An example of CPU side descriptor heap.

SetRenderTarget.cpp

ComPtr<ID3D12DescriptorHeap> rtvHeap, dsvHeap;
ID3D12GraphicsCommandList* commandList;
ID3D12Device* device;

void CreateHeaps()
{
	D3D12_DESCRIPTOR_HEAP_DESC rtvDesc = { D3D12_DESCRIPTOR_HEAP_TYPE_RTV, 1 };
	device->CreateDescriptorHeap(&rtvDesc, IID_PPV_ARGS(&rtvHeap));
	D3D12_DESCRIPTOR_HEAP_DESC dsvDesc = { D3D12_DESCRIPTOR_HEAP_TYPE_DSV, 1 };
	device->CreateDescriptorHeap(&dsvDesc, IID_PPV_ARGS(&rtvHeap));
}

void SetRenderTarget(ComPtr<ID3D12Resource> color, ComPtr<ID3D12Resource> depthStencil)
{
	D3D12_CPU_DESCRIPTOR_HANDLE dsvHandle = dsvHeap->GetCPUDescriptorHandleForHeapStart();
	D3D12_CPU_DESCRIPTOR_HANDLE rtvHandle = rtvHeap->GetCPUDescriptorHandleForHeapStart();
	
	// this overwrites descriptor heaps in every single call of SetRenderTarget, but it's no problem.
	// because, the descriptor heap for RTV or DSV is in CPU side, not in VRAM like SRV and CBV.
	// refer https://youtu.be/Uwhhdktaofg for more detail.
	device->CreateRenderTargetView(color.Get(), nullptr, rtvHandle);
	device->CreateDepthStencilView(depthStencil.Get(), nullptr, dsvHandle);

	commandList->ClearRenderTargetView(rtvHandle, clearColor, 0, nullptr);
	commandList->ClearDepthStencilView(dsvHandle, D3D12_CLEAR_FLAG_DEPTH | D3D12_CLEAR_FLAG_STENCIL, 1.0f, 0, 0, nullptr);
	commandList->OMSetRenderTargets(1, &rtvHandle, FALSE, &dsvHandle);
}