Showing changes from revision #2 to #3:
Added | Removed | Changed
Size | Value |
---|---|
256 x4 | Hash table of offsets to first kern pair with this hash value |
4 | Offset of end of all pairs |
4 | Font Kern Flags (see below) |
? | Kern pair data (see below) |
The kern pair data is stored consecutively, in hash function order.
Standard Pair Format | |
---|---|
Size | Value |
256 x4 | Hash table of offsets to first kern pair with this hash value |
4 | First letter of kern pair |
4 | X offset (if flag bit 1 clear) |
4 | Y offset (if flag bit 2 clear) |
Compressed Pair Format | |
---|---|
Bits | Value |
0-7 | First letter of kern pair |
8-31 | X or y offset |
If bit 31 of the flags is set, the kern data is compressed by combining the first two (or only two) words.
Bit | Meaning when set |
---|---|
0 | No bounding boxes |
1 | No x offset |
2 | No y offset |
31 | Specify short kern pairs |
All other bits reserved |
Kerning information is found by hash table lookup, using the functions:
Value | Function |
---|---|
Hash table index | (first letter) EOR (second letter ROR 4) |
Second letter | (first letter EOR hash table index) ROR 4 |