Shade an RGB color

Shades an RBG color

col.shade(col, shade = 0.5)

Arguments

col	a vector of RGB color(s)
shade	numeric value between 0 and 1. Zero means no change and 1 results in black

Details

This function shades an RGB color and returns the shaded RGB color (with alpha channel added)

References

Ekstrom, CT (2011) The R Primer.

Examples

newcol <- col.shade("blue")