typedef struct XDisplayHdrModeInfo {  
    float minToneMapLuminance;  
    float maxToneMapLuminance;  
    float maxFullFrameToneMapLuminance;  
} XDisplayHdrModeInfo  

void Game::InitializeHDRMode() 
{
    // Attempt to enable HDR mode, then initialize based on the 
    // result of the attempt.
    XDisplayHdrModeInfo displayModeHdrInfo;

    if (XDisplayHdrModeResult::Enabled == XDisplayTryEnableHdrMode(XDisplayHdrModePreference::PreferHdr, &displayModeHdrInfo))
    {
        // HDR mode is enabled for the attached display.
        InitializeAsHDR(
            displayModeHdrInfo.minToneMapLuminance,
            displayModeHdrInfo.maxToneMapLuminance,
            displayModeHdrInfo.maxFullFrameToneMapLuminance);
    }
    else
    {
        // Either HDR mode is disabled for the attached display, or the
        // attached display does not support HDR.
        InitializeAsSDR();
    }
}