Re: face colors on 256 colors terminals

[Dan Nicolaescu <dann@ics.uci.edu>]

"Eli Zaretskii" <eliz@gnu.org> writes:

  > > From: Dan Nicolaescu <dann@ics.uci.edu>
  > > Date: Wed, 06 Apr 2005 01:17:11 -0700
  > > 
[snip]
  > So I think the code in tty-colors.el is correct in this matter.  It
  > is, however, possible that the RGB values in color-name-rgb-alist were
  > incorrectly scaled from 8-bit variants, and need to be amended.

Agreed. The problem seems to be that tty-colors.el and color-name-rgb-alist
don't use the same of scaling. 
Do you want me to do check if rescaling the values in
color-name-rgb-alist gives good results?

  > 
  > > With this fixes the gray colors are mapped linearly, and so are the
  > > red1, blue1 and green1 colors (I checked the pixels in a screenshot).
  > 
  > Does ``this fix'' above refer to the changes in xterm.el alone, or to
  > the change in tty-colors.el as well?  I think we should make the
  > changes in xterm.el, but not in tty-colors.el.

By "fixes" I meant all the patches that I posted together, I did not
test them separately. (anyway the tty-colors.el patch should have zero
influence on what I saw because AFAICT that code path is only used
when creating a color from  #RGB, xterm-register-default-colors does
its own scaling).
If you don't want the tty-colors.el changes, then ene of the changes
in xterm.el, the one to xterm-rgb-convert-to-16bit is not good, it
should be 

        (lsh prim 8)
instead of:
  (logior prim (lsh prim 8))

The patch to xterm-standard-colors is obviously correct, so I could
check that in right now if you want. 

  > > Some standard face definitions use colors like "red" or "blue". They 
  > > should be changed "red1" (or "blue1")
  > 
  > Yes, I agree.  Can you post a patch to do that?

Will do. 

  > And thank _you_ for working on this.

Well that you too, our private mail discussion put me on the right
track to find out what the problem was. 

      --dan