For those font developers who are not aware, the official CMap resource repository for our public ROSes is the CMap Resources Forum.

The UTF-16 and UTF-32 CMap resources were introduced in August of 2001, beginning with Adobe-CNS1-4. Those for Adobe-Korea1-2 and Adobe-Japan2-0 followed in January of 2002, followed by those for Adobe-GB1-4 in June of the same year. The UTF-16 and UTF-32 CMap resources for Adobe-Japan1-5 were not released until November of 2002. From that point, the UCS-2 CMap resources were deprecated, and were no longer updated. Clients that used the UCS-2 CMap resources were encouraged to use the UTF-16 or UTF-32 ones instead. For OpenType font development, in terms of building the Unicode (Format 4 and 12) 'cmap' subtables, the UTF-32 CMap resources are recommended.

When the UTF-16 and UTF-32 CMap resources for Adobe-Japan1-5 were developed, the following mappings changed when compared to the now-deprecated UCS-2 versions:

MappingExplanation

U+007C → CID+99	Was CID+93; error; swapped with U+00A6; NOTE: CIDs 93 and 99 have the same widths in all Morisawa and Adobe fonts
U+007E → CID+100	Was CID+95; error; U+02DC and U+0303 map to CID+95
U+00A6 → CID+93	Was CID+99; error; swapped with U+007C; NOTE: CIDs 93 and 99 have the same widths in all Morisawa and Adobe fonts
U+0127 → CID+15816	Was CID+12092; primary is U+210F, and maps to CID+12092
U+01C0removed	Was CID+99; primary is U+007C, and maps to CID+99
U+0361 → CID+15845	Was CID+758; primary is U+2312, and maps to CID+758
U+045Bremoved	Was CID+12092; primary is U+210F, and maps to CID+12092
U+2018 → CID+98	Was CID+670; U+2018 is for Latin text, and CID+98 is better
U+2019 → CID+96	Was CID+671; U+2019 is for Latin text, and CID+96 is better
U+201C → CID+108	Was CID+672; U+201C is for Latin text, and CID+108 is better
U+201D → CID+122	Was CID+673; U+201D is for Latin text, and CID+122 is better
U+203E → CID+226	Was CID+325; should have been CID+226 from the beginning
U+20DD → CID+16328	Was CID+779; primary is U+25EF, and maps to CID+779
U+2195removed	Was CID+12215
U+2225 → CID+15489	Was CID+666; primary is U+2016, and maps to CID+666; CID+15489 better matches CID+15490, which maps from U+2226
U+223C → CID+100	Was CID+665; primary is U+301C, and maps to CID+665
U+229Dremoved	Was CID+12186; primary is U+2296, and maps to CID+12186
U+229E → CID+15906	Was CID+12190
U+22EEremoved	Was CID+7897; vertical variant of U+2026
U+22EFremoved	Was CID+668; primary is U+2026, and maps to CID+668
U+2300removed	Was CID+12184; primary is U+2205, and maps to CID+12184
U+244Aremoved	Was CID+12116; error
U+2612 → CID+16233	Was CID+12185; primary is U+22A0, and maps to CID+12185
U+2EAC → CID+19130	Was CID+2260; primary is U+793A, and maps to CID+2260; U+2F70 also maps to CID+2260
U+5002 → CID+20299	Was CID+13383; for JIS X 0213:2000 compatibility
U+51DE → CID+20300	Was CID+14352; for JIS X 0213:2000 compatibility
U+5307 → CID+20301	Was CID+8404; for JIS X 0213:2000 compatibility
U+5561 → CID+20308	Was CID+14393; for JIS X 0213:2000 compatibility
U+5BEC → CID+20302	Was CID+8436; for JIS X 0213:2000 compatibility
U+5DB2 → CID+15405	Was CID+15269; for JIS X 0213:2000 compatibility
U+5ECB → CID+15390	Was CID+14510; for JIS X 0213:2000 compatibility
U+661E → CID+20304	Was CID+8476; for JIS X 0213:2000 compatibility
U+6677 → CID+16889	Was CID+14609; for JIS X 0213:2000 compatibility
U+6801 → CID+14066	Was CID+8494; for JIS X 0213:2000 compatibility
U+69EA → CID+13329	Was CID+13679; for JIS X 0213:2000 compatibility
U+6C3A → CID+20309	Was CID+14690; for JIS X 0213:2000 compatibility
U+6FF9 → CID+15395	Was CID+14741; for JIS X 0213:2000 compatibility
U+704A → CID+20306	Was CID+14744; for JIS X 0213:2000 compatibility
U+71B3 → CID+15397	Was CID+14766; for JIS X 0213:2000 compatibility
U+7462 → CID+16977	Was CID+8561; for JIS X 0213:2000 compatibility
U+7626 → CID+13893	Was CID+7725; for JIS X 0213:2000 compatibility
U+7934 → CID+17014	Was CID+14904; for JIS X 0213:2000 compatibility
U+7A60 → CID+20310	Was CID+14926; for JIS X 0213:2000 compatibility
U+7D5C → CID+17041	Was CID+8592; for JIS X 0213:2000 compatibility
U+8803 → CID+20312	Was CID+15107; for JIS X 0213:2000 compatibility
U+8FC6 → CID+18759	Was CID+15185; for JIS X 0213:2000 compatibility
U+9365 → CID+17168	Was CID+15238; for JIS X 0213:2000 compatibility
U+95AB → CID+20313	Was CID+15258; for JIS X 0213:2000 compatibility
U+9755 → CID+20314	Was CID+8696; for JIS X 0213:2000 compatibility
U+9B2D → CID+17205	Was CID+13372; for JIS X 0213:2000 compatibility
U+9C6A → CID+19061	Was CID+15346; for JIS X 0213:2000 compatibility
U+F929 → CID+20305	Was CID+8489; for JIS X 0213:2000 compatibility
U+F9DC → CID+13393	Was CID+8686; for JIS X 0213:2000 compatibility
U+FA10 → CID+7746	Was CID+8422; for JIS X 0213:2000 compatibility
U+FA11 → CID+14290	Was CID+8443; for JIS X 0213:2000 compatibility
U+FA15 → CID+20307	Was CID+8542; for JIS X 0213:2000 compatibility
U+FA24 → CID+18760	Was CID+8632; for JIS X 0213:2000 compatibility

Since releasing the UTF-16 and UTF-32 CMap resources, the only changes to existing mappings were the following:

November of 2002: The UniGB-UTF8-H (CMapVersion=13.001), UniGB-UTF16-H (CMapVersion=1.001), and UniGB-UTF32-H (CMapVersion=1.001) CMap resources had the mappings for U+30F8 and U+30F9 swapped. This was a simple matter of error correction.

September of 2003: The UniJIS-UTF8-H (CMapVersion=13.002), UniJIS-UTF16-H (CMapVersion=1.002), UniJIS-UTF32-H (CMapVersion=1.002), and UniJISX0213-UTF32-H (CMapVersion=1.002) CMap resources had the U+02C0 → CID+15897 mapping removed, and the U+02C1 → CID+15897 mapping added. This was a simple matter of error correction.

November of 2003: The UniGB-UTF8-V (CMapVersion=13.001), UniGB-UTF16-V (CMapVersion=1.001), and UniGB-UTF32-V (CMapVersion=1.001) CMap resources had the U+2225 → CID+7708 mapping removed.

December of 2005: The UniJIS-UTF8-V (CMapVersion=13.002), UniJIS-UTF16-V (CMapVersion=1.002), UniJIS-UTF32-V (CMapVersion=1.002), and UniJISX0213-UTF32-V (CMapVersion=1.002) CMap resources had the U+303B → CID+12107 mapping removed.

January of 2007: The UniJIS2004-UTF8-H (CMapVersion=1.001), UniJIS2004-UTF16-H (CMapVersion=1.001), and UniJIS2004-UTF32-H (CMapVersion=1.001) CMap resources introduced the following changes to existing mappings: U+5906 → CID+21371 (was CID+17469), U+609E → CID+21558 (was CID+14541), U+66B5 → CID+21722 (was CID+17755), U+7152 → CID+21933 (was CID+14762), and U+9A4A → CID+22920 (was CID+15319). These changes were for JIS X 0213:2004 compatibility.

As you can see from the above list of changes to existing mappings, they have been done infrequently, with the last one being over five years ago. Our policy is to not change existing mappings unless it is absolutely necessary.

In terms of CMap resource updates, such as for additional mappings, they are usually triggered by new versions of Unicode (a previously unencoded glyph can now be encoded; for example, Unicode Version 6.1 introduced U+9FCC, which maps to Adobe-Japan1-6 CID+20156, and which triggered a CMap resource update) or the definition of a new Supplement.