I have a queastion regarding interpolation. I have a typeface with three masters. In symmetrical characters like the lowercase o, which is completely symmetrical in all masters, the instances are offset by 1 pt. Does anyone understand why this happens?
This is caused by rounding and can’t be avoided.
Ok I see. Why is that?
When interpolating points, each one is interpolated individually and will most likely land on fractional coordinates. On that point the distances are still equal. But the coordinates need to be rounded and then one might move a tiny bit to the left, the other to the right. Each point can move by less then 0.5 units.