screen_rotate.rb

#!/usr/bin/ruby

WACOM_DEVICE_IDS = [12, 13]

ROTATIONS = %w{ NONE CCW HALF CW };
RANDR_VALUES = {
    'NONE' => 'normal',
    'CCW'  => 'left',
    'HALF' => 'inverted',
    'CW'   => 'right',
}

o = ARGV.shift

fail "Must specify one of #{ROTATIONS.join ','}" unless RANDR_VALUES.has_key? o

WACOM_DEVICE_IDS.each do |i|
    system "xsetwacom --set #{i} Rotate #{o}"
end

v = RANDR_VALUES[o]
system "xrandr -o #{v}"