I am creating a drawing app which is similar to the one here: https://www.raywenderlich.com/87899/make-simple-drawing-app-uikit-swift
but when I set the line drawing alpha <1, when 2 lines overlaps, the overlapping parts get darker, how can I make make the overlapping part not getting darker?
Please check the image here - when 2 drawing lines overlap, the color get darker, how can I make it to keep the same