Display a rectangle filled with an arbitrary color gradient
gradient.rect draws a rectangle consisting of nslices subrectangles of the colors in col or those returned by color.gradient if col is NULL. The rectangle is 'sliced' in the direction specified by gradient.
gradient.rect(xleft,ybottom,xright,ytop,reds,greens,blues,col=NULL,
nslices=50,gradient="x",border=par("fg"))xleft,ybottom,xright,ytop |
Positions of the relevant corners of the desired rectangle, as in rect. |
reds,greens,blues |
vectors of the values of the color components either as 0 to 1 or ,if any value is greater than 1, 0 to 255. |
col |
Vector of colors. If supplied, this takes precedence over reds, greens, blues and nslices will be set to its length. |
nslices |
The number of sub-rectangles that will be drawn. |
gradient |
whether the gradient should be horizontal (x) or vertical. |
border |
The color of the border around the rectangle (NA for none). |
the vector of hexadecimal color values from color.gradient or col.
Jim Lemon
# get an empty box
plot(0:10,type="n",axes=FALSE)
# run across the three primaries
gradient.rect(1,0,3,6,reds=c(1,0),
greens=c(seq(0,1,length=10),seq(1,0,length=10)),
blues=c(0,1),gradient="y")
# now a "danger gradient"
gradient.rect(4,0,6,6,c(seq(0,1,length=10),rep(1,10)),
c(rep(1,10),seq(1,0,length=10)),c(0,0),gradient="y")
# now just a smooth gradient across the bar
gradient.rect(7,0,9,6,col=smoothColors("red",38,"blue"),border=NA)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.