Part of an element that I want to annotate obscures another (for example, two characters hugging). How should I place my polygons? Tuesday January 10th, 2017Thursday January 12th, 2017rst Polygons should not overlap. Annotating two overlapping characters can be solved by annotating as little as possible of the ‘invisible’ part of the object. Polygons can be concave as well as convex, so every shape and form is allowed here.