> ## Documentation Index
> Fetch the complete documentation index at: https://devdocs.xbox.com/llms.txt
> Use this file to discover all available pages before exploring further.

# IASetIndexBuffer

> Sets the view for the index buffer.

Sets the view for the index buffer.

## Syntax

```cpp theme={null}
void IASetIndexBuffer(
    const D3D12_INDEX_BUFFER_VIEW  pView
)
```

### Parameters

*pView \[in, optional]*\
Type: const D3D12\_INDEX\_BUFFER\_VIEW \*

The view specifies the index buffer's address, size, and [DXGI\_FORMAT](https://learn.microsoft.com/en-us/windows/desktop/api/dxgiformat/ne-dxgiformat-dxgi_format), as a pointer to a [D3D12\_INDEX\_BUFFER\_VIEW](/reference/graphics/d3d12/structs/d3d12_index_buffer_view_public) structure.

### Return value

Type: void

None.

## Remarks

Only one index buffer can be bound to the graphics pipeline at any one time.

#### Examples

The [D3D12Bundles](https://learn.microsoft.com/en-us/windows/desktop/direct3d12/working-samples) sample uses **ID3D12GraphicsCommandList::IASetIndexBuffer** as follows:

```cpp theme={null}
void FrameResource::PopulateCommandList(ID3D12GraphicsCommandList* pCommandList, ID3D12PipelineState* pPso1, ID3D12PipelineState* pPso2,
UINT frameResourceIndex, UINT numIndices, D3D12_INDEX_BUFFER_VIEW* pIndexBufferViewDesc, D3D12_VERTEX_BUFFER_VIEW* pVertexBufferViewDesc,
ID3D12DescriptorHeap* pCbvSrvDescriptorHeap, UINT cbvSrvDescriptorSize, ID3D12DescriptorHeap* pSamplerDescriptorHeap, ID3D12RootSignature* pRootSignature)
{
// If the root signature matches the root signature of the caller, then
// bindings are inherited, otherwise the bind space is reset.
pCommandList->SetGraphicsRootSignature(pRootSignature);

ID3D12DescriptorHeap* ppHeaps[] = { pCbvSrvDescriptorHeap, pSamplerDescriptorHeap };
pCommandList->SetDescriptorHeaps(_countof(ppHeaps), ppHeaps);
pCommandList->IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);

pCommandList->IASetIndexBuffer(pIndexBufferViewDesc);

pCommandList->IASetVertexBuffers(0, 1, pVertexBufferViewDesc);

pCommandList->SetGraphicsRootDescriptorTable(0, pCbvSrvDescriptorHeap->GetGPUDescriptorHandleForHeapStart());
pCommandList->SetGraphicsRootDescriptorTable(1, pSamplerDescriptorHeap->GetGPUDescriptorHandleForHeapStart());

// Calculate the descriptor offset due to multiple frame resources.
// 1 SRV + how many CBVs we have currently.
UINT frameResourceDescriptorOffset = 1 + (frameResourceIndex * m_cityRowCount * m_cityColumnCount);
CD3DX12_GPU_DESCRIPTOR_HANDLE cbvSrvHandle(pCbvSrvDescriptorHeap->GetGPUDescriptorHandleForHeapStart(), frameResourceDescriptorOffset, cbvSrvDescriptorSize);

BOOL usePso1 = TRUE;
for (UINT i = 0; i < m_cityRowCount; i++)
{
for (UINT j = 0; j < m_cityColumnCount; j++)
{
// Alternate which PSO to use; the pixel shader is different on
// each just as a PSO setting demonstration.
pCommandList->SetPipelineState(usePso1 ? pPso1 : pPso2);
usePso1 = !usePso1;

// Set this city's CBV table and move to the next descriptor.
pCommandList->SetGraphicsRootDescriptorTable(2, cbvSrvHandle);
cbvSrvHandle.Offset(cbvSrvDescriptorSize);

pCommandList->DrawIndexedInstanced(numIndices, 1, 0, 0, 0);
}
}
}

```

See [Example Code in the D3D12 Reference](https://learn.microsoft.com/en-us/windows/desktop/direct3d12/notes-on-example-code).

<div class="code" />

## Requirements

**Header:** d3d12\_xs.h or d3d12\_x.h\
**Library:** d3d12\_xs.lib or d3d12\_x.lib\
**Supported Platforms**: XBOX Series consoles and XBOX One family

## See Also

[ID3D12GraphicsCommandList](/reference/graphics/d3d12_xs/interfaces/ID3D12GraphicsCommandList/id3d12graphicscommandlist_xs)


## Related topics

- [D3D12_INDEX_BUFFER_VIEW](/reference/graphics/d3d12/structs/d3d12_index_buffer_view_public.md)
- [IASetVertexBuffers](/reference/graphics/d3d12/interfaces/id3d12graphicscommandlist/methods/id3d12graphicscommandlist_iasetvertexbuffers_public.md)
- [SetComputeRootConstantBufferView](/reference/graphics/d3d12/interfaces/id3d12graphicscommandlist/methods/id3d12graphicscommandlist_setcomputerootconstantbufferview_public.md)
- [SetGraphicsRootConstantBufferView](/reference/graphics/d3d12/interfaces/id3d12graphicscommandlist/methods/id3d12graphicscommandlist_setgraphicsrootconstantbufferview_public.md)
- [SOSetTargets](/reference/graphics/d3d12/interfaces/id3d12graphicscommandlist/methods/id3d12graphicscommandlist_sosettargets_public.md)