pro show_hls,h,l,s

; v2 1/7/0 displays a checkerboard of different lightnesses based on the
;   same hue and saturation

nx=!d.x_size
ny=!d.y_size

tvlct,indgen(256),indgen(256),indgen(256)

hue=fltarr(nx,ny)
lig=fltarr(nx,ny)
sat=fltarr(nx,ny)

hue(*,*)=h
lig(*,*)=l
sat(*,*)=s

lig(0:nx/3,0:ny/3)=0.1
lig(nx/3:2*nx/3,0:ny/3)=0.2
lig(2*nx/3:nx-1,0:ny/3)=0.3
lig(0:nx/3,ny/3:2*ny/3)=0.4
lig(2*nx/3:nx-1,ny/3:2*ny/3)=0.6
lig(0:nx/3,2*ny/3:ny-1)=0.7
lig(nx/3:2*nx/3,2*ny/3:ny-1)=0.8
lig(2*nx/3:nx-1,2*ny/3:ny-1)=0.9
lig(nx/4:3*nx/4,ny/4:3*ny/4)=l

color_convert,hue,lig,sat,r,g,b,/hls_rgb
im_c=[[[r]],[[g]],[[b]]]
tv,im_c,true=3

xyouts,0.0,0.18,strcompress(string(fix(r(0,0))),/remove_all)+' '+$
  strcompress(string(fix(g(0,0))),/remove_all)+' '+$
  strcompress(string(fix(b(0,0))),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.0,0.14,strcompress(string(fix(r(0,0))),/remove_all)+' '+$
  strcompress(string(fix(g(0,0))),/remove_all)+' '+$
  strcompress(string(fix(b(0,0))),/remove_all),charsize=2.0,/normal,color=16777215
xyouts,0.0,0.10,strcompress(string(0.1),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.0,0.06,strcompress(string(0.1),/remove_all),charsize=2.0,/normal,color=16777215

xyouts,0.34,0.18,strcompress(string(fix(r(nx/3+1,0))),/remove_all)+' '+$
  strcompress(string(fix(g(nx/3+1,0))),/remove_all)+' '+$
  strcompress(string(fix(b(nx/3+1,0))),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.34,0.14,strcompress(string(fix(r(nx/3+1,0))),/remove_all)+' '+$
  strcompress(string(fix(g(nx/3+1,0))),/remove_all)+' '+$
  strcompress(string(fix(b(nx/3+1,0))),/remove_all),charsize=2.0,/normal,color=16777215
xyouts,0.38,0.10,strcompress(string(0.2),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.38,0.06,strcompress(string(0.2),/remove_all),charsize=2.0,/normal,color=16777215

xyouts,0.73,0.18,strcompress(string(fix(r(2*nx/3+1,0))),/remove_all)+' '+$
  strcompress(string(fix(g(2*nx/3+1,0))),/remove_all)+' '+$
  strcompress(string(fix(b(2*nx/3+1,0))),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.73,0.14,strcompress(string(fix(r(2*nx/3+1,0))),/remove_all)+' '+$
  strcompress(string(fix(g(2*nx/3+1,0))),/remove_all)+' '+$
  strcompress(string(fix(b(2*nx/3+1,0))),/remove_all),charsize=2.0,/normal,color=16777215
xyouts,0.73,0.10,strcompress(string(0.3),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.73,0.06,strcompress(string(0.3),/remove_all),charsize=2.0,/normal,color=16777215

xyouts,0.0,0.56,strcompress(string(fix(r(0,ny/2))),/remove_all)+' '+$
  strcompress(string(fix(g(0,ny/2))),/remove_all)+' '+$
  strcompress(string(fix(b(0,ny/2))),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.0,0.52,strcompress(string(fix(r(0,ny/2))),/remove_all)+' '+$
  strcompress(string(fix(g(0,ny/2))),/remove_all)+' '+$
  strcompress(string(fix(b(0,ny/2))),/remove_all),charsize=2.0,/normal,color=16777215
xyouts,0.0,0.48,strcompress(string(lig(0,ny/2)),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.0,0.44,strcompress(string(lig(0,ny/2)),/remove_all),charsize=2.0,/normal,color=16777215

xyouts,0.35,0.54,strcompress(string(fix(r(nx/2,ny/2))),/remove_all)+' '+$
  strcompress(string(fix(g(nx/2,ny/2))),/remove_all)+' '+$
  strcompress(string(fix(b(nx/2,ny/2))),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.35,0.50,strcompress(string(fix(r(nx/2,ny/2))),/remove_all)+' '+$
  strcompress(string(fix(g(nx/2,ny/2))),/remove_all)+' '+$
  strcompress(string(fix(b(nx/2,ny/2))),/remove_all),charsize=2.0,/normal,color=16777215
xyouts,0.22,0.34,strcompress(string(h),/remove_all)+' '+$
  strcompress(string(l),/remove_all)+' '+$
  strcompress(string(s),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.22,0.30,strcompress(string(h),/remove_all)+' '+$
  strcompress(string(l),/remove_all)+' '+$
  strcompress(string(s),/remove_all),charsize=2.0,/normal,color=16777215

xyouts,0.73,0.56,strcompress(string(fix(r(nx-1,ny/2))),/remove_all)+' '+$
  strcompress(string(fix(g(nx-1,ny/2))),/remove_all)+' '+$
  strcompress(string(fix(b(nx-1,ny/2))),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.73,0.52,strcompress(string(fix(r(nx-1,ny/2))),/remove_all)+' '+$
  strcompress(string(fix(g(nx-1,ny/2))),/remove_all)+' '+$
  strcompress(string(fix(b(nx-1,ny/2))),/remove_all),charsize=2.0,/normal,color=16777215
xyouts,0.73,0.48,strcompress(string(lig(nx-1,ny/2)),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.73,0.44,strcompress(string(lig(nx-1,ny/2)),/remove_all),charsize=2.0,/normal,color=16777215

xyouts,0.0,0.96,strcompress(string(fix(r(0,2*ny/3+1))),/remove_all)+' '+$
  strcompress(string(fix(g(0,2*ny/3+1))),/remove_all)+' '+$
  strcompress(string(fix(b(0,2*ny/3+1))),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.0,0.92,strcompress(string(fix(r(0,2*ny/3+1))),/remove_all)+' '+$
  strcompress(string(fix(g(0,2*ny/3+1))),/remove_all)+' '+$
  strcompress(string(fix(b(0,2*ny/3+1))),/remove_all),charsize=2.0,/normal,color=16777215
xyouts,0.0,0.88,strcompress(string(0.7),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.0,0.84,strcompress(string(0.7),/remove_all),charsize=2.0,/normal,color=16777215

xyouts,0.34,0.96,strcompress(string(fix(r(nx/2,ny-1))),/remove_all)+' '+$
  strcompress(string(fix(g(nx/2,ny-1))),/remove_all)+' '+$
  strcompress(string(fix(b(nx/2,ny-1))),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.34,0.92,strcompress(string(fix(r(nx/2,ny-1))),/remove_all)+' '+$
  strcompress(string(fix(g(nx/2,ny-1))),/remove_all)+' '+$
  strcompress(string(fix(b(nx/2,ny-1))),/remove_all),charsize=2.0,/normal,color=16777215
xyouts,0.38,0.88,strcompress(string(lig(nx/2,ny-1)),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.38,0.84,strcompress(string(lig(nx/2,ny-1)),/remove_all),charsize=2.0,/normal,color=16777215

xyouts,0.73,0.96,strcompress(string(fix(r(nx-1,ny-1))),/remove_all)+' '+$
  strcompress(string(fix(g(nx-1,ny-1))),/remove_all)+' '+$
  strcompress(string(fix(b(nx-1,ny-1))),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.73,0.92,strcompress(string(fix(r(nx-1,ny-1))),/remove_all)+' '+$
  strcompress(string(fix(g(nx-1,ny-1))),/remove_all)+' '+$
  strcompress(string(fix(b(nx-1,ny-1))),/remove_all),charsize=2.0,/normal,color=16777215
xyouts,0.73,0.88,strcompress(string(lig(nx-1,ny-1)),/remove_all),charsize=2.0,/normal,color=0
xyouts,0.73,0.84,strcompress(string(lig(nx-1,ny-1)),/remove_all),charsize=2.0,/normal,color=16777215

return
end