The designator adornment allows notes on an adornment to refer to the adornment's attributes. Only available in an adornment's $OnAdd action and in no other contexts. This is similar to the 'agent' designator.
In this context, using parent would result in the value being taken from the parent of the current map view.
From v5.6.0, the use of 'adornment' has been expanded. In all other contexts than the above, the designator 'adornment' refers to the map view adornment(s) on which the current note rests. If the note overlaps two or more adornments, "adornment" designates the uppermost (front-most) adornment.
If the note overlaps no adornment, then "adornment" is bound to "this". For example, the rule
$Color=$Color(adornment)
will change the note's color to match the color of an adornment, but leaves the color unchanged if the note does not overlap an adornment. This latter usage, with an inherent 'if on adornment' switch makes for more flexible coding in maps.
