Thank you! I didn't realize there was a core image filter for this - it works out perfectly!

Yes I mean Bezier path. Basically when the user drags across the screen (with the apple pencil or other stylus for example) their hand will naturally shake a little bit, so the points being added to the curve are not perfectly straight. I was hoping for a way to move the points closer together regardless of their natural hand jitter. Other drawing apps typically call this a brush stabilizer.