我在使用 DirectX API 检测某些显卡时遇到问题。我编写的代码如下所示：
#define _WIN32_DCOM
#include <iostream>
#include <Windows.h>
#include <d3d11.h>
#include <Dxgi1_6.h>
#include <atlbase.h>
#include <string>
#include <vector>
#include <comdef.h>
#include <Wbemidl.h>
struct AdapterInfo
{
std::wstring description;
size_t vRam;
D3D_FEATURE_LEVEL maxFeatureLevel;
};
void getGPUDescriptionVideoRam(IUnknown* pDevice, AdapterInfo & adapterInfo)
{
CComPtr<IDXGIDevice> pDXGIDevice;
pDevice->QueryInterface(__uuidof(IDXGIDevice), (void**)&pDXGIDevice);
if (pDXGIDevice)
{
CComPtr<IDXGIAdapter> pDXGIAdapter;
pDXGIDevice->GetAdapter(&pDXGIAdapter);
if (pDXGIAdapter != nullptr)
{
DXGI_ADAPTER_DESC adapterDesc;
pDXGIAdapter->GetDesc(&adapterDesc);
adapterInfo.description = std::wstring(adapterDesc.Description);
adapterInfo.vRam = adapterDesc.DedicatedVideoMemory;
}
}
}
std::vector<AdapterInfo> GetDescriptionVRamDirectx()
{
std::vector<AdapterInfo> result;
D3D_FEATURE_LEVEL featureLevels[10] = { D3D_FEATURE_LEVEL_12_1,
D3D_FEATURE_LEVEL_12_0,
D3D_FEATURE_LEVEL_11_1,
D3D_FEATURE_LEVEL_11_0,
D3D_FEATURE_LEVEL_10_1,
D3D_FEATURE_LEVEL_10_0,
D3D_FEATURE_LEVEL_9_3,
D3D_FEATURE_LEVEL_9_2,
D3D_FEATURE_LEVEL_9_1,
D3D_FEATURE_LEVEL_1_0_CORE
};
CComPtr<IDXGIAdapter> higher_performance_adapter;
CComPtr<IDXGIFactory> pFactory;
HRESULT createDXGIFactoryResult = CreateDXGIFactory(__uuidof(IDXGIFactory), (void**)(&pFactory));
if (createDXGIFactoryResult != S_OK)
{
printf("Failed to create DXGI factory!\n");
return result;
}
printf("Trying to enumerate graphics adapters...\n");
int i = 0;
while (pFactory->EnumAdapters(i, &higher_performance_adapter) == S_OK)
/*
while (pFactory->EnumAdapterByGpuPreference(i,
DXGI_GPU_PREFERENCE_UNSPECIFIED,
__uuidof(IDXGIAdapter),
(void**)&higher_performance_adapter) == S_OK)
*/
{
i++;
CComPtr<ID3D11Device> device = nullptr;
D3D_FEATURE_LEVEL receivedFeatureLevel;
CComPtr<ID3D11DeviceContext> context = nullptr;
const HRESULT err = D3D11CreateDevice(
higher_performance_adapter,
D3D_DRIVER_TYPE_UNKNOWN,
nullptr,
0, // D3D11_CREATE_DEVICE_DEBUG
featureLevels,
1,
D3D11_SDK_VERSION,
&device,
&receivedFeatureLevel,
&context);
if (err != S_OK)
{
higher_performance_adapter = nullptr;
continue;
}
AdapterInfo info;
getGPUDescriptionVideoRam(device, info);
info.maxFeatureLevel = receivedFeatureLevel;
result.push_back(info);
higher_performance_adapter = CComPtr<IDXGIAdapter>();
}
return result;
}
void displayWMIAdapters()
{
HRESULT hres;
// Step 1: --------------------------------------------------
// Initialize COM. ------------------------------------------
hres = CoInitializeEx(0, COINIT_MULTITHREADED);
if (FAILED(hres))
{
std::cout << "Failed to initialize COM library. Error code = 0x"
<< std::hex << hres << std::endl;
return; // Program has failed.
}
// Step 2: --------------------------------------------------
// Set general COM security levels --------------------------
hres = CoInitializeSecurity(
NULL,
-1, // COM authentication
NULL, // Authentication services
NULL, // Reserved
RPC_C_AUTHN_LEVEL_DEFAULT, // Default authentication
RPC_C_IMP_LEVEL_IMPERSONATE, // Default Impersonation
NULL, // Authentication info
EOAC_NONE, // Additional capabilities
NULL // Reserved
);
if (FAILED(hres))
{
std::cout << "Failed to initialize security. Error code = 0x"
<< std::hex << hres << std::endl;
CoUninitialize();
return; // Program has failed.
}
// Step 3: ---------------------------------------------------
// Obtain the initial locator to WMI -------------------------
IWbemLocator* pLoc = NULL;
hres = CoCreateInstance(
CLSID_WbemLocator,
0,
CLSCTX_INPROC_SERVER,
IID_IWbemLocator, (LPVOID*)&pLoc);
if (FAILED(hres))
{
std::cout << "Failed to create IWbemLocator object."
<< " Err code = 0x"
<< std::hex << hres << std::endl;
CoUninitialize();
return; // Program has failed.
}
// Step 4: -----------------------------------------------------
// Connect to WMI through the IWbemLocator::ConnectServer method
IWbemServices* pSvc = NULL;
// Connect to the root\cimv2 namespace with
// the current user and obtain pointer pSvc
// to make IWbemServices calls.
hres = pLoc->ConnectServer(
_bstr_t(L"ROOT\\CIMV2"), // Object path of WMI namespace
NULL, // User name. NULL = current user
NULL, // User password. NULL = current
0, // Locale. NULL indicates current
NULL, // Security flags.
0, // Authority (for example, Kerberos)
0, // Context object
&pSvc // pointer to IWbemServices proxy
);
if (FAILED(hres))
{
std::cout << "Could not connect. Error code = 0x"
<< std::hex << hres << std::endl;
pLoc->Release();
CoUninitialize();
return; // Program has failed.
}
std::cout << "Connected to ROOT\\CIMV2 WMI namespace" << std::endl;
// Step 5: --------------------------------------------------
// Set security levels on the proxy -------------------------
hres = CoSetProxyBlanket(
pSvc, // Indicates the proxy to set
RPC_C_AUTHN_WINNT, // RPC_C_AUTHN_xxx
RPC_C_AUTHZ_NONE, // RPC_C_AUTHZ_xxx
NULL, // Server principal name
RPC_C_AUTHN_LEVEL_CALL, // RPC_C_AUTHN_LEVEL_xxx
RPC_C_IMP_LEVEL_IMPERSONATE, // RPC_C_IMP_LEVEL_xxx
NULL, // client identity
EOAC_NONE // proxy capabilities
);
if (FAILED(hres))
{
std::cout << "Could not set proxy blanket. Error code = 0x"
<< std::hex << hres << std::endl;
pSvc->Release();
pLoc->Release();
CoUninitialize();
return; // Program has failed.
}
// Step 6: --------------------------------------------------
// Use the IWbemServices pointer to make requests of WMI ----
// For example, get the name of the operating system
IEnumWbemClassObject* pEnumerator = NULL;
hres = pSvc->ExecQuery(
bstr_t("WQL"),
bstr_t("SELECT * FROM Win32_VideoController"),
WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY,
NULL,
&pEnumerator);
if (FAILED(hres))
{
std::cout << "Query for operating system name failed."
<< " Error code = 0x"
<< std::hex << hres << std::endl;
pSvc->Release();
pLoc->Release();
CoUninitialize();
return; // Program has failed.
}
// Step 7: -------------------------------------------------
// Get the data from the query in step 6 -------------------
IWbemClassObject* pclsObj = NULL;
ULONG uReturn = 0;
while (pEnumerator)
{
HRESULT hr = pEnumerator->Next(WBEM_INFINITE, 1,
&pclsObj, &uReturn);
if (0 == uReturn)
{
break;
}
VARIANT vtProp;
// Get the value of the Name property
hr = pclsObj->Get(L"Name", 0, &vtProp, 0, 0);
std::wcout << " OS Name : " << vtProp.bstrVal << std::endl;
VariantClear(&vtProp);
pclsObj->Release();
}
// Cleanup
// ========
pSvc->Release();
pLoc->Release();
pEnumerator->Release();
CoUninitialize();
}
int main(int argc, char* argv[])
{
auto adapters = GetDescriptionVRamDirectx();
int i = 1;
for (AdapterInfo adapter : adapters)
{
printf("Adapter %d:\n", i);
printf("-----------\n");
printf("Description :");
wprintf(adapter.description.c_str());
printf("\n");
printf("Video RAM :");
wprintf(L"%d", adapter.vRam);
printf("\n");
printf("Feature level :");
if (adapter.maxFeatureLevel == D3D_FEATURE_LEVEL_12_1)
printf("12_1\n");
else if (adapter.maxFeatureLevel == D3D_FEATURE_LEVEL_12_0)
printf("12_0\n");
else if (adapter.maxFeatureLevel == D3D_FEATURE_LEVEL_11_1)
printf("11_1\n");
else if (adapter.maxFeatureLevel == D3D_FEATURE_LEVEL_11_0)
printf("11_0\n");
else if (adapter.maxFeatureLevel == D3D_FEATURE_LEVEL_10_1)
printf("10_1\n");
else if (adapter.maxFeatureLevel == D3D_FEATURE_LEVEL_10_0)
printf("10_0\n");
else if (adapter.maxFeatureLevel == D3D_FEATURE_LEVEL_9_3)
printf("9_3\n");
else if (adapter.maxFeatureLevel == D3D_FEATURE_LEVEL_9_2)
printf("9_2\n");
else if (adapter.maxFeatureLevel == D3D_FEATURE_LEVEL_9_1)
printf("9_1\n");
else if (adapter.maxFeatureLevel == D3D_FEATURE_LEVEL_1_0_CORE)
printf("1_0_CORE\n");
printf("\n");
i++;
}
displayWMIAdapters();
printf("Press any key...\n");
getchar();
}
请注意，我还使用 WMI 来枚举显卡。所以在大多数设备上这都能正常工作，即：
Trying to enumerate graphics adapters...
Adapter 1:
-----------
Description :NVIDIA GeForce MX250
Video RAM :2080038912
Feature level :12_1
Adapter 2:
-----------
Description :Intel(R) UHD Graphics 620
Video RAM :134217728
Feature level :12_1
Adapter 3:
-----------
Description :Microsoft Basic Render Driver
Video RAM :0
Feature level :12_1
Connected to ROOT\CIMV2 WMI namespace
OS Name : Intel(R) UHD Graphics 620
OS Name : NVIDIA GeForce MX250
Press any key...
但是，我得到的信息是，在特定设置上，没有返回任何结果。比如我朋友说，
我的笔记本（资料不全，安装的显卡是2xGT755m in SLI plus standard，集成——一共3个）
Adapter 1:
-----------
Description :Microsoft Basic Render Driver
Video RAM :0
Feature level :12_1
Press any key...
我很难找出为什么我没有拿到所有卡片。此外，我不知道我可以执行什么样的调试来找出我的问题的原因。
为什么我在使用 DirectX API 时没有在所有机器上获得所有已安装的显卡？