Re: [ft] Suggestion/Inquiry: keeping metrics.horiAdvance for emboldened fixed-width fonts

[Werner LEMBERG]

>> Finally, the correct way to embolden glyphs without increasing the
>> advance width is to *move* the glyphs themselves a little to the
>> left after emboldening!  Otherwise it can happen that the very
>> right of emboldened glyph gets overwritten (or cut off) by the next
>> glyph.
>
> But then, that could cause overwriting/cutting off on the left.

This is much more unlikely.  A glyph's advance width normally looks
like this.

     +-----+====================+-----+
        ^            ^             ^
  left side bearing  |        right side bearing
                     |
             glyph's bbox width

The emboldening code increases all three values.

     +--------+==========================+--------+

If you squeeze this into the old advance width, you get this.

     +-------+========================+

As can be seen, the glyph gets cut off.  However, if you center the
new bbox width, chances are high that it works as expected.

     +--+==========================+--+


    Werner