(&D3DDevice1));

    if (SUCCEEDED(d3dResult))
    {
        D3DDeviceContext->QueryInterface(__uuidof(ID3D11DeviceContext1), reinterpret_cast<void**>(&D3DDeviceContext1));
    }

    DXGI_SWAP_CHAIN_DESC1 swapChain;
    ZeroMemory(&swapChain, sizeof(swapChain));
    swapChain.Width = width;
    swapChain.Height = height;
    swapChain.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
    swapChain.SampleDesc.Count = SampleCount;
    swapChain.SampleDesc.Quality = SampleQuality;
    swapChain.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
    swapChain.BufferCount = 2U;

    d3dResult = dxgiFactory2->CreateSwapChainForHwnd(D3DDevice, w32Window, &swapChain, nullptr, nullptr, &SwapChain1);

    if (SUCCEEDED(d3dResult))
    {
        d3dResult = SwapChain1->QueryInterface(__uuidof(IDXGISwapChain), reinterpret_cast<void**>(&SwapChain));
    }

    dxgiFactory2->Release();
}
else
{
    //DirectX 11.0.
    DXGI_SWAP_CHAIN_DESC swapChain;
    ZeroMemory(&swapChain, sizeof(swapChain));
    swapChain.BufferCount = 2U;
    swapChain.BufferDesc.Width = width;
    swapChain.BufferDesc.Height = height;
    swapChain.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
    swapChain.BufferDesc.RefreshRate.Numerator = 60U;
    swapChain.BufferDesc.RefreshRate.Denominator = 1U;
    swapChain.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
    swapChain.OutputWindow = w32Window;
    swapChain.SampleDesc.Count = SampleCount;
    swapChain.SampleDesc.Quality = SampleQuality;
    swapChain.Windowed = true;

    d3dResult = dxgiFactory->CreateSwapChain(D3DDevice, &swapChain, &SwapChain);
}

//Disable Alt + Enter and Print Screen shortcuts.
dxgiFactory->MakeWindowAssociation(w32Window, DXGI_MWA_NO_PRINT_SCREEN | DXGI_MWA_NO_ALT_ENTER);

dxgiFactory->Release();

if (FAILED(d3dResult))
{
    return false;
}






//Create render target view.

ID3D11Texture2D* backBuffer = nullptr;
d3dResult = SwapChain->GetBuffer(0U, __uuidof(ID3D11Texture2D), reinterpret_cast<void**>(&backBuffer));

if (FAILED(d3dResult))
{
    return false;
}

d3dResult = D3DDevice->CreateRenderTargetView(backBuffer, nullptr, &RenderTargetView);

backBuffer->Release();

if (FAILED(d3dResult))
{
    return false;
}


//Create depth stencil texture.

ID3D11Texture2D* DepthStencilTexture = nullptr;

D3D11_TEXTURE2D_DESC depthTextureLayout;
ZeroMemory(&depthTextureLayout, sizeof(depthTextureLayout));
depthTextureLayout.Width = width;
depthTextureLayout.Height = height;
depthTextureLayout.MipLevels = 1U;
depthTextureLayout.ArraySize = 1U;
depthTextureLayout.Usage = D3D11_USAGE_DEFAULT;
depthTextureLayout.CPUAccessFlags = 0U;
depthTextureLayout.MiscFlags = 0U;
depthTextureLayout.Format = DXGI_FORMAT_D24_UNORM_S8_UINT;
depthTextureLayout.SampleDesc.Count = SampleCount;
depthTextureLayout.SampleDesc.Quality = SampleQuality;
depthTextureLayout.BindFlags = D3D11_BIND_DEPTH_STENCIL;
d3dResult = D3DDevice->CreateTexture2D(&depthTextureLayout, nullptr, &DepthStencilTexture);

if (FAILED(d3dResult))
{
    return false;
}


//Create depth stencil.
D3D11_DEPTH_STENCIL_DESC depthStencilLayout;
depthStencilLayout.DepthEnable = true;
depthStencilLayout.DepthWriteMask = D3D11_DEPTH_WRITE_MASK_ALL;
depthStencilLayout.DepthFunc = D3D11_COMPARISON_LESS;
depthStencilLayout.StencilEnable = true;
depthStencilLayout.StencilReadMask = 0xFF;
depthStencilLayout.StencilWriteMask = 0xFF;
depthStencilLayout.FrontFace.StencilFailOp = D3D11_STENCIL_OP_KEEP;
depthStencilLayout.FrontFace.StencilDepthFailOp = D3D11_STENCIL_OP_INCR;
depthStencilLayout.FrontFace.StencilPassOp = D3D11_STENCIL_OP_KEEP;
depthStencilLayout.FrontFace.StencilFunc = D3D11_COMPARISON_ALWAYS;
depthStencilLayout.BackFace.StencilFailOp = D3D11_STENCIL_OP_KEEP;
depthStencilLayout.BackFace.StencilDepthFailOp = D3D11_STENCIL_OP_INCR;
depthStencilLayout.BackFace.StencilPassOp = D3D11_STENCIL_OP_KEEP;
depthStencilLayout.BackFace.StencilFunc = D3D11_COMPARISON_ALWAYS;
ID3D11DepthStencilState* depthStencilState;
D3DDevice->CreateDepthStencilState(&depthStencilLayout, &depthStencilState);
D3DDeviceContext->OMSetDepthStencilState(depthStencilState, 1U);



//Create depth stencil view.

D3D11_DEPTH_STENCIL_VIEW_DESC depthStencilViewLayout;
ZeroMemory(&depthStencilViewLayout, sizeof(depthStencilViewLayout));
depthStencilViewLayout.Format = depthTextureLayout.Format;
depthStencilViewLayout.ViewDimension = D3D11_DSV_DIMENSION_TEXTURE2DMS;
depthStencilViewLayout.Texture2D.MipSlice = 0U;
d3dResult = D3DDevice->CreateDepthStencilView(DepthStencilTexture, &depthStencilViewLayout, &DepthStencilView);

DepthStencilTexture->Release();

if (FAILED(d3dResult))
{
    return false;
}


//Set output-merger render targets.
D3DDeviceContext->OMSetRenderTargets(1U, &RenderTargetView, DepthStencilView);