Hi, I'm trying to learn DirectX12 using the MSDN samples and I am trying to create a shader that has a constant buffer and a shader resource. I create my root signature like this (the cbuffer and srv are bouund to slots b0 and t0 in the shader):

CD3DX12_DESCRIPTOR_RANGE1 ranges[2];
        ranges[0].Init(D3D12_DESCRIPTOR_RANGE_TYPE_SRV, 1, 0, 0, D3D12_DESCRIPTOR_RANGE_FLAG_DATA_STATIC);
        ranges[1].Init(D3D12_DESCRIPTOR_RANGE_TYPE_CBV, 1, 0, 0, D3D12_DESCRIPTOR_RANGE_FLAG_DATA_STATIC);

        CD3DX12_ROOT_PARAMETER1 rootParameters[2];
        rootParameters[0].InitAsDescriptorTable(1, &ranges[0], D3D12_SHADER_VISIBILITY_PIXEL);
        rootParameters[1].InitAsDescriptorTable(1, &ranges[1], D3D12_SHADER_VISIBILITY_VERTEX);

        D3D12_STATIC_SAMPLER_DESC sampler = {};
        sampler.Filter = D3D12_FILTER_MIN_MAG_MIP_POINT;
        sampler.AddressU = D3D12_TEXTURE_ADDRESS_MODE_BORDER;
        sampler.AddressV = D3D12_TEXTURE_ADDRESS_MODE_BORDER;
        sampler.AddressW = D3D12_TEXTURE_ADDRESS_MODE_BORDER;
        sampler.MipLODBias = 0;
        sampler.MaxAnisotropy = 0;
        sampler.ComparisonFunc = D3D12_COMPARISON_FUNC_NEVER;
        sampler.BorderColor = D3D12_STATIC_BORDER_COLOR_TRANSPARENT_BLACK;
        sampler.MinLOD = 0.0f;
        sampler.MaxLOD = D3D12_FLOAT32_MAX;
        sampler.ShaderRegister = 0;
        sampler.RegisterSpace = 0;
        sampler.ShaderVisibility = D3D12_SHADER_VISIBILITY_PIXEL;

        CD3DX12_VERSIONED_ROOT_SIGNATURE_DESC rootSignatureDesc;
        rootSignatureDesc.Init_1_1(_countof(rootParameters), rootParameters, 1, &sampler, D3D12_ROOT_SIGNATURE_FLAG_ALLOW_INPUT_ASSEMBLER_INPUT_LAYOUT);

And in my render loop I do this:

 m_commandList->SetGraphicsRootSignature(m_rootSignature.Get());

    auto heap = m_srvHeap.Get();
    m_commandList->SetDescriptorHeaps(1, &heap);
    m_commandList->SetGraphicsRootDescriptorTable(0, m_srvHeap->GetGPUDescriptorHandleForHeapStart());

    heap = m_cbvHeap.Get();
    m_commandList->SetDescriptorHeaps(1, &heap);
    m_commandList->SetGraphicsRootDescriptorTable(1, m_cbvHeap->GetGPUDescriptorHandleForHeapStart());
    
     m_commandList->ResourceBarrier(1, &CD3DX12_RESOURCE_BARRIER::Transition(m_renderTargets[m_frameIndex].Get(), D3D12_RESOURCE_STATE_PRESENT, D3D12_RESOURCE_STATE_RENDER_TARGET));

    CD3DX12_CPU_DESCRIPTOR_HANDLE rtvHandle(m_rtvHeap->GetCPUDescriptorHandleForHeapStart(), m_frameIndex, m_rtvDescriptorSize);
    m_commandList->OMSetRenderTargets(1, &rtvHandle, FALSE, nullptr);

    // Record commands.
    const float clearColor[] = { 0.2f, 0.0f, 0.0f, 1.0f };
    m_commandList->ClearRenderTargetView(rtvHandle, clearColor, 0, nullptr);
    m_commandList->IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
    m_commandList->IASetVertexBuffers(0, 1, &m_vertexBufferView);
    m_commandList->DrawInstanced(3, 1, 0, 0);

    // Indicate that the back buffer will now be used to present.
    m_commandList->ResourceBarrier(1, &CD3DX12_RESOURCE_BARRIER::Transition(m_renderTargets[m_frameIndex].Get(), D3D12_RESOURCE_STATE_RENDER_TARGET, D3D12_RESOURCE_STATE_PRESENT));

    ThrowIfFailed(m_commandList->Close());

My cbuffer works fine because my triangle moves across the screen like in the MSDN sample, however my texture no longer works, the triangle appears black. These are the errors that I get from the debug layer, they don't seem related to my issue, although they did not appear when my root signature only had an SRV:

D3D12 WARNING: ID3D12CommandList::ClearRenderTargetView: The application did not pass any clear value to resource creation. The clear operation is typically slower as a result; but will still clear to the desired value. [ EXECUTION WARNING #820: CLEARRENDERTARGETVIEW_MISMATCHINGCLEARVALUE]

D3D12 WARNING: ID3D12CommandList::ClearRenderTargetView: The application did not pass any clear value to resource creation. The clear operation is typically slower as a result; but will still clear to the desired value. [ EXECUTION WARNING #820: CLEARRENDERTARGETVIEW_MISMATCHINGCLEARVALUE]

D3D12 ERROR: ID3D12CommandQueue::ExecuteCommandLists: Using ResourceBarrier on Command List (0x00000191041D2E90:'Unnamed ID3D12GraphicsCommandList Object'): Before state (0x4: D3D12_RESOURCE_STATE_RENDER_TARGET) of resource (0x000001917F80FAC0:'Unnamed ID3D12Resource Object') (subresource: 0) specified by transition barrier does not match with the state (0x0: D3D12_RESOURCE_STATE_[COMMON|PRESENT]) specified in the previous call to ResourceBarrier [ RESOURCE_MANIPULATION ERROR #527: RESOURCE_BARRIER_BEFORE_AFTER_MISMATCH]

How can I correctly configure the root signature to accomodate a cbuffer and shader resource view? Thanks

You can only set one heap so, this line is incorrect and not required.

heap = m_cbvHeap.Get(); 
m_commandList->SetDescriptorHeaps(1, &heap); 
m_commandList->SetGraphicsRootDescriptorTable(1, m_cbvHeap->GetGPUDescriptorHandleForHeapStart());

instead, you need to make only one heap that contains both srv and cbv, and then pass the offseted handle to command list's set function …

which means OneSRVHeap = OneSRV + oneCBV

@enzio599 thanks for your response, I have tried to create one heap and offset the handle like you said, but I am unsure by which amount to offset the handle? This is how I currently do it:

 D3D12_DESCRIPTOR_HEAP_DESC srvHeapDesc = {};
        srvHeapDesc.NumDescriptors = 2;
        srvHeapDesc.Type = D3D12_DESCRIPTOR_HEAP_TYPE_CBV_SRV_UAV;
        srvHeapDesc.Flags = D3D12_DESCRIPTOR_HEAP_FLAG_SHADER_VISIBLE;
        ThrowIfFailed(m_device->CreateDescriptorHeap(&srvHeapDesc, IID_PPV_ARGS(&m_srvHeap)));

And this is how I set my srv and buffer (I omitted some code which I think is not relevant)

CD3DX12_DESCRIPTOR_RANGE1 ranges[2];
ranges[0].Init(D3D12_DESCRIPTOR_RANGE_TYPE_SRV, 1, 0, 0, D3D12_DESCRIPTOR_RANGE_FLAG_DATA_STATIC);
ranges[1].Init(D3D12_DESCRIPTOR_RANGE_TYPE_CBV, 1, 0, 0, D3D12_DESCRIPTOR_RANGE_FLAG_DATA_STATIC);

CD3DX12_ROOT_PARAMETER1 rootParameters[2];
rootParameters[0].InitAsDescriptorTable(1, &ranges[0], D3D12_SHADER_VISIBILITY_PIXEL);
rootParameters[1].InitAsDescriptorTable(1, &ranges[1], D3D12_SHADER_VISIBILITY_VERTEX);
        
CD3DX12_CPU_DESCRIPTOR_HANDLE hDescriptor(m_srvHeap->GetCPUDescriptorHandleForHeapStart());
m_device->CreateShaderResourceView(m_texture.Get(), &srvDesc, hDescriptor);

const UINT constantBufferSize = sizeof(PerFrameCB);   
ThrowIfFailed(m_device->CreateCommittedResource(
&CD3DX12_HEAP_PROPERTIES(D3D12_HEAP_TYPE_UPLOAD),
 D3D12_HEAP_FLAG_NONE,
 &CD3DX12_RESOURCE_DESC::Buffer(constantBufferSize), D3D12_RESOURCE_STATE_GENERIC_READ,
 nullptr,
 IID_PPV_ARGS(&m_constantBuffer)));


D3D12_CONSTANT_BUFFER_VIEW_DESC cbvDesc = {};
cbvDesc.BufferLocation = m_constantBuffer->GetGPUVirtualAddress();
cbvDesc.SizeInBytes = constantBufferSize;

hDescriptor.ptr += GetRequiredIntermediateSize(m_texture.Get(), 0, 1);
m_device->CreateConstantBufferView(&cbvDesc, hDescriptor);


CD3DX12_RANGE readRange(0, 0);       
ThrowIfFailed(m_constantBuffer->Map(0, &readRange, reinterpret_cast<void**>(&m_pCbvDataBegin)));
memcpy(m_pCbvDataBegin, &m_constantBufferData, sizeof(m_constantBufferData));

As you can see I tried to offset the handle by the size of the texture, but I have also tried to use the size of the constant buffer, and both of them give this error:

D3D12 ERROR: ID3D12Device::CreateConstantBufferView: Specified CPU descriptor handle ptr=0x00000137B2C4BDDF does not refer to a location in a descriptor heap. [ EXECUTION ERROR #646: INVALID_DESCRIPTOR_HANDLE]

What is the correct offset to use in this case? Thanks

@mjp thanks for your response, I managed to create the buffer using GetDescriptorHandleIncrementSize also I forgot to set the descriptor table that contained the CBV later on when populating the command list