Zugg Software :: View topic - [3.04] #cw not handling the white background

Posted: Sat Mar 07, 2009 9:05 pm

Using #CW blue,white should paint the foreground blue and the background white (compare #CW blue,ivory which works). Instead it uses black as the foreground, blue as the background and puts it in italics and blinking.

Import this and type 'go'

SubAdmin Joined: 18 Nov 2001 Posts: 5182

The reason is that "blue,white" uses the ansi color pallette. The ansi pallette only allows 8 colors for the background. If you count the names in the %color help white is 9; it is actually a shortcut for high,gray.

What you want is "blue,mxpwhite".

Posted: Sun Mar 08, 2009 3:53 pm

I was scouring the help trying to figure this out before I posted. There just wasn't a whole lot of information. I was looking at the help for #CW and #color among others, but I still came up dry. Where can I get more information on what you posted about white being a shortcut for high,gray?

Here's the help for %color which you mentioned, but how'd you get what you said from this help?

SubAdmin Joined: 18 Nov 2001 Posts: 5182

Count with me

Posted: Mon Mar 09, 2009 5:38 pm

In any case, ReedN still has a point that this doesn't work the way one would expect.

Vijilante is correct in his analysis. ANSI has 16 foreground colors, but only 8 background colors. "White" is the name for the foregound color #15. And this color index doesn't exist for a background color (which only has indexes 0-7). You'll see the same problem if you try to use "yellow", which is the name for foreground color #14.

There are only a couple of colors that have different foreground/background color names. As Vijilante said, I didn't ever create color shortcut names for all of the highlighted colors. But "White" was added to be different than gray/silver, and Yellow was added to be different than Olive because these were common color names. There was no standard naming at the time to distinguish between the dark red and the light red, or the dark green and light green, etc.

But in any case, and regardless of the history and implementation details, when someone says "#CW blue,white" or "#CW blue,yellow" then it really should just work, so I still consider this a bug and have added it to the bug list.

Posted: Mon Mar 09, 2009 6:00 pm

I think Vijilante's explanation just created more confusion for me regarding how this works. I understand that the name colors are referencing numerical colors, but what most confuses me is that if white doesn't map properly because there are only 8 possible colors, then how was I using 'ivory' and 'redbrick' without there being a mapping issue as well? Those esoteric colors somehow map back correctly to one of the 8 possible colors, but white doesn't?

Posted: Mon Mar 09, 2009 6:56 pm

When using color names, CMUD first checks the ANSI color names, and if a match isn't found, only then does it look for MXP color names. "ivory" and "redbrick" are MXP color names, so that causes #CW to generate MXP COLOR tags. But when the color name matches an ANSI color name (like red, blue, white, yellow, etc), then #CW is using the %ansi function to generate the colors. When you use "blue,white", the "white" matches ANSI color 15, and CMUD then tries to use a color index of 15 for the background color, but background colors only have 8 values. So it ends up with just blank, or uses an undefined color record.

The bug is that CMUD should only be matching the names of the first 8 ANSI colors when parsing the background color name. Using "white" or "yellow" for the background should trigger the MXP color mode, just like using "mxpwhite" already does.