Currently the "aromatic ring" is drawn for aromatic ring structures regardless of their size. The patch introduces an option to limit that behaviour to rings below a certain size. I.e., if the RingGenerator is used and the option is set to 7, only six-membered rings and smaller are drawn in aromatized form.
Complementing that change, the distance factor of the inner bond element for double bonds should scale with the ring size. However, large rings shouldn't have their "inner bonds" (if double bond) too far removed from the sigma bond, there should be a maximum limit. Otherwise the inner bond elements would continue to wander towards the center of the ring structure with a growing ring size. In the current patch, a ring size of 6 (most frequent case) is seen as ideal and results in a ring size factor of 2.5 (the current default in CDK). Given those values the ring size factor can grow up to a ring size of 15 before it is cut off and this value set as default for larger structures.
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