SCRIPT_CONTROL structure (usp10.h)

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Contains script control flags for several Uniscribe functions, for example, ScriptItemize.

Syntax

typedef struct tag_SCRIPT_CONTROL {
  DWORD uDefaultLanguage : 16;
  DWORD fContextDigits : 1;
  DWORD fInvertPreBoundDir : 1;
  DWORD fInvertPostBoundDir : 1;
  DWORD fLinkStringBefore : 1;
  DWORD fLinkStringAfter : 1;
  DWORD fNeutralOverride : 1;
  DWORD fNumericOverride : 1;
  DWORD fLegacyBidiClass : 1;
  DWORD fMergeNeutralItems : 1;
  DWORD fUseStandardBidi : 1;
  DWORD fReserved : 6;
} SCRIPT_CONTROL;

Members

uDefaultLanguage

Primary language identifier for the language to use when Unicode values are ambiguous. This value is used in numeric processing to select digit shape when the fDigitSubstitute member of SCRIPT_STATE is set.

fContextDigits

Value indicating how national digits are selected. Possible values are defined in the following table.

Value Meaning
TRUE
 Choose national digits according to the nearest previous strong text.
FALSE
 Choose national digits according to the value of the uDefaultLanguage member.

fInvertPreBoundDir

Value indicating if the initial context is set to the opposite of the base embedding level, or to the base embedding level itself. Possible values are defined in the following table. The application sets this member to indicate that text at the start of the string defaults to being laid out as if it follows a strong left-to-right character if the base embedding level is 0, and as if it follows a strong right-to-left character if the base embedding level is 1. This member is used for GetCharacterPlacement legacy support.

Value Meaning
TRUE
 Change the initial context to the opposite of the base embedding level.
FALSE
 Set the initial context to the base embedding level.

fInvertPostBoundDir

Value indicating if the final context is set to the opposite of the base embedding level, or to the base embedding level itself. Possible values are defined in the following table. The application sets this member to indicate that text at the end of the string defaults to being laid out as if it precedes strong text of the same direction as the base embedding level. It is used for GetCharacterPlacement legacy support.

Value Meaning
TRUE
 Change the final context to the opposite of the base embedding level.
FALSE
 Set the final context to the base embedding level.

fLinkStringBefore

Value indicating if the shaping engine shapes the first character of the string as if it joins with a previous character. Possible values are defined in the following table.

Value Meaning
TRUE
 Shape the first character by linking with a previous character.
FALSE
 Do not shape the first character by linking with a previous character.

fLinkStringAfter

Value indicating if the shaping engine shapes the last character of the string as if it is joined to a subsequent character. Possible values are defined in the following table.

Value Meaning
TRUE
 Shape the last character by linking with a subsequent character.
FALSE
 Do not shape the last character by linking with a subsequent character.

fNeutralOverride

Value indicating the treatment of all neutral characters in the string. Possible values are defined in the following table.

Value Meaning
TRUE
 Set neutral items to a strong direction, that is, right-to-left or left-to-right, depending on the current embedding level. This setting effectively locks the items in place, and reordering occurs only between neutrals.
FALSE
 Do not set neutral items to a strong direction.

fNumericOverride

Value indicating the treatment of all numeric characters in the string. Possible values are defined in the following table.

Value Meaning
TRUE
 Set numeric characters to a strong direction, that is, right-to-left or left-to-right, depending on the current embedding level. This setting effectively locks the items in place, and reordering occurs only between numeric characters.
FALSE
 Do not set numeric characters to a strong direction.

fLegacyBidiClass

Value indicating the handling for plus and minus characters by the shaping engine. Possible values are defined in the following table.

Value Meaning
TRUE
 Treat the plus and minus characters as for legacy bidirectional classes in pre-Windows XP operating systems. In this case, the characters are treated as neutral characters, that is, with no implied direction, and the slash character is treated as a common separator.
FALSE
 Treat the plus and minus characters as for Windows XP and later. In this case, the characters are treated as European separators.

fMergeNeutralItems

Value specifying if the shaping engine should merge neutral characters into strong items when possible. Possible values are defined in the following table.

Value Meaning
TRUE
 Merge neutral characters into strong items.
FALSE
 Do not merge neutral characters into strong items.

fUseStandardBidi

Value specifying if the shaping engine should use the standard bidirectional matching pair algorithm. Possible values are defined in the following table.

Value Meaning
TRUE
 Skip the matching pair algorithm.
FALSE
 Use the matching pair algorithm.

fReserved

Reserved; always initialize to 0.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Header usp10.h
Redistributable Internet Explorer 5 or later onWindows Me/98/95

See also

Digit Shapes

SCRIPT_STATE

ScriptItemize

Uniscribe

Uniscribe Structures