Hey, thanks for the guide. I used method 1, rearranged so that it rotates clockwise.
Also wrote up a quick .desktop so I could put it into panel with an icon. You'd want to use the counterclockwise icon. Obviously, replace /path/to/script.
Code:
[Desktop Entry]
Categories=Application;
Comment[en_US]=Rotate the Screen
Comment=Rotate the Screen
Exec=/path/to/script/rotate
GenericName[en_US]=
GenericName=
Icon=/usr/share/icons/default.kde4/48x48/actions/object-rotate-right.png
MimeType=
Name[en_US]=Rotate
Name=Rotate
Path=
StartupNotify=true
Terminal=false
TerminalOptions=
Type=Application
X-DBUS-ServiceName=
X-DBUS-StartupType=
X-KDE-SubstituteUID=false
X-KDE-Username=
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