;+
; NAME: rainbow
; PURPOSE:
; 	Return a vector of color indices, from fsc_color.
; NOTES:
; 	requires Dave Fanning's FSC_COLOR.pro
;
; 	Note that for output to file you need to call this AFTER you call
; 	psopen.
;
; INPUTS:
; KEYWORDS:
; 	n=n		how many colors do you want? this will repeat the rainbow enough
; 			times that you have at least n colors.
; 	/more	Return more colors (16 elements to the rainbow, versus
; 			the default 10)
; 	/pale	return a pastel rainbow instead of the usual vibrant colors.
; 	/dim	make any of the above color tables half as bright
; 	/light	inverse of dim: make any of the above twice as bright.
; OUTPUTS:
; 	a vector of color indices
;
; HISTORY:
; 	Began 2005-04-20 14:50:34 by Marshall Perrin 
;-

FUNCTION rainbow,n,more=more,number=number,pale=pale,redblue=redblue,$
	greenyellow=greenyellow, dim=dim, light=light

if keyword_set(n) then number=n

if keyword_set(redblue) then begin
	; a set of colors sliding from red to blue
	if ~(keyword_set(number)) then number = 20
	r = lindgen(number)*255/(number-1)
	b = reverse(r)
	colors = 256l^2*r+b
	return,colors
endif
if keyword_set(greenyellow) then begin
	; a set of colors sliding from red to blue
	if ~(keyword_set(number)) then number = 20
	r = lindgen(number)*255/(number-1)
	b = reverse(r)
	colors = 256l^2*r+b+256l*235
	return,colors
endif
		


; yellow on white is illegible, so avoid it. but on
; the screen it's ok. For postscript, use a dark-ish
; yellow instead
if !d.name eq "PS" then yellow="Peru" else yellow="Yellow"
; similarly, don't output white on postscript, use black instead
if !d.name eq "PS" then white="gray" else white="white"



 retval=  [     fsc_color('red'),    $
 				fsc_color('orange'), $
				fsc_color(yellow), $
				fsc_color('green'),  $
				fsc_color('forest green'), $
				fsc_color('cyan'),$   $
              	fsc_color('blue'),   $
				fsc_color('purple'), $
				fsc_color('magenta'), $
				fsc_color('gray'),$
				fsc_color(white)]

if keyword_set(more) then $
	retval =  [  $
	fsc_color('Red'),   $
	fsc_color('Orange Red'),   $
	fsc_color('Orange'),   $
	fsc_color(yellow),   $
	fsc_color('Green Yellow'),   $
	fsc_color('Green'),   $
	fsc_color('Dark Green'),   $
	fsc_color('Forest Green'),   $
	fsc_color('Cyan'),   $
	fsc_color('Blue'),   $
	fsc_color('Dodger Blue'),   $
	fsc_color('Purple'),   $
	fsc_color('Magenta'),   $
	fsc_color('Deep Pink'),   $
	fsc_color('Gray'),   $
	fsc_color(white)   $
	]


	if keyword_set(pale) then retval = $
		[ fsc_color('Pink'),$
		fsc_color('Khaki'),$
		fsc_color('Papaya'),$
		fsc_color('Light Cyan'),$
		fsc_color('Powder Blue'),$
		fsc_color('Honeydew'),$
		fsc_color('Lavender'),$
		fsc_color('Thistle')]


; return,  [     getcolor('red'),    getcolor('orange'), getcolor('yellow'), getcolor('green'),  getcolor('forest'), getcolor('cyan'),$   
;              getcolor('blue'),   getcolor('purple'), getcolor('magenta'), getcolor('gray'),   getcolor('white')]


if (keyword_set(number)) then begin
	rep = ceil(number*1.0/n_elements(retval))
	retval2 = retval
	for i=0L,rep do retval2 = [retval2,retval]
	return,retval2
endif
	

if keyword_set(dim) then begin 
	dim *=2 ; default dim is 2, but you can make it more if you want.
	; split into RGB
	B = retval mod 256l;
	G = (retval/256l) mod 256l
	R = (retval/(256l^2))
	retval= (r/dim)*256l^2+(g/dim)*256l+b/dim
end
if keyword_set(light) then begin 
	light *=2 ; default light is 2, but you can make it more if you want.
	; split into RGB, invert, divide, invert
	B = 255-(255-retval mod 256l)/light
	G = 255-(255-(retval/256l) mod 256l)/light
	R = 255-(255-(retval/(256l^2)))/light
	retval= r*256l^2+g*256l+b
end
	

	
return,retval




end