Re: screen-gamma not always effective?

[Philip Rooke]

Chong Yidong <address@hidden> writes:

> Does this patch fix the problem?
>

I am sorry for the very late reply.  Unfortunately this does not fix
the problem, although it does change it.

The basic issue still remains.  After changing the value of
screen-gamma the effect is only seen in those parts of the screen that
contain text, this being true for the main part of the screen and also
the mini-buffer and scroll-bars.

What has changed is that the I am now seeing the effect earlier or in
slightly odd ways.  Two examples:

- Starting Emacs as (the colours simply accentuate the effect on my
  laptop)

  $ emacs -q -fg white -bg darkblue

  On the background to the splash screen the Emacs logo and subsequent
  text is shown in the gamma corrected colour.  The portion of the
  screen after the end of the text is uncorrected.

  If I wait until the splash screen times out and the *scratch* buffer
  is displayed then the first couple of lines with the auto text is
  shown in the gamma corrected colours, the rest of the screen is
  uncorrected.

  What is strange (to me at least) is that before applying your patch
  the startup screen would show the Emacs logo in uncorrected colour,
  the text in corrected colour, and the rest of the screen in
  uncorrected colour.

- Before applying your patch, using a function like:
  
  (modify-all-frames-parameters '((screen-gamma . 1.0)))

  only affected newly created frames.  These new frames would only
  show text areas of the sceen in the correct colour (with non-text
  portions of the screen still in the non-corrected colour).

  Evaluating the above call with your patch applied will now affect the
  current frame but will still only change the colours of text, not
  blank areas of the screen.

Thanks anyway for your consideration of the problem.

Phil