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> Use this file to discover all available pages before exploring further.

# GetDescriptorHandleIncrementSize

> 获取给定类型描述符堆的句柄增量大小。此值通常用于将描述符数组的句柄按此值递增。

获取给定类型描述符堆的句柄增量大小。此值通常用于将描述符数组中的句柄按正确的量递增。

## 语法

```cpp theme={null}
UINT GetDescriptorHandleIncrementSize(
    D3D12_DESCRIPTOR_HEAP_TYPE DescriptorHeapType
)
```

### 参数

*DescriptorHeapType \[in]*\
类型：D3D12\_DESCRIPTOR\_HEAP\_TYPE

[D3D12\_DESCRIPTOR\_HEAP\_TYPE](/reference/graphics/d3d12/enums/d3d12_descriptor_heap_type_public) 类型的值，用于指定要获取句柄增量大小的描述符堆类型。

### 返回值

类型：UINT

返回给定类型描述符堆的句柄增量大小，包括任何必要的填充。

## 备注

此方法返回的描述符大小用作辅助结构 [CD3DX12\_CPU\_DESCRIPTOR\_HANDLE](https://learn.microsoft.com/en-us/windows/desktop/direct3d12/cd3dx12-cpu-descriptor-handle) 和 [CD3DX12\_GPU\_DESCRIPTOR\_HANDLE](https://learn.microsoft.com/en-us/windows/desktop/direct3d12/cd3dx12-gpu-descriptor-handle) 的一个输入。

#### 示例

[D3D12PredicationQueries](https://learn.microsoft.com/en-us/windows/desktop/direct3d12/working-samples) 示例按以下方式使用 **ID3D12Device::GetDescriptorHandleIncrementSize**：

为资源创建描述符堆。<code>m\_rtvDescriptorSize</code> 变量存储渲染目标视图描述符句柄增量大小，并在代码的 **创建帧资源** 部分中使用。

```cpp theme={null}
// Create descriptor heaps.
{
// Describe and create a render target view (RTV) descriptor heap.
D3D12_DESCRIPTOR_HEAP_DESC rtvHeapDesc = {};
rtvHeapDesc.NumDescriptors = FrameCount;
rtvHeapDesc.Type = D3D12_DESCRIPTOR_HEAP_TYPE_RTV;
rtvHeapDesc.Flags = D3D12_DESCRIPTOR_HEAP_FLAG_NONE;
ThrowIfFailed(m_device->CreateDescriptorHeap(&rtvHeapDesc, IID_PPV_ARGS(&m_rtvHeap)));

// Describe and create a depth stencil view (DSV) descriptor heap.
D3D12_DESCRIPTOR_HEAP_DESC dsvHeapDesc = {};
dsvHeapDesc.NumDescriptors = 1;
dsvHeapDesc.Type = D3D12_DESCRIPTOR_HEAP_TYPE_DSV;
dsvHeapDesc.Flags = D3D12_DESCRIPTOR_HEAP_FLAG_NONE;
ThrowIfFailed(m_device->CreateDescriptorHeap(&dsvHeapDesc, IID_PPV_ARGS(&m_dsvHeap)));

// Describe and create a constant buffer view (CBV) descriptor heap.
D3D12_DESCRIPTOR_HEAP_DESC cbvHeapDesc = {};
cbvHeapDesc.NumDescriptors = CbvCountPerFrame * FrameCount;
cbvHeapDesc.Type = D3D12_DESCRIPTOR_HEAP_TYPE_CBV_SRV_UAV;
cbvHeapDesc.Flags = D3D12_DESCRIPTOR_HEAP_FLAG_SHADER_VISIBLE;
ThrowIfFailed(m_device->CreateDescriptorHeap(&cbvHeapDesc, IID_PPV_ARGS(&m_cbvHeap)));

// Describe and create a heap for occlusion queries.
D3D12_QUERY_HEAP_DESC queryHeapDesc = {};
queryHeapDesc.Count = 1;
queryHeapDesc.Type = D3D12_QUERY_HEAP_TYPE_OCCLUSION;
ThrowIfFailed(m_device->CreateQueryHeap(&queryHeapDesc, IID_PPV_ARGS(&m_queryHeap)));

m_rtvDescriptorSize = m_device->GetDescriptorHandleIncrementSize(D3D12_DESCRIPTOR_HEAP_TYPE_RTV);
m_cbvSrvDescriptorSize = m_device->GetDescriptorHandleIncrementSize(D3D12_DESCRIPTOR_HEAP_TYPE_CBV_SRV_UAV);
}

// Create frame resources.
{
CD3DX12_CPU_DESCRIPTOR_HANDLE rtvHandle(m_rtvHeap->GetCPUDescriptorHandleForHeapStart());

// Create a RTV and a command allocator for each frame.
for (UINT n = 0; n < FrameCount; n++)
{
ThrowIfFailed(m_swapChain->GetBuffer(n, IID_PPV_ARGS(&m_renderTargets[n])));
m_device->CreateRenderTargetView(m_renderTargets[n].Get(), nullptr, rtvHandle);
rtvHandle.Offset(1, m_rtvDescriptorSize);

ThrowIfFailed(m_device->CreateCommandAllocator(D3D12_COMMAND_LIST_TYPE_DIRECT, IID_PPV_ARGS(&m_commandAllocators[n])));
}
}

```

请参阅 [D3D12 参考中的示例代码](https://learn.microsoft.com/en-us/windows/desktop/direct3d12/notes-on-example-code)。

<div class="code" />

## 要求

**头文件：** d3d12\_xs.h 或 d3d12\_x.h\
**库:** d3d12\_xs.lib 或 d3d12\_x.lib\
**支持的平台**：XBOX Series 主机和 XBOX One 系列

## 另请参阅

[ID3D12Device](/reference/graphics/d3d12_x/interfaces/id3d12device/id3d12device)


## Related topics

- [D3D12_CPU_DESCRIPTOR_HANDLE](/zh-CN/reference/graphics/d3d12/structs/d3d12_cpu_descriptor_handle_public.md)
- [D3D12_GPU_DESCRIPTOR_HANDLE](/zh-CN/reference/graphics/d3d12/structs/d3d12_gpu_descriptor_handle_public.md)
- [D3D12_DESCRIPTOR_HEAP_TYPE](/zh-CN/reference/graphics/d3d12/enums/d3d12_descriptor_heap_type_public.md)
- [GetCPUDescriptorHandleForHeapStart](/zh-CN/reference/graphics/d3d12/interfaces/id3d12descriptorheap/methods/id3d12descriptorheap_getcpudescriptorhandleforheapstart_public.md)
- [GetGPUDescriptorHandleForHeapStart](/zh-CN/reference/graphics/d3d12/interfaces/id3d12descriptorheap/methods/id3d12descriptorheap_getgpudescriptorhandleforheapstart_public.md)