Example code for displaying an app on a portrait device
Here is code that you can use to make your app display correctly on a portrait device.
//
// This file contains utility functions for use in desktop applications for getting the current
// orientation as Landscape/Portrait/LandscapeFlipped/PortraitFlipped (abbr: L/P/LF/PF). These
// functions are most helpful for use with APIs which expect one of these values, while the APIs
// for retrieving all return the rotation in degrees (0/90/180/270). There is not a direct mapping
// between these two forms since 0 degrees means portrait on portrait-native devices and landscape
// on landscape-native devices.
//
#include <windows.h>
#include <iostream>
enum ORIENTATION
{
INVALID,
LANDSCAPE,
PORTRAIT,
LANDSCAPE_FLIPPED,
PORTRAIT_FLIPPED
};
// Maps the current rotation from 0/90/180/270 to L/P/LF/PF using the unrotated
// resolution to guess at what the native orientation is.
ORIENTATION GetOrientationFromCurrentMode(_In_ PCWSTR pszDeviceName)
{
DEVMODEW CurrentMode = {};
CurrentMode.dmSize = sizeof(CurrentMode);
if (!EnumDisplaySettingsW(pszDeviceName,
ENUM_CURRENT_SETTINGS,
&CurrentMode))
{
// Error condition, likely invalid device name, could log error
// HRESULT hr = HRESULT_FROM_WIN32(GetLastError());
return INVALID;
}
if ((CurrentMode.dmDisplayOrientation == DMDO_90) ||
(CurrentMode.dmDisplayOrientation == DMDO_270))
{
DWORD temp = CurrentMode.dmPelsHeight;
CurrentMode.dmPelsHeight = CurrentMode.dmPelsWidth;
CurrentMode.dmPelsWidth = temp;
}
if (CurrentMode.dmPelsWidth < CurrentMode.dmPelsHeight)
{
switch (CurrentMode.dmDisplayOrientation)
{
case DMDO_DEFAULT: return PORTRAIT;
case DMDO_90: return LANDSCAPE_FLIPPED;
case DMDO_180: return PORTRAIT_FLIPPED;
case DMDO_270: return LANDSCAPE;
default: return INVALID;
}
}
else
{
switch (CurrentMode.dmDisplayOrientation)
{
case DMDO_DEFAULT: return LANDSCAPE;
case DMDO_90: return PORTRAIT;
case DMDO_180: return LANDSCAPE_FLIPPED;
case DMDO_270: return PORTRAIT_FLIPPED;
default: return INVALID;
}
}
}
// Overloaded function accepts an HMONITOR and converts to DeviceName
ORIENTATION GetOrientationFromCurrentMode(HMONITOR hMonitor)
{
// Get the name of the 'monitor' being requested
MONITORINFOEXW ViewInfo;
RtlZeroMemory(&ViewInfo, sizeof(ViewInfo));
ViewInfo.cbSize = sizeof(ViewInfo);
if (!GetMonitorInfoW(hMonitor, &ViewInfo))
{
// Error condition, likely invalid monitor handle, could log error
// HRESULT hr = HRESULT_FROM_WIN32(GetLastError());
return INVALID;
}
else
{
return GetOrientationFromCurrentMode(ViewInfo.szDevice);
}
}
// Returns true if this is an integrated display panel e.g. the screen attached to tablets or laptops.
bool IsInternalVideoOutput(const DISPLAYCONFIG_VIDEO_OUTPUT_TECHNOLOGY VideoOutputTechnologyType)
{
switch (VideoOutputTechnologyType)
{
case DISPLAYCONFIG_OUTPUT_TECHNOLOGY_INTERNAL:
case DISPLAYCONFIG_OUTPUT_TECHNOLOGY_DISPLAYPORT_EMBEDDED:
case DISPLAYCONFIG_OUTPUT_TECHNOLOGY_UDI_EMBEDDED:
return TRUE;
default:
return FALSE;
}
}
// Given a target on an adapter, returns whether it is a natively portrait display
bool IsNativeOrientationPortrait(const LUID AdapterLuid, const UINT32 TargetId)
{
DISPLAYCONFIG_TARGET_PREFERRED_MODE PreferredMode;
PreferredMode.header.type = DISPLAYCONFIG_DEVICE_INFO_GET_TARGET_PREFERRED_MODE;
PreferredMode.header.size = sizeof(PreferredMode);
PreferredMode.header.adapterId = AdapterLuid;
PreferredMode.header.id = TargetId;
HRESULT hr = HRESULT_FROM_WIN32(DisplayConfigGetDeviceInfo(&PreferredMode.header));
if (FAILED(hr))
{
// Error condition, assume natively landscape
return false;
}
return (PreferredMode.height > PreferredMode.width);
}
// Note: Since an hmon can represent multiple monitors while in clone, this function as written will return
// the value for the internal monitor if one exists, and otherwise the highest clone-path priority.
HRESULT GetPathInfo(_In_ PCWSTR pszDeviceName, _Out_ DISPLAYCONFIG_PATH_INFO* pPathInfo)
{
HRESULT hr = S_OK;
UINT32 NumPathArrayElements = 0;
UINT32 NumModeInfoArrayElements = 0;
DISPLAYCONFIG_PATH_INFO* PathInfoArray = nullptr;
DISPLAYCONFIG_MODE_INFO* ModeInfoArray = nullptr;
do
{
// In case this isn't the first time through the loop, delete the buffers allocated
delete[] PathInfoArray;
PathInfoArray = nullptr;
delete[] ModeInfoArray;
ModeInfoArray = nullptr;
hr = HRESULT_FROM_WIN32(GetDisplayConfigBufferSizes(QDC_ONLY_ACTIVE_PATHS, &NumPathArrayElements, &NumModeInfoArrayElements));
if (FAILED(hr))
{
break;
}
PathInfoArray = new(std::nothrow) DISPLAYCONFIG_PATH_INFO[NumPathArrayElements];
if (PathInfoArray == nullptr)
{
hr = E_OUTOFMEMORY;
break;
}
ModeInfoArray = new(std::nothrow) DISPLAYCONFIG_MODE_INFO[NumModeInfoArrayElements];
if (ModeInfoArray == nullptr)
{
hr = E_OUTOFMEMORY;
break;
}
hr = HRESULT_FROM_WIN32(QueryDisplayConfig(QDC_ONLY_ACTIVE_PATHS, &NumPathArrayElements, PathInfoArray, &NumModeInfoArrayElements, ModeInfoArray, nullptr));
}while (hr == HRESULT_FROM_WIN32(ERROR_INSUFFICIENT_BUFFER));
INT DesiredPathIdx = -1;
if (SUCCEEDED(hr))
{
// Loop through all sources until the one which matches the 'monitor' is found.
for (UINT PathIdx = 0; PathIdx < NumPathArrayElements; ++PathIdx)
{
DISPLAYCONFIG_SOURCE_DEVICE_NAME SourceName = {};
SourceName.header.type = DISPLAYCONFIG_DEVICE_INFO_GET_SOURCE_NAME;
SourceName.header.size = sizeof(SourceName);
SourceName.header.adapterId = PathInfoArray[PathIdx].sourceInfo.adapterId;
SourceName.header.id = PathInfoArray[PathIdx].sourceInfo.id;
hr = HRESULT_FROM_WIN32(DisplayConfigGetDeviceInfo(&SourceName.header));
if (SUCCEEDED(hr))
{
if (wcscmp(pszDeviceName, SourceName.viewGdiDeviceName) == 0)
{
// Found the source which matches this hmonitor. The paths are given in path-priority order
// so the first found is the most desired, unless we later find an internal.
if (DesiredPathIdx == -1 || IsInternalVideoOutput(PathInfoArray[PathIdx].targetInfo.outputTechnology))
{
DesiredPathIdx = PathIdx;
}
}
}
}
}
if (DesiredPathIdx != -1)
{
*pPathInfo = PathInfoArray[DesiredPathIdx];
}
else
{
hr = E_INVALIDARG;
}
delete[] PathInfoArray;
PathInfoArray = nullptr;
delete[] ModeInfoArray;
ModeInfoArray = nullptr;
return hr;
}
// Overloaded function accepts an HMONITOR and converts to DeviceName
HRESULT GetPathInfo(HMONITOR hMonitor, _Out_ DISPLAYCONFIG_PATH_INFO* pPathInfo)
{
HRESULT hr = S_OK;
// Get the name of the 'monitor' being requested
MONITORINFOEXW ViewInfo;
RtlZeroMemory(&ViewInfo, sizeof(ViewInfo));
ViewInfo.cbSize = sizeof(ViewInfo);
if (!GetMonitorInfoW(hMonitor, &ViewInfo))
{
// Error condition, likely invalid monitor handle, could log error
hr = HRESULT_FROM_WIN32(GetLastError());
}
if (SUCCEEDED(hr))
{
hr = GetPathInfo(ViewInfo.szDevice, pPathInfo);
}
return hr;
}
// Note: Function return S_FALSE if there is no internal target
// Gets the path info for the integrated display panel e.g. the screen attached to tablets or laptops.
HRESULT GetPathInfoForInternal(_Out_ DISPLAYCONFIG_PATH_INFO* pPathInfo)
{
HRESULT hr = S_OK;
UINT32 NumPathArrayElements = 0;
UINT32 NumModeInfoArrayElements = 0;
DISPLAYCONFIG_PATH_INFO* PathInfoArray = nullptr;
DISPLAYCONFIG_MODE_INFO* ModeInfoArray = nullptr;
do
{
// In case this isn't the first time through the loop, delete the buffers allocated
delete[] PathInfoArray;
PathInfoArray = nullptr;
delete[] ModeInfoArray;
ModeInfoArray = nullptr;
hr = HRESULT_FROM_WIN32(GetDisplayConfigBufferSizes(QDC_ONLY_ACTIVE_PATHS, &NumPathArrayElements, &NumModeInfoArrayElements));
if (FAILED(hr))
{
break;
}
PathInfoArray = new(std::nothrow) DISPLAYCONFIG_PATH_INFO[NumPathArrayElements];
if (PathInfoArray == nullptr)
{
hr = E_OUTOFMEMORY;
break;
}
ModeInfoArray = new(std::nothrow) DISPLAYCONFIG_MODE_INFO[NumModeInfoArrayElements];
if (ModeInfoArray == nullptr)
{
hr = E_OUTOFMEMORY;
break;
}
hr = HRESULT_FROM_WIN32(QueryDisplayConfig(QDC_ONLY_ACTIVE_PATHS, &NumPathArrayElements, PathInfoArray, &NumModeInfoArrayElements, ModeInfoArray, nullptr));
}while (hr == HRESULT_FROM_WIN32(ERROR_INSUFFICIENT_BUFFER));
if (SUCCEEDED(hr))
{
hr = S_FALSE;
RtlZeroMemory(pPathInfo, sizeof(*pPathInfo));
for (UINT PathIdx = 0; PathIdx < NumPathArrayElements; ++PathIdx)
{
if (IsInternalVideoOutput(PathInfoArray[PathIdx].targetInfo.outputTechnology))
{
// There's only one internal target on the system and we found it.
*pPathInfo = PathInfoArray[PathIdx];
hr = S_OK;
break;
}
}
}
delete[] PathInfoArray;
PathInfoArray = nullptr;
delete[] ModeInfoArray;
ModeInfoArray = nullptr;
return hr;
}
// Given a path info, this function will find the native orientation of the path and map 0/90/180/270 to L/P/LF/PF
ORIENTATION GetOrientationFromPathInfo(_In_ const DISPLAYCONFIG_PATH_INFO* const pPathInfo)
{
bool IsNativelyPortrait = IsNativeOrientationPortrait(pPathInfo->targetInfo.adapterId, pPathInfo->targetInfo.id);
DISPLAYCONFIG_ROTATION CurrentRotation = pPathInfo->targetInfo.rotation;
if (IsNativelyPortrait)
{
switch (CurrentRotation)
{
case DISPLAYCONFIG_ROTATION_IDENTITY: return PORTRAIT;
case DISPLAYCONFIG_ROTATION_ROTATE90: return LANDSCAPE_FLIPPED;
case DISPLAYCONFIG_ROTATION_ROTATE180: return PORTRAIT_FLIPPED;
case DISPLAYCONFIG_ROTATION_ROTATE270: return LANDSCAPE;
default: return INVALID;
}
}
else
{
switch (CurrentRotation)
{
case DISPLAYCONFIG_ROTATION_IDENTITY: return LANDSCAPE;
case DISPLAYCONFIG_ROTATION_ROTATE90: return PORTRAIT;
case DISPLAYCONFIG_ROTATION_ROTATE180: return LANDSCAPE_FLIPPED;
case DISPLAYCONFIG_ROTATION_ROTATE270: return PORTRAIT_FLIPPED;
default: return INVALID;
}
}
}
// This function shows the use of each of the utility functions found above in a reasonable order of calling.
ORIENTATION GetOrientation(bool UseInternal)
{
DISPLAYCONFIG_PATH_INFO PathInfo = {};
HMONITOR hPrimaryMon = MonitorFromWindow(NULL, MONITOR_DEFAULTTOPRIMARY);
HRESULT hr = S_FALSE;
if (UseInternal)
{
hr = GetPathInfoForInternal(&PathInfo);
}
if ((hr == S_FALSE) || FAILED(hr))
{
// Could log an error on FAILED(hr), but whether legitimate failure or desktop system, try the primary monitor
hr = GetPathInfo(hPrimaryMon, &PathInfo);
}
if (SUCCEEDED(hr))
{
return GetOrientationFromPathInfo(&PathInfo);
}
else
{
// In Windows 8.1 and previous operating systems, the GetPathInfo (and ForInternal) call will fail in a remote session,
// falling back to checking the current mode is the most appropriate thing to do in this situation.
return GetOrientationFromCurrentMode(hPrimaryMon);
}
}
void PrintOrientation(ORIENTATION Orientation)
{
switch (Orientation)
{
case INVALID: std::cout << "Error" << std::endl; break;
case LANDSCAPE: std::cout << "Landscape" << std::endl; break;
case PORTRAIT: std::cout << "Portrait" << std::endl; break;
case LANDSCAPE_FLIPPED: std::cout << "Landscape Flipped" << std::endl; break;
case PORTRAIT_FLIPPED: std::cout << "Portrait Flipped" << std::endl; break;
}
}
int __cdecl main(int argc, const char* argv[])
{
UNREFERENCED_PARAMETER(argc);
UNREFERENCED_PARAMETER(argv);
HRESULT hr = E_FAIL;
// Note: This MonitorFromWindow call should be modified if the orientation is needed for
// the monitor the application's window is currently on. It is also unnecessary if only
// the internal monitor is desired.
HMONITOR hPrimaryMon = MonitorFromWindow(NULL, MONITOR_DEFAULTTOPRIMARY);
// Print the orientation of the integrated panel.
{
DISPLAYCONFIG_PATH_INFO PathInfo = {};
hr = GetPathInfoForInternal(&PathInfo);
if (hr == S_FALSE)
{
std::cout << "No integrated panel found." << std::endl;
}
else if (SUCCEEDED(hr))
{
std::cout << "Integrated panel: ";
PrintOrientation(GetOrientationFromPathInfo(&PathInfo));
}
else
{
std::cout << "Error looking for internal monitor: " << hr << std::endl;
}
}
// Print the orientation of the primary monitor.
{
DISPLAYCONFIG_PATH_INFO PathInfo = {};
hr = GetPathInfo(hPrimaryMon, &PathInfo);
if (SUCCEEDED(hr))
{
std::cout << "Primary monitor: ";
PrintOrientation(GetOrientationFromPathInfo(&PathInfo));
}
else
{
std::cout << "Error getting path info for primary monitor: " << hr << std::endl;
}
}
// In Windows 8.1 and previous operating systems, GetPathInfo (and GetPathInfoForInternal) will fail in a remote
// session, falling back to checking the current mode is the most appropriate thing to do in this situation.
if (FAILED(hr))
{
std::cout << "Fallback based on current mode: ";
PrintOrientation(GetOrientationFromCurrentMode(hPrimaryMon));
}
}
Feedback
Coming soon: Throughout 2024 we will be phasing out GitHub Issues as the feedback mechanism for content and replacing it with a new feedback system. For more information see: https://aka.ms/ContentUserFeedback.
Submit and view feedback for