Inverting the colours of applications - Xwindows

This is a discussion on Inverting the colours of applications - Xwindows ; Hi, I have a medical condition that means I can't tolerate white backgrounds for long. So I configure all applications to put white or yellow text on a black background. Unfortunately some applications (most notably Acrobat Reader 5 for Linux) ...

+ Reply to Thread
Results 1 to 3 of 3

Thread: Inverting the colours of applications

  1. Inverting the colours of applications

    Hi,

    I have a medical condition that means I can't tolerate white
    backgrounds for long. So I configure all applications to
    put white or yellow text on a black background.

    Unfortunately some applications (most notably Acrobat Reader
    5 for Linux) cannot be configured in this way. So if
    possible I'd like to get the X server (XFree86), or some
    proxy, or a VNC server or client, or whatever, to intercept
    the application's graphics and invert all the colours. (It
    has to invert ALL the colours, including all the shades of
    grey, otherwise anti-aliasing becomes unreadable.)

    Is there any easy way to do this that doesn't involve
    reading the X protocol specs?

    Thanks, Silas

    --
    Silas S Brown, St John's College Cambridge UK http://www.cus.cam.ac.uk/~ssb22
    Replace nospam with ssb22 to reply by email

    "Before the quarrel has burst forth, take your leave" - Proverbs 17:14

  2. Re: Inverting the colours of applications

    In comp.windows.x, Silas S. Brown

    wrote
    on 02 Nov 2003 17:53:18 +0000
    <877k2i8xo1.fsf@ssb22.joh.cam.ac.uk>:
    > Hi,
    >
    > I have a medical condition that means I can't tolerate white
    > backgrounds for long. So I configure all applications to
    > put white or yellow text on a black background.
    >
    > Unfortunately some applications (most notably Acrobat Reader
    > 5 for Linux) cannot be configured in this way. So if
    > possible I'd like to get the X server (XFree86), or some
    > proxy, or a VNC server or client, or whatever, to intercept
    > the application's graphics and invert all the colours. (It
    > has to invert ALL the colours, including all the shades of
    > grey, otherwise anti-aliasing becomes unreadable.)
    >
    > Is there any easy way to do this that doesn't involve
    > reading the X protocol specs?
    >
    > Thanks, Silas
    >


    I can't say I've tried it, but you can attempt to modify rgb.txt.
    However, that only works if the program is looking for the color
    "white" (as opposed to using XWhitePixel()).

    I've coded something that opens a DirectColor window on
    my system (an ATI-based video chip) and then modifies the
    colormap; it does some very interesting stuff visually but
    unfortunately not what you specifically want, and it only
    works while the cursor's in the window of my program --
    which might be good enough for viewing purposes but causes
    certain difficulties when one wants to scroll, etc.

    --
    #191, ewill3@earthlink.net
    It's still legal to go .sigless.

  3. Re: Inverting the colours of applications

    nospam@cam.ac.uk (Silas S. Brown) writes:

    > Hi,
    >
    > I have a medical condition that means I can't tolerate white
    > backgrounds for long. So I configure all applications to
    > put white or yellow text on a black background.
    >
    > Unfortunately some applications (most notably Acrobat Reader
    > 5 for Linux) cannot be configured in this way. So if
    > possible I'd like to get the X server (XFree86), or some
    > proxy, or a VNC server or client, or whatever, to intercept
    > the application's graphics and invert all the colours. (It
    > has to invert ALL the colours, including all the shades of
    > grey, otherwise anti-aliasing becomes unreadable.)
    >
    > Is there any easy way to do this that doesn't involve
    > reading the X protocol specs?


    The easiest thing to do is use xpdf instead of AcroRead.
    xpdf accepts the "-rv" argument.

    The version of AcroRead I have, does have an x resources file
    but I was unable to find any resource that controls the document
    color. My guess is that you would need to run the PDF thru
    some kind of filter to get AcroRead to use different colors.
    You could try contracting Adobe. They have a support page.

+ Reply to Thread