CheckMultisampleQualityLevels(...) says the card does not support MSAA (which is not true for e.g. my GeForce GTX 780)?

Question

I use CheckMultisampleQualityLevels(...) to establish the MSAA support on my hardware. I do it in that order:

1. D3D11CreateDevice(...) gives me device
2. device->CheckMultisampleQualityLevels(...)
3. Pass results to DXGI_SWAP_CHAIN_DESC.SampleDesc
4. CreateSwapChain(...) with given DXGI_SWAP_CHAIN_DESC

The problem is, CheckMultisampleQualityLevels(...) always gives me 0 for pNumQualityLevels. And I'm sure that my graphic card supports some MSAA (I've tested the program on GeForce gtx 780 and others with the same result).

Did I miss something? Should I call something else before CheckMultisampleQualityLevels(...)?

The code:

Create device:

UINT createDeviceFlags = 0;
#ifdef DEBUG_DIRECTX
 createDeviceFlags |= D3D11_CREATE_DEVICE_DEBUG;
#endif

D3D_DRIVER_TYPE driverTypes[] = {
    D3D_DRIVER_TYPE_HARDWARE,
    D3D_DRIVER_TYPE_WARP,
    D3D_DRIVER_TYPE_REFERENCE,
};
std::string driverTypesNames[] = {
    "D3D_DRIVER_TYPE_HARDWARE",
    "D3D_DRIVER_TYPE_WARP",
    "D3D_DRIVER_TYPE_REFERENCE",
};
UINT numDriverTypes = ARRAYSIZE(driverTypes);

D3D_FEATURE_LEVEL featureLevels[] = {
    D3D_FEATURE_LEVEL_11_0,
    D3D_FEATURE_LEVEL_10_1,
    D3D_FEATURE_LEVEL_10_0,
};
std::string featureLevelsNames[] = {
    "D3D_FEATURE_LEVEL_11_0",
    "D3D_FEATURE_LEVEL_10_1",
    "D3D_FEATURE_LEVEL_10_0",
};
UINT numFeatureLevels = ARRAYSIZE(featureLevels);

D3D_FEATURE_LEVEL g_featureLevel = D3D_FEATURE_LEVEL_11_0;
for(UINT driverTypeIndex = 0; driverTypeIndex < numDriverTypes; driverTypeIndex++){
    driverType = driverTypes[driverTypeIndex];
    result = D3D11CreateDevice(NULL, driverType, NULL, createDeviceFlags, featureLevels, numFeatureLevels, D3D11_SDK_VERSION, &device, &g_featureLevel, &context);
    if(SUCCEEDED(result)){
        LOG(logDEBUG1, "Driver type: " << driverTypesNames[driverTypeIndex] << ".", MOD_GRAPHIC);
        break;
    }
}
ERROR_HANDLE(SUCCEEDED(result), L"Could not create device (DirectX 11).", MOD_GRAPHIC);

Check multi-sample quality levels (based on vertexwahn.de article):

sampleCountOut = 1;
maxQualityLevelOut = 0;
for(UINT sampleCount = 1; sampleCount <= D3D11_MAX_MULTISAMPLE_SAMPLE_COUNT; sampleCount++){
    UINT maxQualityLevel = 0;
    HRESULT hr = device->CheckMultisampleQualityLevels(DXGI_FORMAT_R8G8B8A8_UNORM, sampleCount, &maxQualityLevel);
    if(maxQualityLevel > 0){
        maxQualityLevel--;
    }
    ERROR_HANDLE(hr == S_OK, L"CheckMultisampleQualityLevels failed.", MOD_GRAPHIC);

    if(maxQualityLevel > 0){
        LOG(logDEBUG1, "MSAA " << sampleCount << "X supported with " << maxQualityLevel << " quality levels.", MOD_GRAPHIC);
        sampleCountOut = sampleCount;
        maxQualityLevelOut = maxQualityLevel;
    }
}

Swap chain:

DXGI_SWAP_CHAIN_DESC sd;
ZeroMemory(&sd, sizeof(sd));
sd.BufferCount = 1;
sd.BufferDesc.Width = width;
sd.BufferDesc.Height = height;
sd.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
sd.BufferDesc.RefreshRate.Numerator = 60;
sd.BufferDesc.RefreshRate.Denominator = 1;
sd.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
sd.OutputWindow = *hwnd;
sd.SampleDesc.Count = sampleCount;
sd.SampleDesc.Quality = maxQualityLevel;
sd.Windowed = false;
sd.Flags = DXGI_SWAP_CHAIN_FLAG_ALLOW_MODE_SWITCH;     // allow full-screen switchin


//based on http://stackoverflow.com/questions/27270504/directx-creating-the-swapchain
IDXGIDevice * dxgiDevice = 0;
HRESULT hr = device->QueryInterface(__uuidof(IDXGIDevice), (void **)& dxgiDevice);
ERROR_HANDLE(SUCCEEDED(hr), L"Query for IDXGIDevice failed.", MOD_GRAPHIC);

IDXGIAdapter * dxgiAdapter = 0;
hr = dxgiDevice->GetParent(__uuidof(IDXGIAdapter), (void **)& dxgiAdapter);
ERROR_HANDLE(SUCCEEDED(hr), L"Could not get IDXGIAdapter.", MOD_GRAPHIC);

IDXGIFactory * dxgiFactory = 0;
hr = dxgiAdapter->GetParent(__uuidof(IDXGIFactory), (void **)& dxgiFactory);
ERROR_HANDLE(SUCCEEDED(hr), L"Could not get IDXGIFactory.", MOD_GRAPHIC);

// This system only has DirectX 11.0 installed (let's assume it)
result = dxgiFactory->CreateSwapChain(device, &sd, &swapChain);
LOG(logDEBUG1, "This system only has DirectX 11.0 installed. CreateSwapChain(...) used.", MOD_GRAPHIC);

ERROR_HANDLE(result == S_OK, L"Could not swap chain.", MOD_GRAPHIC);

My ERROR_HANDLE(...) macro never triggers (the first parameter is true in all cases). The log says I use D3D_DRIVER_TYPE_HARDWARE for driver type.

The DirectX Debuggers says (which is some problem, but I don't think it's the reason for CheckMultisampleQualityLevels(...) to gives me wrong results):

DXGI WARNING: IDXGISwapChain::Present: Fullscreen presentation inefficiencies incurred due to application not using IDXGISwapChain::ResizeBuffers appropriately, specifying a DXGI_MODE_DESC not available in IDXGIOutput::GetDisplayModeList, or not using DXGI_SWAP_CHAIN_FLAG_ALLOW_MODE_SWITCH.DXGI_SWAP_CHAIN_DESC::BufferDesc = { 1600, 900, { 60, 1 }, R8G8B8A8_UNORM, 0, 0 }; DXGI_SWAP_CHAIN_DESC::SampleDesc = { 8, 0 }; DXGI_SWAP_CHAIN_DESC::Flags = 0x2; [ MISCELLANEOUS WARNING #98: ]

Answer 1

Your code subtracts 1 from maxQualityLevels before checking to see whether it's greater than zero. An initial value of 1 would suggest it's valid to create the target at quality level 0.

Assuming you want this to work across vendors you only really need to check for it being > 0 and then just create the surface at Quality = 0.

Quality levels > 0 are vendor specific and can mean any number of things to different GPUs. Nvidia's CSAA and AMD's EQAA are both available through non-zero quality levels, but you'd need to look at their own documentation to figure out what each quality level actually means. They're also functionally slightly different to traditional MSAA. "Quality" is a little misleading in the sense that a greater number doesn't necessarily mean greater quality, it would be more appropriate to call it "Mode"

See both:

http://www.nvidia.com/object/coverage-sampled-aa.html

and

http://developer.amd.com/wordpress/media/2012/10/EQAA%2520Modes%2520for%2520AMD%2520HD%25206900%2520Series%2520Cards.pdf