HFill

Property	Default	Meaning
points	[]	First edge of the filled region
boundary	0	Second edge as points, or an x baseline
direction	"horizontal"	Fill horizontally; may be overridden
space	Automatic	Use ambient data coordinates or local geometry

Fill a region between points and boundary, arrays of {x,y} records or [x,y] tuples. boundary may be a scalar baseline (default 0). Arrays must have matching lengths; a gap in either boundary splits the whole region.

direction defaults to vertical (horizontal for HFill). For vertical fills a scalar supplies y; for horizontal fills it supplies x. VFill is the vertical convenience. Defaults: pale blue fill, no stroke.

Numeric geometry follows Graph and participates in limits, including the baseline. SymFill samples function boundaries.