So I’m running an Acer C740 and I’m contemplating nuking my ChromeOS install and going with MATE. I really like it so far (have it installed to a USB).
The one thing I’m having a problem with is not being able to change the brightness without going to display setting and manually moving the slider.
I attempted the suggestion from the Ubuntu forum but to no avail. When I ran the program from the command line it said I didn’t have any hardware that had a backlight.
This will give you the current value for brightness, execute the command when at max brightness to know what the upper bound is.
Then once you know the max:
It occurs to me I only answered half the question.
#! /usr/bin/env python3
from subprocess import check_output, call
import argparse as ap
p = ap.ArgumentParser()
p.add_argument("direction", choices = ["+", "-"])
args = p.parse_args()
MAXBRIGHTNESS = 4000 # TODO: UPDATE THIS
STEP = MAXBRIGHTNESS / 10 # We want 10-percent increments
# Get current brightness value
current = check_output(
"pkexec mate-power-backlight-helper --get-brightness",
shell = True
)
# Update brightness value
current = float(current)
new = current
if args.direction == "+":
new += STEP
else:
new -= STEP
# Prevent (under/over)flow of new value
if new < 0:
new = 0
elif new > MAXBRIGHTNESS:
new = MAXBRIGHTNESS
# Update brightness
call(
"pkexec mate-power-backlight-helper --set-brightness " + str(int(new)),
shell = True
)
Save this code into a file, for instance in your home folder in a subfolder named "bin" and with the name "modbrightness.py" and edit inside the file the value for MAXBRIGHTNESS with the one you got previously. Note: you can also edit the STEP value if you feel a 10% increment is too little.
ouroumov@Bloc:~/Desktop$ ls ~/bin/modbrightness.py
/home/ouroumov/bin/modbrightness.py
ouroumov@Bloc:~/Desktop$
Make it executable using the command:
chmod +x ~/bin/modbrightness.py
Then go to keyboard shortcut preferences, and create a new shortcut (click add):
Note: you have to give the full path to the file including the "/home/your_username" part.
Thank you so much. As soon as I get back there I’ll give it a shot. You should totally send this upstream. Having a setting like this built into the DE would be a great addition for everone with a laptop.
I can’t believe you wrote a python script for me. That’s awesome. I’m learning python right now, so I’ll go through it line by line.
Lol, wait and see if it works before sending the cookies. ^^"
I’ve only tested the thing on my notebook.
Also please note that key combination CTRL+SHIFT++ I used will conflict with the “Zoom” shortcuts (like in the terminal) if you haven’t changed them, so I recommend you test using another combination.
So I changed MaxBrightness to 1000 from 4000 and now I have 10 increments. Here is the new code all written by ouroumov except for one character change:
#! /usr/bin/env python3
from subprocess import check_output, call
import argparse as ap
p = ap.ArgumentParser()
p.add_argument("direction", choices = ["+", "-"])
args = p.parse_args()
MAXBRIGHTNESS = 1000 # TODO: UPDATE THIS
STEP = MAXBRIGHTNESS / 10 # We want 10-percent increments
# Get current brightness value
current = check_output(
"pkexec mate-power-backlight-helper --get-brightness",
shell = True
)
# Update brightness value
current = float(current)
new = current
if args.direction == "+":
new += STEP
else:
new -= STEP
# Prevent (under/over)flow of new value
if new < 0:
new = 0
if new > MAXBRIGHTNESS:
new = MAXBRIGHTNESS
# Update brightness
call(
"pkexec mate-power-backlight-helper --set-brightness " + str(int(new)),
shell = True
)
It worked for me on ubuntu 18.04.
first install the package below
"mate-power-manager"
and proceed through the steps above.
My max brightness is 24000. So, make sure to change the max brightness value.
