R/colorfunctions.R
col.shade.Rd
Shades an RBG color
col.shade(col, shade = 0.5)
a vector of RGB color(s)
numeric value between 0 and 1. Zero means no change and 1 results in black
This function shades an RGB color and returns the shaded RGB color (with alpha channel added)
Ekstrom, CT (2011) The R Primer.
Claus Ekstrom claus@rprimer.dk
newcol <- col.shade("blue")