Ideographic Description Characters is a
Unicode block containing graphic characters used for describing
CJK ideographs. They are used in
Ideographic Description Sequences (IDS) to provide a description of an ideograph, in terms of what other ideographs make it up and how they are laid out relative to one another.
[IDS are described i]
chapter 18.2 of the Unicode Standard 9.0
on pages 689 through 692. An IDS provides the reader with a description of an ideograph that cannot be represented properly, usually because it is not encoded in Unicode; rendering systems are not intended to automatically compose the pieces into a complete ideograph, and the descriptions are not standardized.
U+2FF0 to U+2FFB were introduced from
GBK; U+2FFC to U+2FFF were devised later and introduced in Unicode 15.1 (2023).
Block
Ideographic Description Sequences
Ideographic Description Sequences are sequences of characters that represent a Chinese character structure as defined by the Unicode standard.
Below are the 16 characters as defined by Unicode in this block:
Two other related ideographic description characters are not encoded in this Unicode block, but of which may be used in ideographic description sequences:
This is the syntax of IDS in
EBNF:
IDS := Ideographic , Radical , CJK_Stroke , Private Use , U+FF1F , IDS_UnaryOperator IDS , IDS_BinaryOperator IDS IDS , IDS_TrinaryOperator IDS IDS IDS
CJK_Stroke := U+31C0 , U+31C1 , ... , U+31E3
IDS_UnaryOperator := U+2FFE , U+2FFF
IDS_BinaryOperator := U+2FF0 , U+2FF1 , U+2FF4 , ... , U+2FFD , U+31EF
IDS_TrinaryOperator:= U+2FF2 , U+2FF3
History
The following Unicode-related documents record the purpose and process of defining specific characters in the Ideographic Description Characters block:
See also
*
Chinese character description languages
*
Specials (Unicode block)
References
{{CJK ideographs in Unicode
Unicode blocks