> I've noticed another quirk, which is not really a big deal, but quirky
> nonetheless. For red, any value less than 9 is rendered black, for blue
> also, anything less than 9 is rendered black, and for green, anything less
> than 7 is rendered black. So you can get a darker green than you can red
> or blue. :) Maybe its just my display...
This is a consequence of the way Arena allocates colours on displays
with inadequate colours (ie 8bit or less). It would appear (from using
xcmap) that Arena allocates a 128 element colour rectangle: 4 red x 5
green x 4 blue, plus a 14 element grey ramp (16 elements including black
and white)
This is a good way to do it, because green contributes most to the
luminance information and we are less tolerant of big steps in luminance
than of big steps in chrominance.
I hope to analyse the perceptual spacing of different browsers colour
allocation strategies, but this will take a bit of time.
I hope I need not add that pages should not assign colours based on this
observed behaviour, but should specify the desired colours and let the
browser worry about how to represent them.
--
Chris Lilley, Technical Author
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