grid.Bezier {gridBezier}

Draw a Bezier Spline

Description

Draw a Bezier curve or Bezier spline (multiple Bezier curves strung together).

Usage

grid.Bezier(...)
BezierGrob(x, y, default.units="npc",
           open=TRUE, stepFn=nSteps(100), gp=gpar(), name=NULL)

Arguments

x, y

Locations of control points. There should be four, or seven (or six if not open), or ten (or nine), etc. Locations can be numeric or grid "unit" objects.

default.units

The coordinate system to use if control point locations are just numeric.

open

Whether to reuse the first control point as the last control point. If closed, the shape may also be filled.

stepFn

A function to generate values of t at which the curve will be evaluated for drawing. The default is 100 equal-sized steps from 0 to 1. This function is called for each Bezier curve within the Bezier spline, with arguments x, y (the control points), and range (indicating the range of t to generate values for).

gp

A grid "gpar" object, as produced by gpar(), or NULL.

name

A name for the grob that is generated.

...

Arguments passed from grid.Bezier() to BezierGrob().

Details

This function will produce a nicer result than the grid.bezier function from grid (because the latter is just an approximation using X-splines). This function also supports Bezier splines.

Value

BezierGrob produces a "BezierGrob" object.

Author(s)

Paul Murrell

Examples

grid.Bezier(c(.2, .2, .8, .8), c(.2, .8, .8, .2))