Appearance
Function: getHeuristicFontMetrics() ​
getHeuristicFontMetrics():
FontMetrics
Shared, font-independent FontMetrics used when a named face has no registered metrics but the deck has opted into measured fit (some other face is registered). Approximate but conservative — see heuristicCharRatio. A deck with no registered metrics at all does not engage measured fit, so this never fires there.