Fetches the specified math constant. For most constants, the value returned
is an HarfBuzz.position_t.
However, if the requested constant is #HB_OT_MATH_CONSTANT_SCRIPT_PERCENT_SCALE_DOWN,
#HB_OT_MATH_CONSTANT_SCRIPT_SCRIPT_PERCENT_SCALE_DOWN or
#HB_OT_MATH_CONSTANT_RADICAL_DEGREE_BOTTOM_RAISE_PERCENT, then the return value is
an integer between 0 and 100 representing that percentage.
Fetches the specified math constant. For most constants, the value returned is an HarfBuzz.position_t.
However, if the requested constant is #HB_OT_MATH_CONSTANT_SCRIPT_PERCENT_SCALE_DOWN, #HB_OT_MATH_CONSTANT_SCRIPT_SCRIPT_PERCENT_SCALE_DOWN or #HB_OT_MATH_CONSTANT_RADICAL_DEGREE_BOTTOM_RAISE_PERCENT, then the return value is an integer between 0 and 100 representing that percentage.