Brightness & colour temperature control for desktop PCs

[Mike Walsh]

(deleted - n/a)

[MochiMoppel]

Do you have a test pet that I could trial on Slacko 5.6? (I am not keen to add sct or yad). cheers!

Sorry, no pet, just a testscript. I haven't tested extensively since I don't need and use it. IIRC worked OK on my Slacko 5.6.
Uses gtkdialog and Xdialog.
Supports more than 1 attached monitor (e.g. Laptop/Docking station + external monitor)
Supports Up/Down keys
Exits when focus is reset to window or desktop

I tested with a traybutton in JWM. No icon, just a Unicode symbol:

Code: Select all

<TrayButton label="◑">exec:/usr/bin/mm_brightness_slider</TrayButton>

The script:

Code: Select all

#!/bin/bash
ALIVE=$(xrandr --verbose | tr "\n" "\x0" | sed '	#replace linefeeds with NULL characters, thus putting the whole output on a single line
s/\x0[A-Z]/\n&/g		#xrandr output is indented. Only 'Screen' and Monitors appear left aligned, i.e they follow immediately after a linefeed. This command adds a 'real' lf before them
s/\x0//g' | sed -r '	#remove all NULL characters and pipe to another sed in order to detect newly inserted LFs
/Brightness/!d			#remove all lines not containing Brightness (leaving only monitors set 'on')
')
MON=$(echo "$ALIVE" | awk '{print $1}')		#may produce more than 1 monitor
if [ $(echo "$MON" | wc -l) -gt 1 ];then	#if more than 1, ask!
	XLIST=
	for monitor in $MON ;do
	XLIST="$XLIST $monitor $monitor off" 
	done
	MON=$(Xdialog --title "Brightness" --under-mouse --stdout --no-tags --radiolist "Please select monitor" x 4 $XLIST)
	[ $? != 0 ] && exit
fi
BrCur=$(echo  "$ALIVE" | sed -nr "s/$MON.*Brightness[: ]*([0-9.]*).*/\1/p" )
BrMax=1
BrMin=0.1
export STARTTIME=$(date +%s%2N)	#work around for bug that immediately fires focus-out-event (= exit) when slider opened on a desktop with no windows 
echo -n '
<window  type-hint="6" margin="0" window_position="2">
	<vscale range-value="'$BrCur'" range-min="'$BrMin'" range-max="'$BrMax'" range-step="0.05" width-request="28" height-request="200" inverted="true">
		<variable>vSLIDER</variable>
		<action>xrandr --output "'$MON'" --brightness $vSLIDER</action> 
	</vscale>
	<action signal="focus-out-event" condition="command_is_true(N=$(date +%s%2N);[ $((N-STARTTIME)) -gt 150 ] && echo true)">exit:</action>
</window>'|gtkdialog  -s

[greengeek]

I tested with a traybutton in JWM. No icon, just a Unicode symbol:

Code: Select all

<TrayButton label="◑">exec:/usr/bin/mm_brightness_slider</TrayButton>

My slider seems to have lost it's bottom. Is that something peculiar with my setup?

[MochiMoppel]

Is that something peculiar with my setup?

Definitely. In a pristine Slacko 5.6. the whole slider would be displayed. Your screenshot looks very strange. IMO this can only happen when the selected screen resolution and the physical resolution of the monitor don't match or when the wm is buggy. A window manager should never ever open a window off screen. Which JWM version do you use?

[fabrice_035]

hey,

Not working for me

Code: Select all

(gtkdialog:5862): Gtk-CRITICAL **: IA__gtk_vscale_new_with_range: assertion 'step != 0.0' failed

(gtkdialog:5862): Gtk-CRITICAL **: IA__gtk_range_set_value: assertion 'GTK_IS_RANGE (range)' failed
**
ERROR:variables.c:189:variables_new_with_widget: assertion failed: (widget != NULL)
./add.sh: line 27:  5861 Done                    echo -n '
<window  type-hint="6" margin="0" window_position="2">
   <vscale range-value="'$BrCur'" range-min="'$BrMin'" range-max="'$BrMax'" range-step="0.05" width-request="28" height-request="200" inverted="true">
      <variable>vSLIDER</variable>
      <action>xrandr --output "'$MON'" --brightness $vSLIDER</action>
   </vscale>
   <action signal="focus-out-event" condition="command_is_true(N=$(date +%s%2N);[ $((N-STARTTIME)) -gt 150 ] && echo true)">exit:</action>
</window>'
      5862 Aborted                 | gtkdialog -s

I use that, my old tiny brightness control

Code: Select all

#!/bin/sh

# mini tool ! Easy change luminosity (mouse wheel)
#
# !!!! right for DELL XPS 1640 !!!!
#
#  14 fev 2016

b=`cat /sys/class/backlight/acpi_video0/actual_brightness `

lumi () {
if [ "$hs" -lt "0" ] ; then
hs="1"
echo $(( $b + $hs )) > /sys/class/backlight/acpi_video0/brightness
exit 0
fi
echo $(( $b + $hs )) > /sys/class/backlight/acpi_video0/brightness

}
export -f lumi

GTKDIALOG=gtkdialog

MAIN_DIALOG='
<window title="Lum" decorated="false"  skip_taskbar_hint="true"  window_position="2">
   
<vbox border-width="1" spacing="1">
   <hbox homogeneous="true">
<button use-stock="true" >  <input file stock="gtk-quit"></input> </button>
            <hscale space-expand="true" space-fill="true" range-min="1"  range-max="16" range-value="'$b'"  range-step="1" tooltip-text="change luminosity">
               <variable>hs</variable>
            <action>lumi</action>
            </hscale>
         </hbox>
         </vbox>
   <variable>MAIN_DIALOG</variable>
</window>
'
export MAIN_DIALOG
case $1 in
   -d | --dump) echo "$MAIN_DIALOG" ;;
   *) $GTKDIALOG  --program=MAIN_DIALOG ;;
esac 

[fredx181]

Not working for me

Code:

(gtkdialog:5862): Gtk-CRITICAL **: IA__gtk_vscale_new_with_range: assertion 'step != 0.0' failed

(gtkdialog:5862): Gtk-CRITICAL **: IA__gtk_range_set_value: assertion 'GTK_IS_RANGE (range)' failed
**
ERROR:variables.c:189:variables_new_with_widget: assertion failed: (widget != NULL)
......
......

Yes, tried on a few OS's with same gtkdialog version, on one I get the same errors as above, on the others it works fine.
Can't figure out what causes this.

Fred

[fabrice_035]

Must have range-step="1" , range-step=".01" crash

that it's ok :

Code: Select all

#!/bin/bash
ALIVE=$(xrandr --verbose | tr "\n" "\x0" | sed '   #replace linefeeds with NULL characters, thus putting the whole output on a single line
s/\x0[A-Z]/\n&/g      #xrandr output is indented. Only 'Screen' and Monitors appear left aligned, i.e they follow immediately after a linefeed. This command adds a 'real' lf before them
s/\x0//g' | sed -r '   #remove all NULL characters and pipe to another sed in order to detect newly inserted LFs
/Brightness/!d         #remove all lines not containing Brightness (leaving only monitors set 'on')
')
MON=$(echo "$ALIVE" | awk '{print $1}')      #may produce more than 1 monitor
if [ $(echo "$MON" | wc -l) -gt 1 ];then   #if more than 1, ask!
   XLIST=
   for monitor in $MON ;do
   XLIST="$XLIST $monitor $monitor off"
   done
   MON=$(Xdialog --title "Brightness" --under-mouse --stdout --no-tags --radiolist "Please select monitor" x 4 $XLIST)
   [ $? != 0 ] && exit
fi
BrCur=$(echo  "$ALIVE" | sed -nr "s/$MON.*Brightness[: ]*([0-9.]*).*/\1/p" )
BrMax=9
BrMin=1
export STARTTIME=$(date +%s%2N)   #work around for bug that immediately fires focus-out-event (= exit) when slider opened on a desktop with no windows
echo -n '
<window  type-hint="6" margin="0" window_position="2">
   <vscale range-value="'$BrCur'" range-min="'$BrMin'" range-max="'$BrMax'" range-step="1" width-request="28" height-request="200" inverted="true">
      <variable>vSLIDER</variable>
      <action>xrandr --output "'$MON'" --brightness "'0.'"$vSLIDER</action>
   </vscale>
   <action signal="focus-out-event" condition="command_is_true(N=$(date +%s%2N);[ $((N-STARTTIME)) -gt 150 ] && echo true)">exit:</action>
</window>'|gtkdialog  -s

[fredx181]

Must have range-step="1" , range-step=".01" crash

that it's ok :
....

That works, but then the maximum brightness to adjust is only 0.90

I think I found why it didn't work on one OS for me, I had that one set to Dutch language.
When I do e.g:

Code: Select all

LANG=C /usr/bin/mm_brightness_slider

Then the original script from MochiMoppel works fine for me.
EDIT: Or add on top of script:

Code: Select all

export LANG=C 

EDIT: Just to mention, to make it work, I changed first line "tr" command to "busybox tr" (Debian Stretch here)

Fred

[fabrice_035]

That works, but then the maximum brightness to adjust is only 0.90

Change BrMax=9

[fredx181]

That works, but then the maximum brightness to adjust is only 0.90

Change BrMax=9

I did just copy your code as is, so with the BrMax=9, but that value is not full brightness.
EDIT: I think I see what you mean now, change BrMax=9 to something else probably?
Tried changing to BrMax=10, but gives weird result.

[greengeek]

Which JWM version do you use?

Code: Select all

# jwm -v
JWM vgit-895 by Joe Wingbermuehle
compiled options: confirm fribidi icons jpeg nls png shape svg xft xinerama xpm xrender 
system configuration: /etc/system.jwmrc
# 

also:

Code: Select all

# xrandr
Screen 0: minimum 320 x 200, current 1280 x 800, maximum 8192 x 8192
LVDS1 connected 1280x800+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1280x800       60.0*+
   1024x768       60.0  
   800x600        60.3  
VGA1 disconnected (normal left inverted right x axis y axis)
DVI1 disconnected (normal left inverted right x axis y axis)
# 

[greengeek]

For a lot of the older 5-series Pups (570, 560, 571, Raring, Racy, etc.,) I've used a redshift binary of version 1.8 that I sourced from the Slackware repos via pkgs.org. It doesn't seem to need the addition of anything else;

Hi Mike, I would like to try your sct based utility so I installed your ScreenControl-v1.3-i686.pet but have no clue what to do after that.

Can you give me a quick tute that will help me get this running on Slacko 5.6 please?

The pet seems to include sct
- do I need to install redshift?
- how do i start this screen control utility?

Treat me like a numbskull and hold my hand

cheers!

[Mike Walsh]

For a lot of the older 5-series Pups (570, 560, 571, Raring, Racy, etc.,) I've used a redshift binary of version 1.8 that I sourced from the Slackware repos via pkgs.org. It doesn't seem to need the addition of anything else;

Hi Mike, I would like to try your sct based utility so I installed your ScreenControl-v1.3-i686.pet but have no clue what to do after that.

Can you give me a quick tute that will help me get this running on Slacko 5.6 please?

The pet seems to include sct
- do I need to install redshift?
- how do i start this screen control utility?

Treat me like a numbskull and hold my hand

cheers!

@ Ian:-

Hah. I had in fact already run you up a 'test' package for Screen Control v1.3 - reference the deleted post at the top of this page. Upon re-reading your previous post more closely, it appeared you didn't want to install either 'sct' or 'yad', and were in fact only interested in Mochi's script. So, I deleted the post as being 'n/a' (not applicable), in order to save on forum bandwidth.....something I feel we all of us (myself included here) tend to take way too much for granted.

---------------------------------

That being said, if you'd like to try it out, we need to ascertain one thing - whether you have YAD installed or not - which is needed for this to function correctly.

I know Slacko 5.6 doesn't come with YAD by default, so I have to assume you do not. If you enter this in the terminal:-

Code: Select all

yad --version

.....it'll soon tell us. If you do, you'll get something similar to the following:-

Code: Select all

0.40.0 (GTK+ 2.24.17)
sh-4.1#

.....otherwise, you'll get 'bash:command not found' returned.

----------------------------------------------------------

The 'trial' package I made up for you contains both 'sct' and 'yad'. This way, if you don't like it, simply uninstall, and they'll both be removed again. If you don't have YAD already on your system, then uninstall the ScreenControl .pet you've already got, and install this one instead:-

ScreenControl-v1.3-i686

Otherwise, continue with the version you do have.

Usage:-

You'll need to re-start 'X', first of all, since this is tray-based. That will place a black/yellow 'split-circle' icon in the tray.

Click on it. The 'Brightness' slider will appear. If you want to adjust this, set this first. I like to set this to around 88-90 for night-time use, but you'll find your own preference. To set the colour temperature with 'sct', click on the 'Colour Temperature' button. A second slider control will show, staggered above and to the left of the first. Adjust this to your personal preference (around 3600-4000 is a good starting point). Then click 'Done', and 'Done' again.

If, after this, you want to re-set the brightness, you'll find that it 'unsets' the 'colour temperature. Just bring the colour temp control up again, and 'nudge' it very slightly up or down.....that will restore it. (I never did figure out how to prevent it from doing this; later, I continued developing this using the redshift-cli script Fred wrote for it, so it kinda got forgotten about.)

Still works well enough, though.


Mike.

[MochiMoppel]

@greengeek: With JWM vgit-895 you are on your own. Your distro shipped with -835.
The fixed script below *may* solve your issue as it uses a different window type-hint, reducing the chance that the window manager misinterprets it.

@fabrice_035, fredx181: Many thanks for checking and fixing the script. I made the proposed changes and hope that it now works even for European users.

I also tried to make it consistent with the behavior of the retrovol slider. The retrovol slider keeps the button visible and uses the button as a toggle switch. By removing type-hint="6", which puts a window on top of any other window, even on top of the tray, I can prevent the "no open on empty desktop" bug mentioned in the comments. Interestingly the retrovol slider also shows a different behavior when opened on an empty desktop. The button opens/closes as expected, but the slider also closes when the mouse is removed from the slider (=leave-notify-event). Intended behavior or benign bug?

Unlike retrovol the brightness slider also closes on focus out. Personally I like the behavior of retrovol on an empty desktop but I think it may confuse users. This functionality - if desired - can easily be added to the existing focus-out instruction:

Code: Select all

	<action signal="focus-out-event">exit:</action> 
	<action signal="leave-notify-event">exit:</action> 

The (hopefully working) script now looks like this:

Code: Select all

#!/bin/bash
busybox pkill brightslider && exit
export LANG=C
ALIVE=$(xrandr --verbose | busybox tr "\n" "\x0" | sed '   #replace linefeeds with NULL characters, thus putting the whole output on a single line 
s/\x0[A-Z]/\n&/g      #xrandr output is indented. Only 'Screen' and Monitors appear left aligned, i.e they follow immediately after a linefeed. This command adds a 'real' lf before them 
s/\x0//g' | sed -r '   #remove all NULL characters and pipe to another sed in order to detect newly inserted LFs 
/Brightness/!d         #remove all lines not containing Brightness (leaving only monitors set 'on') 
') 
MON=$(echo "$ALIVE" | awk '{print $1}')		#may produce more than 1 monitor 
if [ $(echo "$MON" | wc -l) -gt 1 ];then	#if more than 1, ask! 
	XLIST= 
	for monitor in $MON ;do 
		XLIST="$XLIST $monitor $monitor off" 
	done 
	MON=$(Xdialog --title "Brightness" --under-mouse --stdout --no-tags --radiolist "Please select monitor" x 4 $XLIST) 
	[ $? != 0 ] && exit 
fi 
BrCur=$(echo  "$ALIVE" | sed -nr "s/$MON.*Brightness[: ]*([0-9.]*).*/\1/p" ) 
BrMax=1 
BrMin=0.1 
echo -n ' 
<window decorated="false" skip_taskbar_hint="true" margin="0" window_position="2"> 
	<vscale range-value="'$BrCur'" range-min="'$BrMin'" range-max="'$BrMax'" range-step="0.05" width-request="28" height-request="200" inverted="true"> 
		<variable>vSLIDER</variable> 
		<action>xrandr --output "'$MON'" --brightness $vSLIDER</action> 
	</vscale> 
	<action signal="focus-out-event">exit:</action> 
</window>'| exec -a brightslider gtkdialog  -s

@Mike Walsh: Sorry for the intrusion into your thread. I tried to respond to a request and didn't realize that such a small script can trigger so many issues. I just don't want to leave a mess

[greengeek]

With JWM vgit-895 you are on your own. Your distro shipped with -835.
The fixed script below *may* solve your issue as it uses a different window type-hint, reducing the chance that the window manager misinterprets it.

Thank you - unfortunately it did not change my symptom so I will need to review the reasons why I changed to jwm 895.

Also - the script does not work the same way my usual method does - the script seems to alter the gamma instead of backlight intensity. This gives an unnatural blue hue at lower intensities. Have I misunderstood what it is intended to do?

[MochiMoppel]

Also - the script does not work the same way my usual method does

And what is your usual method?

the script seems to alter the gamma instead of backlight intensity

The script alters brightness as sensed by xrandr which AFAIK is not the same as the physical backlight intensity of the monitor. A value of 1.0 seems to be relative of the physical backlight intensity.

The script always resets gamma to 1.0 for all 3 colors. So yes, your gamma will be altered if it was set to different values. Reducing brightness results in washed out colors and IMO increasing gamma would result in a more pleasant and sharp display but that's not for me to decide.

[greengeek]

install this one instead:-

ScreenControl-v1.3-i686

Usage:-

You'll need to re-start 'X', first of all, since this is tray-based. That will place a black/yellow 'split-circle' icon in the tray.

Thanks - this works very well. One question though - I can't figure out how you get the icon into the tray. I expected your pet to incorporate a pinstall.sh which modified .jwmrc-tray, but i see nothing like that.

I'd like to understand how the icon gets where it does...

[greengeek]

And what is your usual method?.

Well now that you ask, I realise that it uses xbacklight which I see Mike says is not a solution for desktops anyway.

(I had previously thought I was using a script to echo values to /sys/class/backlight/intel_backlight/brightness but that must have been a previous version)

Anyway, this is the relevant addition to my /root.jwmrc-tray:

Code: Select all

		<TrayButton popup="BacklightUP" icon="/usr/local/lib/X11/pixmaps/brightup24.png" border="true">exec:xbacklight +15</TrayButton>
		<TrayButton popup="BacklightDWN" icon="/usr/local/lib/X11/pixmaps/brightdwn24.png" border="true">exec:xbacklight -10</TrayButton>
		<TrayButton label="◑">exec:/usr/bin/mm_brightness_slider</TrayButton>
		<TrayButton popup="XVkbd" icon="/usr/local/lib/X11/pixmaps/kbd24.png" border="true">exec:xvkbdstart</TrayButton>
		<Pager/>

I don't understand why xbacklight would not work for desktops though.

EDIT : Turns out my original script did not use:
# echo [numeric_value] >sys/class/backlight/intel_backlight/brightness,
instead it used
# echo [numeric_value] > /sys/class/backlight/toshiba/brightness

I don't know why my system shows the "intel_backlight/brightness" as well as the "toshiba/brightness".

EDIT2 : It also shows:
/sys/class/backlight/acpi_video0/brightness

In order to determine valid values for [numeric_value] I use the following syntax to see what max brightness values are permissible:

Code: Select all

# cat /sys/class/backlight/toshiba/max_brightness
7
#

(The weird thing is that intel_backlight/brightness has a max permissible value of 1 but toshiba/brightness and acpi_video0/brightness have max permissible values of 7)

This max permissible value is not always the same on every system. I recall finding some useful scripts on the Arch forum for tailoring the [numeric_value] appropriately for each different system.

Found it:

Code: Select all

#https://bbs.archlinux.org/viewtopic.php?id=134972

#!/bin/bash

# base dir for backlight class
basedir="/sys/class/backlight/"

# get the backlight handler
handler=$basedir$(ls $basedir)"/"

# get current brightness
old_brightness=$(cat $handler"brightness")

# get max brightness
max_brightness=$(cat $handler"max_brightness")

# get current brightness %
old_brightness_p=$(( 100 * $old_brightness / $max_brightness ))

# calculate new brightness % 
new_brightness_p=$(($old_brightness_p $1))

# calculate new brightness value
new_brightness=$(( $max_brightness * $new_brightness_p / 100 ))

# set the new brightness value
sudo chmod 666 $handler"brightness"
echo $new_brightness > $handler"brightness"

[MochiMoppel]

Well now that you ask, I realise that it uses xbacklight which I see Mike says is not a solution for desktops anyway.

Shouldn't bother you as you seem to use a laptop. I've never used xbacklight so I don't know what is is capable of.

Since you complained about lost gamma: What are your gamma values? Does xbacklight retain those values? The funny thing with xrandr is that when only brightness is set, gamma is reset, and when only gamma is set, brightness is reset (to 1.0). I found that in order to keep the values, both brightness and gamma need to be set at the same time by a single xrandr command. Can be done but I'm not sure if anyone really needs it.

I'm also not sure if it is really necessary to directly change values in /sys/class/backlight. So far I assumed that xrandr would do this.

[greengeek]

What are your gamma values? .

To be honest I can't see how to display those at the moment. Will research more tomorrow.

EDIT : Just found the xgamma command:

Code: Select all

# xgamma
-> Red  1.000, Green  1.000, Blue  1.000
#

Based on your comments I just tried tweaking gamma via xrandr and can see the blue tint appear (found a comment saying that xrandr "brightness alterations only adjust the 3 gamma values equally rather than changing backlight")

What do you see if you enter:
xrandr --verbose

does it show any comments about "backlight"?

See the last post here:
https://unix.stackexchange.com/question ... brightness