ScriptGetFontScriptTags function (usp10.h)

Article
10/13/2021

Retrieves a list of scripts available in the font for OpenType processing. Scripts comprising the list are retrieved from the font located in the supplied device context or from the script shaping engine that processes the font of the current run.

Syntax

HRESULT ScriptGetFontScriptTags(
  [in, optional] HDC             hdc,
  [in, out]      SCRIPT_CACHE    *psc,
  [in, optional] SCRIPT_ANALYSIS *psa,
  [in]           int             cMaxTags,
  [out]          OPENTYPE_TAG    *pScriptTags,
  [out]          int             *pcTags
);

Parameters

[in, optional] hdc

Handle to the device context. For more information, see Caching.

[in, out] psc

Pointer to a SCRIPT_CACHE structure identifying the script cache.

[in, optional] psa

Pointer to a SCRIPT_ANALYSIS structure obtained from a previous call to ScriptItemizeOpenType. This parameter identifies the shaping engine, so that the appropriate font script tags can be retrieved. The application supplies a non-NULL value for this parameter to retrieve script tags appropriate for the current run.

Alternatively, the application can set this parameter to NULL to retrieve unfiltered results.

[in] cMaxTags

The length of the array specified by pScriptTags.

[out] pScriptTags

Pointer to a buffer in which this function retrieves an array of OPENTYPE_TAG structures defining script tags from the device context or the scripting engine associated with the current run. If the value of the eScript member of the SCRIPT_ANALYSIS structure provided in the psa parameter has a definite script tag associated with it and the tag is present in the font, pScriptTags contains only this tag.

[out] pcTags

Pointer to the number of elements in the script tag array indicated by pScriptTags.

Return value

Returns 0 if successful. The function returns a nonzero HRESULT value if it does not succeed. The application can test the return value with the SUCCEEDED and FAILED macros.

If the number of matching tags exceeds the value of cMaxTags, the function fails with E_OUTOFMEMORY. The application can try calling again with larger buffers.

Remarks

While formally declared as a ULONG type, OPENTYPE_TAG defines a 4-byte array that contains four 8-bit ASCII values of space, A-Z or a-z. For example, the script tags for Latin and Arabic scripts are "latn" and "arab", respectively.

This function retrieves a single tag from a font in the following cases:

The psa value is associated with text for a single complex script.
The psa parameter indicates NULL and the font supports a single script.

If ScriptGetFontScriptTags retrieves all tags from a font, the tags are usually for neutral items, such as digits. Note that more than one tag might be applicable because some text runs of neutral items are not script-specific.

If a tag corresponding to a particular script is present, a shaping engine might be unable to use the font to shape the given item because the engine lacks a needed item, such as a specific language system or a specific feature.

Important Starting with Windows 8: To maintain the ability to run on Windows 7, a module that uses Uniscribe must specify Usp10.lib before gdi32.lib in its library list.

Requirements

Requirement	Value
Minimum supported client	Windows Vista [desktop apps only]
Minimum supported server	Windows Server 2008 [desktop apps only]
Target Platform	Windows
Header	usp10.h
Library	Usp10.lib
DLL	Usp10.dll
Redistributable	Usp10.dll version 1.600 or greater on Windows XP