# 凸包 > [Wiki](Home) ? \[\[API Reference\]\] ? \[\[Geometry\]\] ? **Hull Geom** [\#](Hull-Geom#hull) d3.geom.**hull**() [](http://bl.ocks.org/mbostock/4341699) Create a new hull layout with the default *x*- and *y*-accessors. [\#](Hull-Geom#_hull) **hull**(*vertices*) Returns the convex hull for the specified *vertices* array, using the current x- and y-coordinate accessors. The returned convex hull is represented as an array containing a subset of the input vertices, arranged in counterclockwise order (for consistency with [polygon.clip](Polygon-Geom#clip)). Assumes the *vertices* array is greater than three in length. If *vertices* is of length <= 3, returns \[\]. [\#](Hull-Geom#x) hull.**x**(\[*x*\]) If *x* is specified, sets the x-coordinate accessor. If *x* is not specified, returns the current x-coordinate accessor, which defaults to: ``` function(d) { return d[0]; } ``` [\#](Hull-Geom#y) hull.**y**(\[*y*\]) If *y* is specified, sets the y-coordinate accessor. If *y* is not specified, returns the current y-coordinate accessor, which defaults to: ``` function(d) { return d[1]; } ```