D3D12：无法创建尺寸超25000的一维缓冲区/纹理？求解决办法

我理论上的需求很简单，但实践中无法实现：希望在光线追踪Shader中对动态大小的float数组进行读写操作，我认为应将其声明为UAV。我尝试将其声明为RWTexture1D<float>和RWBuffer<float>，但指定约100k的尺寸时均报错，提示维度过大，其中RWBuffer<float>似乎限制为25k，RWTexture1D<float>限制为16384。

编辑1：相关代码与报错 #

以下是创建UAV的代码：

D3D12_UNORDERED_ACCESS_VIEW_DESC unordered_access_view_desc{};
unordered_access_view_desc.Buffer.NumElements = 100000;
unordered_access_view_desc.Format = DXGI_FORMAT_R32_FLOAT;
unordered_access_view_desc.ViewDimension = D3D12_UAV_DIMENSION_BUFFER;

d3d.device->CreateUnorderedAccessView(resource, nullptr, &unordered_access_view_desc, handle);

报错信息：

The Dimensions of the View are invalid due to at least one of the following conditions. Assuming this Format (0x29, R32_FLOAT), FirstElement (value = 0) must be between 0 and the maximum offset of the Buffer, 24999, inclusively.

我无法理解：若改用DXGI_FORMAT_R32G32B32A32_FLOAT格式，设置Buffer.NumElements = 25000，内存占用量是相同的。但即便用这种取巧方式，真的无法创建尺寸>25000的一维数组吗？就连简单的512x512二维纹理都有262144个值，难道我必须创建二维纹理并重新索引吗？

编辑2：CreateBuffer与CreateCommittedResource代码 #

以下是创建Buffer的相关代码：

D3D12_HEAP_PROPERTIES heapDesc = {};
heapDesc.Type = D3D12_HEAP_TYPE_DEFAULT;
heapDesc.CreationNodeMask = 1;
heapDesc.VisibleNodeMask = 1;

D3D12_RESOURCE_DESC resourceDesc = {};
resourceDesc.Dimension = D3D12_RESOURCE_DIMENSION_BUFFER;
resourceDesc.Height = 1;
resourceDesc.DepthOrArraySize = 1;
resourceDesc.MipLevels = 1;
resourceDesc.Format = DXGI_FORMAT_UNKNOWN;
resourceDesc.SampleDesc.Count = 1;
resourceDesc.SampleDesc.Quality = 0;
resourceDesc.Layout = D3D12_TEXTURE_LAYOUT_ROW_MAJOR;
resourceDesc.Width = /* ... */;
resourceDesc.Flags = D3D12_RESOURCE_FLAG_ALLOW_UNORDERED_ACCESS;

device->CreateCommittedResource(&heapDesc, D3D12_HEAP_FLAG_NONE, &resourceDesc, D3D12_RESOURCE_STATE_UNORDERED_ACCESS, nullptr, IID_PPV_ARGS(&myresource));

以及另一处CreateCommittedResource的代码：

D3D12_HEAP_PROPERTIES const DefaultHeapProperties =
{
    D3D12_HEAP_TYPE_DEFAULT,
    D3D12_CPU_PAGE_PROPERTY_UNKNOWN,
    D3D12_MEMORY_POOL_UNKNOWN,
    0, 0
};

D3D12_RESOURCE_DESC resource_desc{};
resource_desc.DepthOrArraySize = 1;
resource_desc.Dimension = D3D12_RESOURCE_DIMENSION_BUFFER;
//resource_desc.Dimension = D3D12_RESOURCE_DIMENSION_TEXTURE2D;
resource_desc.Format = DXGI_FORMAT_UNKNOWN;
//resource_desc.Format = DXGI_FORMAT_R32_FLOAT;
resource_desc.Flags = D3D12_RESOURCE_FLAG_ALLOW_UNORDERED_ACCESS;
resource_desc.Width = static_cast<UINT64>(resources.raytracingData.bootstrap_sample_count);
resource_desc.Height = 1;
//resource_desc.Width = /* ... */;
resource_desc.Layout = D3D12_TEXTURE_LAYOUT_ROW_MAJOR;
resource_desc.MipLevels = 1;
resource_desc.SampleDesc.Count = 1;

device->CreateCommittedResource(&DefaultHeapProperties, D3D12_HEAP_FLAG_NONE, &resource_desc, D3D12_RESOURCE_STATE_UNORDERED_ACCESS, nullptr, IID_PPV_ARGS(&myresource));

内容的提问来源于stack exchange，提问作者0xbadf00d