from tkinter import font
FONT_DEFAULT_SIZE = 9
FONT_DEFAULT_SIZE_PIXEL = -12
def get_font_scale_factor(font_name):
"""
Calculate the ratio between the system font and the default font, on which default sizes are based
:return the ratio between system font (currently used) and the default font
"""
font_size_system = font.nametofont(font_name).cget("size")
if font_size_system > 0:
# pt size
return font_size_system / FONT_DEFAULT_SIZE
else:
return font_size_system / FONT_DEFAULT_SIZE_PIXEL