Release 10.1A: OpenEdge Development:
Internationalizing Applications

Convmap changes

The convmap files support supplementary characters in the DBCS-to-UTF-8 conversion (type 17). Any conversion using supplementary characters must use the Unicode compression option. Unicode compression is input as an increasing set of Unicode pairs of the form high value, low value, followed by 0, for a maximum of 5 ranges, with an additional 0 at the end.

The following excerpt from a conversion specification compresses the Unicode values from four ranges in plane 0 and one range in plane 8:

CONVERT SOURCE-NAME "SUPPLEMENTARY-CP" TARGET-NAME "UTF-8" TYPE "17" FIRST-CONSTANTS # single, 1st start, 2nd start, gap 0xFFFF 0 0x580 0x4ABF # ccount, umin, umax, index power, delta power, bad character 779 0x0 0x0FFD 6 6 0 # unicode compression 0x451 0xA7 0 0x266F 0x2000 0 0x33CD 0x3000 0 0xFA2D 0xF900 0 0x8FFE5 0x8FF00 0 0 # High range 0x00 0x00 0x81 0xFC # low range 0x40 0x7E 0x80 0xFC 0xFF 0xFE ENDCONSTANTS

Compression cannot occur over more than one plane. For example, this would not be supported:

0x451 0xA7 0 0x345EE 0x20000 0 0 0 0 0 0 0 0 0 0 0

The actual mappings appear in the -DATA section of the table, with the Unicode values expressed as the hex value of the UTF-32 codepoint:

FIRST-DATA 0x00D8 0x8FF98 0x00DF 0x8FF9F 0x8140 0x3000 0x8141 0x3001 0x8143 0x8FF0C 0x8144 0x8FF0E ENDTABLE