# cylindrect: Display an apparent cylinder In plotrix/plotrix: Various Plotting Functions

## Description

Display rectangles shaded to appear like cylinders.

## Usage

 `1` ``` cylindrect(xleft,ybottom,xright,ytop,col,border=NA,gradient="x",nslices=50) ```

## Arguments

 `xleft` The position of the left side of the rectangle(s). `ybottom` The position of the bottom of the rectangle(s). `xright` The position of the right side of the rectangle(s). `ytop` The position of the top side of the rectangle(s). `col` The base color(s) of the rectangles. `border` Whether to draw a border and what color. `gradient` Whether to vary the shading horizontally ("x" - the default) or vertically (anything but "x"). `nslices` The number of "slices" of color for shading.

## Details

cylindrect displays a rectangle filled with "slices" of color that simulate the appearance of a cylinder. The slices are calculated so that the base color appears at the right or bottom edge of the rectangle, becomes progressively lighter to a "highlight" at two thirds of the width or height and then darkens toward the base color again.

The appearance is of a cylinder lit from above and to the left of the viewer. The position of the apparent light source is hard coded into the function.

## Value

The base color(s) of the rectangle(s).

## Author(s)

Jim Lemon

 ```1 2 3 4 5``` ``` plot(0,xlim=c(0,5),ylim=c(0,5),main="Examples of pseudocylindrical rectangles", xlab="",ylab="",axes=FALSE,type="n") cylindrect(0,0,1,5,"red") cylindrect(rep(1,3),c(0,2,4),rep(4,3),c(1,3,5),"green",gradient="y") cylindrect(4,0,5,5,"#8844aa") ```