>It also looks like it is displayed incomplete in the grid's column. On my computer I see all 3 values ok even for 255,255,0.

Here's the small update I have done as I need to have that in a browse.

CREATE CURSOR AAA(COULEUR I,COULEURTEXT C(6))

* prepare base (rainbow) colors
* note that we skip the 0 and 32 brightness to do not show RGB(0,0,0) and RGB(255,255,255
* in all 24 columns in the first row
for Hue = 1 to BaseColours 
   for Lum = 1 to Brightnesses - 1 
      nColor = HLStoRGB( (Hue-1)*(HLSMAX/BaseColours ), Lum*(HLSMAX/Brightnesses ),;
       HLSMAX-abs(Lum*(HLSMAX/Brightnesses)*2 - HLSMAX))
      aC[Lum, Hue] = nColor
      aN[Lum, Hue] = allt(str(nColor % 256)) + "," + ;
       allt(str(int(nColor/256) % 256)) + "," + allt(str(int(nColor/65536) % 256))
INSERT INTO AAA (COULEUR,COULEURTEXT) VALUES (aC[Lum, Hue],aN[Lum, Hue])
   endfor
endfor
* prepare other (shadow) colors
for Sat = BaseColours+1 to BaseColours + ShadowColours
   for Lum = 1 to Brightnesses - 1 
      nColor = HLStoRGB( (Sat-BaseColours-1)*(HLSMAX/ShadowColours ),;
       Lum*(HLSMAX/Brightnesses ), abs(Lum*(HLSMAX/Brightnesses )*2 - HLSMAX))
      aC[Lum, Sat] = nColor
      aN[Lum, Sat] = allt(str(nColor % 256)) + "," + ;
      allt(str(int(nColor/256) % 256)) + "," + allt(str(int(nColor/65536) % 256))
INSERT INTO AAA (COULEUR,COULEURTEXT) VALUES (aC[Lum, Hue],aN[Lum, Hue])
   endfor
endfor
* prepare greyscale colors. Note the difference - to show black and white colours we
* divide brightness by another way
for Lum = 1 to Brightnesses - 1 
   nColor = min((Lum-1) * (256/(Brightnesses-2)),255)
   nColor = RGB(nColor,nColor,nColor)
   aC[Lum, BaseColours+ShadowColours+1] = nColor
   aN[Lum, BaseColours+ShadowColours+1] = allt(str(nColor % 256)) + "," + ;
   allt(str(int(nColor/256) % 256)) + "," + allt(str(int(nColor/65536) % 256))
INSERT INTO AAA (COULEUR,COULEURTEXT) VALUES;
 (aC[Lum,  BaseColours+ShadowColours+1],aN[Lum, BaseColours+ShadowColours+1])
endfor

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