CE: color editor (manipulates ARGB or HSV color values)

ce(color, filter, [amount])

color: A valid ARGB or RGB color String (eg #FF663399)
filter: Filter (alpha opacity, sat saturation, lum luminance) or gradient end color (see examples)
amount: A value between 0 and 100, for alpha 0 is fully transparent, for saturation 0 means greyscale and for luminance 0 is black

Formula	Description
$ce(#FF0000, invert)$	Will invert RGB color
$ce(#FF0000, comp)$	Will return complementary color
$ce(#FF0000, contrast)$	Return either black or white depending on best contrast
$ce(#FF0000, alpha, 50)$	Will make a fully opaque red into 50% transparent
$ce(#FF0000, sat, 0)$	Will convert red color into Greyscale equivalent
$ce(#FF0000, lum, 50)$	Will set red luminance to 50
$ce(#FF0000, lum, a50)$	Will add 50 to red luminance (0 to 100)
$ce(#FF0000, alpha, r50)$	Will remove 50 from red alpha (0 to 255)
$ce(#FF0000, #FF0000, 50)$	Mix half red and half blue (50% gradient)