# antipolygon: Fill the complement of a polygon In GEOmap: Topographic and Geologic Mapping

## Description

Fill a plot with a color outside the confines of a polygon.

## Usage

 `1` ```antipolygon(x, y, col = 0, corner=1, pct=.4) ```

## Arguments

 `x` x coordinates of polygon `y` y coordinates of polygon `col` Fill color `corner` Corner on the plot to connect to at the end: 1 = LowerLeft(default) ; 2:UpperLeft 3 = UpperRight; 4=LowerRight `pct` Decimal percent of usr coordinates to expand beyond the polygon

## Details

antipolygon uses par("usr") to determine the external bounds of plotting region. Corners are labels from bottom left counter-clockwise, 1-4.

## Value

Used for graphical side effect

## Note

If the figure is resized after plotting, filling may not appear correct.

## Author(s)

Jonathan M. Lees <jonathan.lees@unc.edu>

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18``` ```x = runif(100) y = runif(100) ######### some data points to plot: plot(x,y) ########### create polygon: pp =list(x=c(0.231,0.316,0.169,0.343,0.311,0.484,0.757, 0.555,0.800,0.563,0.427,0.412,0.203), y=c(0.774,0.622,0.401,0.386,0.138,0.312,0.200,0.459, 0.658,0.624,0.954,0.686,0.813)) polygon(pp) antipolygon(x=pp\$x, y=pp\$y,col='blue') #### where as this does not look so good plot(x,y) antipolygon(x=pp\$x, y=pp\$y,col='blue', corner=2) ```