IDWriteTextFormat::SetReadingDirection method (dwrite.h)

Article
02/22/2024

Sets the paragraph reading direction.

Syntax

HRESULT SetReadingDirection(
  DWRITE_READING_DIRECTION readingDirection
);

Parameters

readingDirection

Type: DWRITE_READING_DIRECTION

The text reading direction (for example, DWRITE_READING_DIRECTION_RIGHT_TO_LEFT for languages, such as Arabic, that read from right to left) for a paragraph.

Return value

Type: HRESULT

If this method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

Remarks

The reading direction and flow direction must always be set 90 degrees orthogonal to each other, or else you will get the error DWRITE_E_FLOWDIRECTIONCONFLICTS when you use layout functions like Draw or GetMetrics. So if you set a vertical reading direction (for example, to DWRITE_READING_DIRECTION_TOP_TO_BOTTOM), then you must also use SetFlowDirection to set the flow direction appropriately (for example, to DWRITE_FLOW_DIRECTION_RIGHT_TO_LEFT).

Requirements

Requirement	Value
Minimum supported client	Windows 7, Windows Vista with SP2 and Platform Update for Windows Vista [desktop apps \| UWP apps]
Minimum supported server	Windows Server 2008 R2, Windows Server 2008 with SP2 and Platform Update for Windows Server 2008 [desktop apps \| UWP apps]
Target Platform	Windows
Header	dwrite.h
Library	Dwrite.lib
DLL	Dwrite.dll