library("colorspace")
library("RColorBrewer")

hm <- matrix( c(rep(1,3), rep(10,3), rep(100,3)), nrow=3, ncol=3, byrow=TRUE)
hm

## modified pal function
pal <- function(col, border = NA, ...)
 {
 n <- length(col)
 plot(0, 0, type="n", xlim = c(0, 1), ylim = c(0, 1),
 axes = FALSE, xlab = "", ylab = "", ...)
 rect(0:(n-1)/n, .5, 1:n/n, 1, col = col, border = border)
 }

## replace quartz() with dev.new() or win.graph() on windows
quartz(); pal(rainbow_hcl(4))


## redefine without a box
lasagna<- function(X, col=palette, axes=F, ...){
  image(t(X)[,(nrow(X):1)], col=col, axes=axes, ...  )
##  box()
}


## lasagna() uses image(), but manipulates the matrix so the image
## rendered is that of just painting the elements of the matrix.
##palette <- rev(sequential_hcl(5, h=120, c = 80, power = 2.2))
##palette <- rainbow_hcl(5, start=20, end=310)
##palette <- brewer.pal(6, "PuOr")
##palette <- brewer.pal(5, "PuOr")[c(3,4,2,1,5)]
palette <- brewer.pal(11, "PuOr")[c(1,8,3,5,10)]

palette <- rainbow_hcl(4)
pal(palette)

## replace quartz() with dev.new() or win.graph() on windows
quartz(); image(hm)
quartz(); image(hm, col=rainbow_hcl(6))
quartz();lasagna(hm, col=palette)
quartz();lasagna(hm, col=brewer.pal(3, "PuOr"))