如何在 C++ 中使用 NvAPI_DISP_SetDisplayConfig 函数？

Question

我连续三次成功地使用 NvAPI_DISP_GetDisplayConfig 函数获取显示配置（如另一个线程中所述），现在想更改我的一个显示器的缩放选项。

但是，即使我尝试不更改任何设置（或仅更改缩放选项）并简单地应用检索到的 pathInfo，NvAPI_DISP_SetDisplayConfig 也会失败。有人知道为什么吗？

NvAPI_Status status = NVAPI_OK;
NvU32 deviceCount = 0;
NV_DISPLAYCONFIG_PATH_INFO_V2 *  pathInfo = NULL;

status = NvAPI_Initialize();

if (status == NVAPI_OK) {
status = NvAPI_DISP_GetDisplayConfig(&deviceCount, pathInfo);
if ((status == NVAPI_OK) && (deviceCount > 0)) {

    printf("\nFirst pass ok. \n");
    pathInfo = new NV_DISPLAYCONFIG_PATH_INFO_V2[deviceCount];

    for (int i = 0; i < deviceCount; i++)
    {
        pathInfo[i].targetInfo = 0;
        pathInfo[i].targetInfoCount = 0;
        pathInfo[i].version = NV_DISPLAYCONFIG_PATH_INFO_VER2;
        pathInfo[i].sourceModeInfo = 0;
        pathInfo[i].reserved = 0;
    }

    status = NvAPI_DISP_GetDisplayConfig(&deviceCount, pathInfo);

    if (status == NVAPI_OK) {

         printf("\nSecond pass ok. \n");
        for (int i = 0; i < deviceCount; i++)
        {
            pathInfo[i].sourceModeInfo = new NV_DISPLAYCONFIG_SOURCE_MODE_INFO_V1;
            pathInfo[i].sourceModeInfo->reserved = 0;
            pathInfo[i].targetInfo = new NV_DISPLAYCONFIG_PATH_TARGET_INFO_V2[pathInfo[i].targetInfoCount];
            for (int j = 0; j < pathInfo[i].targetInfoCount; j++) {
                pathInfo[i].targetInfo[j].details = new NV_DISPLAYCONFIG_PATH_ADVANCED_TARGET_INFO_V1;
                            pathInfo[i].targetInfo[j].details->version = NV_DISPLAYCONFIG_PATH_ADVANCED_TARGET_INFO_VER1;
                pathInfo[i].targetInfo[j].details->reserved = 0;
            }
        }
    }

    status = NvAPI_DISP_GetDisplayConfig(&deviceCount, pathInfo);
    if (status == NVAPI_OK) {
          printf("\nThird pass ok. \n");
    }

      for (int i = 0; i < deviceCount; i++)
        { 
            for (int j = 0; j < pathInfo[i].targetInfoCount; j++) {
                switch(pathInfo[i].targetInfo[j].details->scaling)
                {
                case NV_SCALING_DEFAULT:
                    printf("Default");
                    break;
                case NV_SCALING_GPU_SCALING_TO_CLOSEST:
                    printf("GPU Scaling to closest");
                    break;
                case NV_SCALING_GPU_SCALING_TO_NATIVE :
                    printf("GPU scaling to native");
                    break;
                case NV_SCALING_GPU_SCANOUT_TO_NATIVE :
                    printf("Gpu scanout to native");
                    break;
                case NV_SCALING_GPU_SCALING_TO_ASPECT_SCANOUT_TO_NATIVE :
                    printf("GPU scaling to aspect scanout to native");
                    break;
                case NV_SCALING_GPU_SCALING_TO_ASPECT_SCANOUT_TO_CLOSEST :
                    printf("Gpu scaling to aspect scanout to closest");
                    break;
                case NV_SCALING_GPU_SCANOUT_TO_CLOSEST :
                    printf("Gpu scanout to closest");
                    break;
                case NV_SCALING_CUSTOMIZED :
                    printf("Scaling customized");
                default:
                    printf("Nothing");
                    break;
               }             
            }     
        }

    //FAILS !!!!!!!!!!
      status = NvAPI_DISP_SetDisplayConfig(deviceCount,pathInfo,NV_DISPLAYCONFIG_VALIDATE_ONLY  );
    }

}

任何帮助将不胜感激，非常感谢！

Answer 1

您似乎只是提到 SetDisplayConfig 失败...它可能有助于解决您的问题确切知道什么是错的...您能否给出具体错误：例如，这是取自NVAPI programming documentation：

/*
This function is used to print to the command line a text message
describing the nvapi error and quits
*/
void PrintError(NvAPI_Status status)
{
    NvAPI_ShortString
    szDesc = {0};
    NvAPI_GetErrorMessage
    (status, szDesc);
    printf(" NVAPI error: %s\n", szDesc);
    exit(-1);
}

Answer 2

这是因为IsNonNVIDIAAdapter设置为true，但是pOSAdapterID没有传入。 如果你确定你有一个 nVidia 显卡，在使用前对 pathInfo 做ZeroMemory()。