R/makeTransparent.R

In manabusakamoto/evoldiver: What the package does (short line)

# Colour function
makeTransparent <- function(..., alpha=0.5) {
  if(alpha<0 | alpha>1) stop("alpha must be between 0 and 1")
  alpha <- floor(255*alpha) 
  newColor <- col2rgb(col=unlist(list(...)), alpha=FALSE)
  .makeTransparent <- function(col, alpha) {
    rgb(red=col[1], green=col[2], blue=col[3], alpha=alpha, maxColorValue=255)
  }
  newColor <- apply(newColor, 2, .makeTransparent, alpha=alpha)
  return(newColor) 
}