Atari ST series Technical Reference Manual page 341

dress may be at an offset of 76 bytes from the beginning of
the font header, in the dat__table variable.
+ 088 to +089
Width the font form in bytes (the sum of the pixel width of
all of the characters in the font, divided by 8).
+ 090 to +091
TextBlt special effects flag:
Bit
Number
0 Thickening (boldface)
1 Lightening
2 Skewing (italics)
3 Underline (not performed by TextBlt)
4 Outline
* Note that it is up to the application itself (or the VDI) to perform underlining.
+ 092 to +093
Mask used to lighten text (usually $5555). Can be obtained
from the skewmask variable of the font header.
+ 094 to +095
Mask used to italicize (usually $5555). Can be obtained from
the skewmask variable of the font header.
+ 096 to +097
Width by which to thicken text for boldface. Can be obtained
from the skewmask variable of the font header.
+ 098 to +099
Offset above baseline for italicizing (offset of 0, if skewing is
not used). Can be obtained from the skewmask variable of
the font header.
The Line A Variable Table
FWDITH
STYLE
Effect*
LITEMASK
SKEWMASK
WEIGHT
ROFF
( + $058 to +$059)
( + $05A to +$05B)
( + $05C to +$05D)
( + $05E to + $05F)
( + $060 to + $061)
(+$062 to +$063)
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