How to get the list of glyphs vertical boundary values for a font?

[aminabedi68]

Hello
I have to decrease the ascender/descender values of a font somehow, but I don't know which glyphs have the most vertical top/buttom boundary values(there is a lot of glyphs and I'm looking for limiters to work on)... so is there a solution(fonttools script) to generate a list of glyphs vertical boundary values for a font?

[behdad]

Something like this?

from fontTools.ttLib import TTFont
from fontTools.pens.boundsPen import ControlBoundsPen as BoundsPen
import sys

f = TTFont(sys.argv[1])
glyphs = f.getGlyphSet()

ascender = f['hhea'].ascender
descender = f['hhea'].descender
print("font ascender {ascender} descender {descender}".format(ascender=ascender, descender=descender))
for glyphname in glyphs.keys():
  pen = BoundsPen(glyphs, True)
  glyphs[glyphname].draw(pen)
  if pen.bounds is None:
    continue
  (xMin, yMin, xMax, yMax) = pen.bounds
  if yMax > ascender:
    print("glyph {glyphname} yMax {yMax}".format(glyphname=glyphname, yMax=yMax))
  if yMin < descender:
    print("glyph {glyphname} yMin {yMin}".format(glyphname=glyphname, yMin=yMin))

[aminabedi68]

exactly! thank you @behdad this is perfect :)