PC‐GEOS (GeoWorks, BreadBox) fonts

The file starts with a FontFileInfo structure

00    FFI_signature       char * 4                ;"BSWF"
04    FFI_minorVer        byte                    ;minor version (0)
05    FFI_majorVer        byte                    ;major version (1)
06    FFI_headerSize      word                    ;size of font info section

followed by a FontInfo structure, without fileHandle.
The pointers in this structure are form the start of the structure; add 8 to get a pointer form the start of the file.

08    FI_fontID           word                    ;font ID
0a    FI_maker            word (0 for bitmap)     ;font manufacturer ID
0c    FI_family           FontAttrs (flags byte)  ;font family, etc.
0d    FI_faceName         char * 20               ;typeface name
21    FI_pointSizeTab     word (0x23)             ;start of table of point sizes
23    FI_pointSizeEnd     word                    ;end of bitmap faces
25    FI_outlineTab       word (0)                ;start of outline table
27    FI_outlineEnd       word (0)                ;end of outline faces

following 2 "only for DBCS_PCGEOS" which seems False:
29    FI_firstChar        char (0?)               ;first char included
2a    FI_lastChar         char (0?)               ;last char included


2b first point size table entry (at 0x23 + 8) (or at 2a? 0x23 +7?)
PointSizeEntry (10 bytes)

2a    PSE_style           TextStyle (byte flags; 0?)  ;style of face
2b    PSE_pointSize       sbyte                   ;integer point size <128
2c    PSE_dataSize        word                    ;size of data
2e    PSE_filePosLo       word                    ;position in file
30    PSE_filePosHi       word  (0?)              ;position in file

next entry at 0x34 so we need another word ?
32   unknown     word


the fileposhi and fileposlo appear to be relative to start of file

at the pointed-to location (dec 91, which is also pointsizeend + 6 ??) we have another table - unknown
FontBuf?

FontBuf         struct
    FB_dataSize         word            ; actual size of data (bytes)
    FB_maker            FontMaker (word)   ; manufacturer ID
    FB_avgwidth         WBFixed         ; average character width
    FB_maxwidth         WBFixed         ; width of widest character
    FB_heightAdjust     WBFixed         ; offset to top of font box
    FB_height           WBFixed         ; height of characters
    FB_accent           WBFixed         ; height of accent portion.
    FB_mean             WBFixed         ; top of lower case character boxes.
    FB_baseAdjust       WBFixed         ; offset to top of ascent
    FB_baselinePos      WBFixed         ; position of baseline from top of font
    FB_descent          WBFixed         ; maximum descent (from baseline)
    FB_extLeading       WBFixed         ; recommended external leading
                                        ;   line spacing = FB_height +
                                        ;                  FB_extLeading +
                                        ;                  FB_heightAdjust
    FB_kernCount        word            ; number of kerning pairs
    FB_kernPairPtr      nptr.KernPair   ; offset to kerning pair table
    FB_kernValuePtr     nptr.BBFixed    ; offset to kerning value table
if DBCS_PCGEOS
    FB_firstChar        Chars           ; first char in section
    FB_lastChar         Chars           ; last char in section
    FB_defaultChar      Chars           ; default character
else
    FB_firstChar        byte            ; first char defined
    FB_lastChar         byte            ; last char defined
    FB_defaultChar      byte            ; default character
endif
    FB_underPos         WBFixed         ; underline position (from baseline)
    FB_underThickness   WBFixed         ; underline thickness
    FB_strikePos        WBFixed         ; position of the strike-thru
    FB_aboveBox         WBFixed         ; maximum above font box
    FB_belowBox         WBFixed         ; maximum below font box
        ; Bounds are signed integers, in device coords, and are
        ; measured from the upper left of the font box where
        ; character drawing starts from.
    FB_minLSB           sword           ; minimum left side bearing
    FB_minTSB           sword           ; minimum top side bound
if not DBCS_PCGEOS
    FB_maxBSB           sword           ; maximum bottom side bound
    FB_maxRSB           sword           ; maximum right side bound
endif
    FB_pixHeight        word            ; height of font (invalid for rotation)
    FB_flags            FontBufFlags    ; special flags
    FB_heapCount        word            ; usage counter for this font
    FB_charTable        CharTableEntry <>
FontBuf ends



then we have a table of CharTableEntry (8 bytes) starting at hex a2 (maybe)

a2    CTE_dataOffset      nptr.CharData (word?)   ;Offset to data
    CTE_width           WBFixed   (word byte fixed-point?)  ;character width
    CTE_flags           CharTableFlags (byte flags?)  ;flags
    CTE_usage           word            ;LRU count

first pointer is 0747; first char is space at 07a2, a diff of dec 91
other pointers seem to make sense if we add 91 (the start of the FontBuf table)

character definitions then take the form of a CharData struct

07a2, 07a7    CD_pictureWidth     byte            ;width of picture data in bits
              CD_numRows          byte            ;number of rows of data
              CD_yoff             sbyte           ;(signed) offset to first row
              CD_xoff             sbyte           ;(signed) offset to first column
              CD_data             byte            ;data for character

(though 0 rows of data for space is interpreted as 1?? as the next char starts at +5))