ID3D12Device::CreateQueryHeap method (d3d12.h)
Creates a query heap. A query heap contains an array of queries.
Syntax
HRESULT CreateQueryHeap(
[in] const D3D12_QUERY_HEAP_DESC *pDesc,
REFIID riid,
[out, optional] void **ppvHeap
);
Parameters
[in] pDesc
Type: const D3D12_QUERY_HEAP_DESC*
Specifies the query heap in a D3D12_QUERY_HEAP_DESC structure.
riid
Type: REFIID
Specifies a REFIID that uniquely identifies the heap.
[out, optional] ppvHeap
Type: void**
Specifies a pointer to the heap, that will be returned on successful completion of the method. ppvHeap can be NULL, to enable capability testing. When ppvHeap is NULL, no object will be created and S_FALSE will be returned when pDesc is valid.
Return value
Type: HRESULT
This method returns one of the Direct3D 12 Return Codes.
Remarks
Refer to Queries for more information.
Examples
The D3D12PredicationQueries sample uses ID3D12Device::CreateQueryHeap as follows:
Create a query heap and a query result buffer.
// Pipeline objects.
D3D12_VIEWPORT m_viewport;
D3D12_RECT m_scissorRect;
ComPtr<IDXGISwapChain3> m_swapChain;
ComPtr<ID3D12Device> m_device;
ComPtr<ID3D12Resource> m_renderTargets[FrameCount];
ComPtr<ID3D12CommandAllocator> m_commandAllocators[FrameCount];
ComPtr<ID3D12CommandQueue> m_commandQueue;
ComPtr<ID3D12RootSignature> m_rootSignature;
ComPtr<ID3D12DescriptorHeap> m_rtvHeap;
ComPtr<ID3D12DescriptorHeap> m_cbvHeap;
ComPtr<ID3D12DescriptorHeap> m_dsvHeap;
ComPtr<ID3D12QueryHeap> m_queryHeap;
UINT m_rtvDescriptorSize;
UINT m_cbvSrvDescriptorSize;
UINT m_frameIndex;
// Synchronization objects.
ComPtr<ID3D12Fence> m_fence;
UINT64 m_fenceValues[FrameCount];
HANDLE m_fenceEvent;
// Asset objects.
ComPtr<ID3D12PipelineState> m_pipelineState;
ComPtr<ID3D12PipelineState> m_queryState;
ComPtr<ID3D12GraphicsCommandList> m_commandList;
ComPtr<ID3D12Resource> m_vertexBuffer;
ComPtr<ID3D12Resource> m_constantBuffer;
ComPtr<ID3D12Resource> m_depthStencil;
ComPtr<ID3D12Resource> m_queryResult;
D3D12_VERTEX_BUFFER_VIEW m_vertexBufferView;
// 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)));
Refer to the Example Code in the D3D12 Reference.
Requirements
| Requirement | Value |
|---|---|
| Target Platform | Windows |
| Header | d3d12.h |
| Library | D3D12.lib |
| DLL | D3D12.dll |