Re: [tlug] Color Codes

[Matt Gushee <mgushee@example.com>]

Stephen J. Turnbull wrote:
>>>>>>"Lyle" == Lyle Saxon <Lyle> writes:
> 
>     Lyle> These are the colors that show up the same on every computer
>     Lyle> no matter what (or so I've been told)."
> 
> There are no colors that show up the same on every computer no matter
> what; even black and white can be arbitrary.

What he said. I think whoever wrote that didn't quite understand the 
purpose of the "Web-safe palette." It was never supposed to look exactly 
the same on all displays, but it was supposed to give you a set of 
colors that could be directly rendered--i.e. without dithering--on *all 
8-bit displays.* The palette is unnecessary for 24- and 32-bit displays, 
and it doesn't work for most 15- and 16-bit displays.

So you probably don't need to worry about it if most of your visitors 
live in the "first world" or in East Asia, where most people have fairly 
modern hardware. I don't know for sure, but I would imagine there are a 
lot of people in, say, Africa and South America still using old boxes 
with 8-bit color.

> In practice, most sites use photos and the like; if you're going to do
> that, you'd have to work awfully hard to come up with a set of colors
> that make the photos look satisfactorily nice and fit into the subset
> of colors you can count on being available.

True. The big issue, though, was with computer graphics like logos and 
icons. If you use the wrong colors, dithering on 8-bit displays can make 
a decent-looking logo into an appalling, even unrecognizable, mess.

> For the record, what _is_ a possible worry is underpowered computers
> or people who are doing complex visuals (eg in an image or video
> editor).  In either case it's possible that excessive use of
> non-standard colors (basically, the PC-8 plus their bright versions,
> giving 16) will result in the display server running out of colors, in
> which case the browser makes do in a browser-specific way.

Isn't that an X-specific issue? Seems to me that on Windows and MacOS, 
colors are all shared among all applications. But I'm not an expert on 
this stuff either.

--
Matt Gushee
Englewood, CO, USA