[ft-devel] GETINFO opcode extension

[Werner LEMBERG]

Here some more information on the extended functionality of GETINFO,
as provided by Greg Hitchcock from Microsoft -- apparently the first
change in the bytecode instruction set since 10 years or so.  Well,
the changes aren't really new because ClearType exists already for
some time, but I haven't seen those flags documented before.


    Werner

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GETINFO

arg bits   return bits   meaning

 0         0-7           value 37 is MS rasterizer 1.8, value 38 is MS
                         rasterizer 1.9 (the latter hasn't been
                         released yet I think)
1-5        8-12          unchanged
 6         13            set to 1 if ClearType is enabled, otherwise
                         zero (for MS rasterizer v.1.6+ or MS
                         rasterizer >= v.1.8)
 7         14            set to 1 if ClearType widths are compatible
                         with mono- and grayscale widths.  Zero if
                         the widths are the natural ClearType widths
                         (for MS rasterizer >= v.1.8)
 8         15            set to 1 if ClearType symmetrical smoothing
                         is being used (for MS rasterizer >= v.1.8)
 9         16            set to 1 if ClearType is processing the LCD
                         stripes in BGR order.  Otherwise zero,
                         indicating RGB order (for MS rasterizer >=
                         v.1.8)