Adjusting pixel brightness value of an image

[glv]

Another related topic:

Get HSB-mode saturation of a color constructed in RGB

If I set colorMode(RGB) and create a color c, then get saturation(c), it always gives me the HSL-mode saturation number, which is different from the HSB-mode number. I can’t think of any way to get the HSB-mode saturation of an RGB color. I know the algorithm to do it, so I could write my own function, but if someone doesn’t know that, it doesn’t seem possible. Is there no function that can convert a color from any mode to any other mode?

:)