A python library and script for changing brightness on Linux via acpi. Allows for easing animations too!
pip install acpibacklight
You can use the script acpi-ease-backlight
to adjust the backlight with
easing via acpi on your device. See acpi-ease-backlight --help
for options.
After installing via pip, use the script acpi-ease-backlight
. Here is how
you might use it:
$ acpi-ease-backlight -h # see help
...
$ acpi-ease-backlight show # show the current backlight value
4000
$ acpi-ease-backlight max # show the your display's max backlight value
4882
$ acpi-ease-backlight set 2000 # set the backlight to 2000, over the default
# duration of 0.25 seconds and using the default
# easing function 'easeOutCubic'
$ acpi-ease-backlight -d 1 -e easeInOutQuad set 3000
# set the backlight to 3000 over duration of
# 1 second, using the easing function 'easeInOutQuad'
$ acpi-ease-backlight -d 0.5 dec 1000
# decrease the current backlight value by
# 1000 over a duration of 0.5 seconds
Use the class acpibacklight.AcpiBacklightControl
for changing the backlight
level in various ways. AcpiBacklightControl
is designed to use python with
statements similarly to file objects and python's open
builtin:
from acpibacklight import AcpiBacklightControl
with AcpiBacklightControl() as ctrl:
# set the brightness without animating
ctrl.brightness = 2000
# get max brightness on this device
new_brightness = ctrl.max
# You can also use the animate function on the AcpiBacklightControl.
# See the docstring for kwargs
ctrl.animate(new_brightness, duration=0.75)
Alternatively, you can construct, then open, then close the
AcpiBacklightControl
:
ctrl = AcpiBacklightControl()
ctrl.open()
ctrl.animate(ctrl.brightness - 1000)
ctrl.close()
If you have multiple ACPI backlight devices, specify the name when constructing
the AcpiBacklightControl
. Otherwise, the default is the first device directory
found.
ctrl = AcpiBacklightControl(device_dir='intel_backlight')
You can pass an easing function to be used in animate()
by the easing_func
keyword arg. This package uses PyTweening
for its default animation and the CLI, so you can easily pass one of those:
import pytweening
ctrl.animate(2345, easing_func=pytweening.easeInOutBounce)
Finally, if you want to create and pass your own easing function, it should take one paramater (time) between 0 and 1, and return a value between 0 and 1. For instance, a linear easing function would look like:
def linear_easing(t):
# t is always in the range [0, 1]
return t
# ...
ctrl.animate(1234, easing_func=linear_easing)