Ideographic Description Characters (Unicode block)

Last updated
Ideographic Description Characters
RangeU+2FF0..U+2FFF
(16 code points)
Plane BMP
Scripts Common
Assigned16 code points
Unused0 reserved code points
Source standards GBK (U+2FF0–U+2FFB only)
Unicode version history
3.0 (1999)12 (+12)
15.1 (2023)16 (+4)
Unicode documentation
Code chart ∣ Web page
Note: [1] [2]

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. [3] 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.

Contents

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 Characters [1]
Official Unicode Consortium code chart (PDF)
 0123456789ABCDEF
U+2FFx⿿
Notes
1. ^ As of Unicode version 15.1

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:

UnicodeCharMeaningExample 1IDSExample 2IDS
U+2FF0Two components combined left to right⿰木目𠁢⿰丨㇍
U+2FF1Two components combined above to below⿱木口𠚤⿱𠂊丶
U+2FF2Three components combined left to middle and right⿲彳氵亍𠂗⿲丿夕乚
U+2FF3Three components combined above to middle and below⿳亠口小𠋑⿳亼目口
U+2FF4One component fully wrapping another component⿴囗口𠀬⿴㐁人
U+2FF5One component surround three sides of another component (opening at bottom)⿵几皇𧓉⿵齊虫
U+2FF6One component surround three sides of another component (opening at top)⿶凵㐅⿶乂丶
U+2FF7One component surround three sides of another component (opening at right)⿷匚斤𧆬⿷虎九
U+2FF8One component surround top and left side of another component⿸疒丙𤆯⿸耂火
U+2FF9One component surround top and right side of another component⿹戈廾𢧌⿹或壬
U+2FFAOne component surround bottom and left side of another component⿺走召𥘶⿺礼分
U+2FFBTwo components overlapped⿻工从𣏃⿻木⿻コ一
U+2FFCOne component surround three sides of another component (opening at left)⿼叉丶𬺹⿼コ二
U+2FFDOne component surround bottom and right side of another component⿽水丶⿽⺀十
U+2FFEHorizontal reflection⿾卍𣥄⿾正
U+2FFF⿿Rotation𠕄⿿凹𠄔⿿予

Two other related ideographic description characters are not encoded in this Unicode block, but of which may be used in ideographic description sequences:

UnicodeCharBlockMeaningExample 1IDSExample 2IDS
U+303E CJK Symbols and Punctuation Variant but not equivalent㬵 (U+3B35)〾胶 (U+80F6) [4] 𫜵〾爫 [5]
U+31EF CJK Strokes Subtraction㇯兵丶𧰨㇯豕一


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+31E3IDS_UnaryOperator :=U+2FFE |U+2FFFIDS_BinaryOperator :=U+2FF0 |U+2FF1 |U+2FF4 |...|U+2FFD |U+31EFIDS_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:

Version Final code points [lower-alpha 1] Count UTC  ID L2  ID WG2  ID IRG  IDDocument
3.0U+2FF0..2FFB12X3L2/95-111N1284Ideographic Structure Symbol (additional request), 1995-11-07
N1303 (html, doc)Umamaheswaran, V. S.; Ksar, Mike (1996-01-26), "8.13 Ideographic structure symbols", Minutes of Meeting 29, Tokyo
N1348Ideographic Components and Composition Scheme, 1996-02-05
N1357Revised Ideographic Structure Symbols, 1996-04-12
N1353 Umamaheswaran, V. S.; Ksar, Mike (1996-06-25), "9", Draft minutes of WG2 Copenhagen Meeting # 30
L2/97-026N1494IRG proposal: Ideographic structure character, 1996-06-27
N1430N365Proposal Summary Form: Ideographic Structure Character, 1996-08-01
N1453 Ksar, Mike; Umamaheswaran, V. S. (1996-12-06), "9.6 Ideographic Structure Characters", WG 2 Minutes - Quebec Meeting 31
L2/97-023N1486 N437 IRG #8 Resolutions, 1997-01-16
N1489Supplement to Ideographic Components and Composition Schemes, 1997-01-16
N1490 N436 Response to WG2 question on Ideographic Structure Characters, 1997-01-16
L2/97-030 N1503 (pdf, doc)Umamaheswaran, V. S.; Ksar, Mike (1997-04-01), "9.6", Unconfirmed Minutes of WG 2 Meeting #32, Singapore; 1997-01-20--24
L2/97-114 N1544 (html, doc) N453 Sato, T. K. (1997-04-08), Questions on the "Han structure method" described in WG2 N1490 (IRG N436)
L2/97-255R Aliprand, Joan (1997-12-03), "4.B.2 Ideographic Structure Characters", Approved Minutes – UTC #73 & L2 #170 joint meeting, Palo Alto, CA – August 4-5, 1997
N1680 Project Sub-Division Proposal on Scheme of Ideograph Description Sequence, 1997-12-18
N1782 Clause X Ideographic Description Sequence (IDS) – IRG N575, 1998-05-06
L2/98-158 Aliprand, Joan; Winkler, Arnold (1998-05-26), "SC2 SC2 Action re Ideographic Description Sequences", Draft Minutes – UTC #76 & NCITS Subgroup L2 #173 joint meeting, Tredyffrin, Pennsylvania, April 20-22, 1998
N1842 Proposed text for a Draft for amendment 28 - Ideographic Description Sequences, 1998-06-03
L2/98-286 N1703 Umamaheswaran, V. S.; Ksar, Mike (1998-07-02), "9.5", Unconfirmed Meeting Minutes, WG 2 Meeting #34, Redmond, WA, USA; 1998-03-16--20, The original proposal was to use character composition. It has changed from being composition to description over its three year development.
L2/98-317 N1892 (pdf, doc)Combined CD registration and consideration ballot on WD for 10646-1/Amd. 28, AMENDMENT 28: Ideographic description characters, 1998-10-22
L2/99-010 N1903 (pdf, html, doc)Umamaheswaran, V. S. (1998-12-30), "10.3", Minutes of WG 2 meeting 35, London, U.K.; 1998-09-21--25
L2/99-072.1 N1971 Irish Comments on SC 2 N 3186, 1999-01-19
L2/99-072 N1970 (html, doc)Summary of Voting on SC 2 N 3186, PDAM ballot on WD for 10646-1/Amd. 28: Ideographic description characters, 1999-02-05
N2023 Paterson, Bruce (1999-04-06), FPDAM 28 Text - Ideographic Description Characters
L2/99-120 Text for FPDAM ballot of ISO/IEC 10646, Amd. 28 - Ideographic description characters, 1999-04-07
UTC/1999-014 Jenkins, John (1999-06-01), Recursion depth limit for IDC's
UTC/1999-015 Whistler, Ken (1999-06-01), Re: Brief note on length of ideograph descriptions
UTC/1999-020 Jenkins, John (1999-06-04), Diagram and language [for Ideograph Description Sequences]
L2/99-176R Moore, Lisa (1999-11-04), "Recursion Limit for Ideographic Description Characters", Minutes from the joint UTC/L2 meeting in Seattle, June 8-10, 1999
L2/99-232 N2003 Umamaheswaran, V. S. (1999-08-03), "6.1.2 PDAM28 - Ideographic Description Characters", Minutes of WG 2 meeting 36, Fukuoka, Japan, 1999-03-09--15
L2/99-253 N2067 Summary of Voting on SC 2 N 3312, ISO 10646-1/FPDAM 28 - Ideographic description characters, 1999-08-19
L2/99-301 N2123 Disposition of Comments Report on SC 2 N 3312, ISO/IEC 10646-1/FPDAM 28, AMENDMENT 28: Ideographic description characters, 1999-09-20
L2/99-302 N2124 Paterson, Bruce (1999-09-24), Revised Text for FDAM ballot of ISO/IEC 10646-1/FDAM 28, AMENDMENT 28: Ideographic description characters
L2/00-010 N2103 Umamaheswaran, V. S. (2000-01-05), "6.4.3", Minutes of WG 2 meeting 37, Copenhagen, Denmark: 1999-09-13—16
L2/00-045 Summary of FDAM voting: ISO 10646 Amd. 28: Ideographic description characters, 2000-01-31
L2/02-221 N2480 Cook, Richard (2002-05-18), Proposal to add Ideographic Description Characters (IDC) to the UCS
L2/02-436 N2534 N955IRG Radical Classification, 2002-11-21
L2/12-087 Proposed Changes to ISO/IEC 10646 Annex I, Ideographic Description Characters, 2012-02-09
L2/12-007 Moore, Lisa (2012-02-14), "Consensus 130-C13", UTC #130 / L2 #227 Minutes, Submit L2/12-087 on extensions to ideographic description sequences to WG2.
L2/15-065 Jenkins, John (2015-02-02), Proposal to Add IDS Links to Online Unihan Database
L2/15-070 Davis, Mark (2015-02-03), IDS in Unihan
L2/15-313 Lunde, Ken (2015-11-03), Request for IDS Data
15.1U+2FFC..2FFF4 L2/17-386 N2273 Yang, Tao; Chan, Eiso; Wang, Yifan (2017-10-13), Submission of 3 IDCes
L2/17-379 Lunde, Ken (2017-10-20), "Proposed Ideographic Description Characters (IDCs)", IRG #49 Liaison Report
L2/18-012 Yang, Tao; Chan, Eiso; Wang, Yifan (2018-01-05), Proposal of Four IDCs
L2/18-168 Anderson, Deborah; Whistler, Ken; Pournader, Roozbeh; Moore, Lisa; Liang, Hai; Chapman, Chris; Cook, Richard (2018-04-28), "22. IDCs", Recommendations to UTC #155 April-May 2018 on Script Proposals
L2/21-118R N2492Lunde, Ken; Jenkins, John H. (2021-08-11), Preliminary proposal to add a new provisional kIDS property (Unihan)
L2/22-136 West, Andrew (2022-07-08), Feedback on Proposals to Encode New Ideographic Description Characters
L2/22-191 N2572Lunde, Ken; Jenkins, John; West, Andrew (2022-08-24), Proposal to encode five new Ideographic Description Characters
L2/22-227 SAT Feedback to "Preliminary proposal to add a new provisional kIDS property (Unihan)" (IRGN2492) and "Proposal to encode five new Ideographic Description Characters" (IRGN2572), 2022-08-29
L2/22-228 Fan, Ming (2022-09-02), Feedback on IRGN2572 "Proposal to encode 5 new ideograph description characters"
L2/22-247 Lunde, Ken (2022-11-01), "29", CJK & Unihan Group Recommendations for UTC #173 Meeting
L2/22-241 Constable, Peter (2022-11-09), "E.1 29", Approved Minutes of UTC Meeting 173
  1. Proposed code points and characters names may differ from final code points and names

See also

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References

  1. "Unicode character database". The Unicode Standard. Retrieved 2023-07-26.
  2. "Enumerated Versions of The Unicode Standard". The Unicode Standard. Retrieved 2023-07-26.
  3. IDS are described in chapter 18.2 of the Unicode Standard 9.0 on pages 689 through 692.
  4. "「㬵(U+3B35)」和「胶(U+80F6)」为什么在《康熙字典》收录了两次? - 知乎". www.zhihu.com. Retrieved 2023-09-21.
  5. "基本集扩充字考(五・完结)附扩充块新增字考". 知乎专栏 (in Chinese). Retrieved 2023-09-21.