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VNC with inverted colours
The following hack will do this on a Linux system. It relies on VNC (Virtual Network Computing) and we will be making a small modification to the VNC viewer.
Note: This works as-is only for Debian-based distributions. If your distribution is not Debian then you need to modify this.
First, download invert-vnc.diff
and save it as
Then paste the following into a root prompt: the lines are long):
apt-get --no-upgrade install xnest libjpeg62-dev \ xvncviewer vncserver vnc-common libvncauth0 dpkg-dev cd /tmp apt-get source xvncviewer cat invert-vnc.diff | patch vnc-*/vncviewer/desktop.cThen, if you are using Debian 3.0 aka Woody, paste in the following (ONLY if you are using Woody):
cd vnc-*/vncviewer gcc-2.95 -I ../include/ -I ../vncviewer/ \ -I ../Xvnc/lib/zlib $( echo *.c | sed -e 's/corre.c//' \ -e 's/hextile.c//' -e 's/rre.c//' \ -e 's/zlib.c//' -e 's/tight.c//') \ /usr/X11R6/lib/libXt.so.6.0 \ /usr/lib/libjpeg.so.62 \ /usr/lib/libvncauth.so.0 \ /usr/X11R6/lib/libXaw.so.7 \ /usr/lib/libz.so.1 mv a.out /usr/local/bin/invert-vncFor Debian versions later than 3.0, paste the following instead of the above:
cd vnc-* apt-get --no-upgrade install linux-kernel-headers ./configure && make && mv vncviewer/vncviewer \ /usr/local/bin/invert-vncFinally, paste in the following script. You might like to change the variables at the beginning, especially
Geometry. Security note: all local users will be able to interfere with your X display.
cat > /usr/local/bin/run-inverted <<'EOF' #!/bin/bash Geometry=640x480 VNCDisplay=98 XnestDisplay=99 Xvnc :$VNCDisplay -geometry $Geometry -ac \ -once -deferglyphs 16 -nolisten unix & vnc_server_pid=$! Xnest -geometry $Geometry -ac \ -nolisten tcp :$XnestDisplay & xnest_pid=$! sleep 3 DISPLAY=:$VNCDisplay xsetroot -solid white DISPLAY=:$VNCDisplay $* & application_pid=$! DISPLAY=:$XnestDisplay invert-vnc \ -encodings raw -fullscreen :$VNCDisplay & DISPLAY=:$VNCDisplay xset s off DISPLAY=:$XnestDisplay xset s off wait $application_pid kill $vnc_server_pid ; kill $xnest_pid EOF chmod +x /usr/local/bin/run-invertedIf you use a different keyboard layout (e.g. Dvorak) then you may need to add the appropriate
export DISPLAY=:$VNCDisplayfirst; do not send it to
:$XnestDisplayor the real display). This should go before the
setxkbmapis less likely to work than
The program is now ready for use. Use it like this (as an ordinary user, not root):
applicationis the command to run the application that you wish to use with inverted colours. (If you need a window manager, create a script that launches the window manager and the application and run that.)
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