Make the blob nucleus more visible

[Isilkor]

compliments are colors that add up to white. organcolorRGB(x,y,z) is the inverse of blobcolorRGB(a,b,c) where (x,y,z) = (255-a, 255-b, 255-c)

so a blob of color 50, 200, 75 will have organs of color 205, 55, 180

and a black blob of 0,0,0 will have organs of color 255,255,255 aka white

The problem with just inverting the RGB color is that you'll end up with grey (127, 127, 127) if your input is grey (128,128,128). Instead, a better idea might be to rotate the color by 180° (60°, 120°, it doesn't really matter by how much exactly) in HSV and enforce a minimum saturation and value, so any input gets a distinguishable output.