FontMetrics
Maintained for binary compatibility and previous construction with its named values
Parameters
greatest extent above origin of any glyph bounding box, typically negative; deprecated with variable fonts
distance to reserve above baseline, typically negative
distance to reserve below baseline, typically positive
greatest extent below origin of any glyph bounding box, typically positive; deprecated with variable fonts
distance to add between lines, typically positive or zero
average character width, zero if unknown
maximum character width, zero if unknown
greatest extent to left of origin of any glyph bounding box, typically negative; deprecated with variable fonts
greatest extent to right of origin of any glyph bounding box, typically positive; deprecated with variable fonts
height of lower-case 'x', zero if unknown, typically negative
height of an upper-case letter, zero if unknown, typically negative
underline thickness
distance from baseline to top of stroke, typically positive
strikeout thickness
distance from baseline to bottom of stroke, typically negative