ArrowHead

Property	Default	Meaning
tip	[1, 0.5]	Tip position
angle	0	Screen-space direction in degrees, clockwise positive
head-size	px(9)	Head length
head-width	0.65	Full head width divided by its length
curve	0	Barb curvature from 0 (straight) to 1 (tangent to the shaft at the tip)
open	false	Draw stroked barbs instead of a closed head
barb	"both"	Draw both barbs, or only "left" / "right" relative to the arrow's direction
space	Automatic	Use ambient data coordinates or local geometry

A standalone head at tip, with a screen-space angle in degrees (positive clockwise). head-size defaults to px(9), head-width to 0.65. open draws two stroked barbs; a closed head uses fill. curve bows both barbs toward the shaft while keeping the tip and the two rear endpoints fixed. It accepts a finite number from 0 to 1; 0.7 gives a LaTeX-like shape. Both open and filled heads support curved barbs.

barb="left" or barb="right" selects one side for harpoons. Left and right are relative to the direction of travel: a right-pointing arrow's left barb is above the shaft. A closed single-barbed head fills the half-head between the selected barb and the shaft. head-width still describes the full two-sided width.

On Arrow, the same shape and paint options use the head- scope: head-open, head-curve, head-barb, head-stroke, and so on. head-size and head-width keep their existing names. Head position and direction follow the arrow's route.

Point inputs accept {x,y} or [x,y]; see Point values.

Inside Graph, numeric geometry uses data coordinates; outside it, geometry uses local fractions/px/em. space="local" opts out of an ambient graph, and space="data" requires one. Pixel strokes keep their size.

Projected point inputs also accept named numeric records such as {theta, r} or {x, y, z}; GeoMap uses {lon, lat}. Every dimension reaches the projection. See Projections for units and visibility rules.