[ft] Nonsensical(?) values in font metrics.

[R0b0t1]

If I use face->bbox.xMax, face->bbox.yMax, face->max_advance_width, or
face->max_advance_height I receive a value which is approximately
twice as big as any rendered glyph, though halving it produces a value
slightly smaller than any rendered glyph. Is this an issue with the
font itself?

What is the best way to draw monospaced fonts? I was attempting to
calculate pen position assuming the glyphs could be laid out in a
grid. Based on the strange values in the font metrics and other
program's behavior it looks like glyphs are always drawn linewise,
respecting the advance of the last glyph, even if they are all the
same. Can anyone comment?

I can provide test code that should compile on most systems if it
would be helpful.

R0b0t1.