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@JohnMertz
Last active Aug 27, 2020
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Automatically configure display layout and waybar for Sway
#!/usr/bin/perl
########################################################################
# Dependencies
########################################################################
#
# Depends on JSON::XS and Proc::ProcessTable
#
# Debian:
# apt install libjson-xs-perl libproc-processtable-perl
########################################################################
# Directories and Files
########################################################################
# Template is a normal config with the following in place of values:
# "output": __OUTPUT__
# "position": __POSITION__
# "width": __WIDTH__ (optional)
my $waybar_template = '/home/jpm/.screenlayout/waybar.template';
# Temporary directory to save generated waybar config(s)
my $waybar_temporary = '/tmp';
########################################################################
# Display Serials and Names
########################################################################
# Hash to match display Serial with a friendly name.
# You can get the serial from (quoted with *):
# $ swaymsg -t get_outputs
# Output eDP-1 'Unknown 0x057D *0x00000000*'
my %outputs = (
'0x00000101' => 'Sam',
'3CQ4342S6W' => 'HP-1',
'3CQ3310Q1Q' => 'HP-2',
'0x00000000' => 'LVDS'
);
########################################################################
# Display Configurations
########################################################################
# First-level key of hash is the name of each configuration
# Second-level keys are the display friendly-names, above
# Third-level are the actual settings for that display
my %configs = (
'detached' => {
'HP-1' => {
'on' => 0
},
'HP-2' => {
'on' => 0
},
'Sam' => {
'on' => 0
},
'LVDS' => {
'on' => 1,
'width' => 1920,
'height' => 1080,
'x' => 0,
'y' => 0,
'rotate' => 0,
'waybar' => 'bottom'
}
},
'stacked' => {
'Sam' => {
'on' => 1,
'width' => 1920,
'height' => 1080,
'x' => 960,
'y' => 0,
'rotate' => 0,
'waybar' => 'bottom'
},
'HP-1' => {
'on' => 1,
'width' => 1920,
'height' => 1080,
'x' => 0,
'y' => 1200,
'rotate' => 0,
'waybar' => 'top'
},
'HP-2' => {
'on' => 1,
'width' => 1920,
'height' => 1080,
'x' => 1920,
'y' => 1200,
'rotate' => 0,
'waybar' => 'top'
},
'LVDS' => {
'on' => 0
}
},
'sidebyside' => {
'HP-1' => {
'on' => 1,
'width' => 1080,
'height' => 1920,
'x' => 0,
'y' => 225,
'rotate' => 270,
'waybar' => 'top'
},
'Sam' => {
'on' => 1,
'width' => 1200,
'height' => 1920,
'x' => 1080,
'y' => 0,
'rotate' => 90,
'waybar' => 'top'
},
'HP-2' => {
'on' => 1,
'width' => 1080,
'height' => 1920,
'x' => 2280,
'y' => 225,
'rotate' => 90,
'waybar' => 'top'
},
'LVDS' => {
'on' => 0,
}
}
);
########################################################################
# Program (do not edit below)
########################################################################
use strict;
use warnings;
# Bail if zero or >1 args
my $config;
if (scalar(@ARGV) == 1) {
$config = shift;
} else {
die "Requires exactly one argument with supported config: " . join(', ', keys %configs) . "\n";
}
# Bail if requested config doesn't exist
unless (defined $configs{$config}) {
die "$config is not a defined configuration: " . join(', ', keys %configs) . "\n";
}
# Import and setup JSON object
use JSON::XS;
my $json = JSON::XS->new();
# Fetch connected displays
my $displays_raw = `swaymsg -t get_outputs --raw`;
my $displays = $json->decode($displays_raw);
# For each connected display, collect the desired settings for enabled
# displays and a list of displays to disable
my $on;
my @off;
for (my $i = 0; $i < scalar(@$displays); $i++) {
# If a display is found without any settings, print error and turn it off
unless (defined $configs{$config}{$outputs{$displays->[$i]->{serial}}}) {
print STDERR "Output $displays->[$i]->{name} ($displays->[$i]->{serial}) found without defined function. Disabling.\n";
push @off, $displays->[$i]->{name};
next;
}
# If display is enabled, copy all of the desired settings
if ($configs{$config}{$outputs{$displays->[$i]->{serial}}}{on}) {
$on->{$outputs{$displays->[$i]->{serial}}} = $configs{$config}{$outputs{$displays->[$i]->{serial}}};
$on->{$outputs{$displays->[$i]->{serial}}}{output} = $displays->[$i]->{name};
# Otherwise simply list it for disabling
} else {
push @off, $displays->[$i]->{name};
}
}
# Number of simultaneous outputs is limited by possible, so disabled displays first
foreach (@off) {
# Sway returns status as JSON
my $res_raw = `sway output $_ disable`;
my $res = $json->decode($res_raw)->[0];
# If failed, print to STDERR
unless ($res->{success}) {
print STDERR "Error ($res->{error}) in command 'sway output $_ disable'\n";
}
}
# Kill existing Waybars
require Proc::ProcessTable;
my $t = new Proc::ProcessTable;
foreach my $p ( @{ $t->table } ) {
my $cmndline = $p->{'cmndline'};
$cmndline =~ s/\s*$//g;
if ($cmndline =~ /^waybar.*/) {
if ($p->{'pid'} == $$) {
next;
} else {
$p->kill(9);
}
}
}
# Configure each enabled display
foreach my $out (keys %$on) {
# Build command, starting by enabling and powering on
my $cmd = "sway output $on->{$out}->{output} enable dpms on";
# If additional options are provided, add them to command
if (defined $on->{$out}->{rotate}) {
$cmd .= " transform $on->{$out}->{rotate}";
}
if (defined $on->{$out}->{x} && defined $on->{$out}->{y}) {
$cmd .= " position $on->{$out}->{x} $on->{$out}->{y}";
}
if (defined $on->{$out}->{width} && defined $on->{$out}->{height}) {
$cmd .= " mode $on->{$out}->{width}x$on->{$out}->{height}";
}
# Sway returns status as JSON
my $res_raw = `$cmd`;
my $res = $json->decode($res_raw)->[0];
# If failed, print to STDERR
unless ($res->{success}) {
print STDERR "Error ($res->{error}) in command '$cmd'\n";
}
# If waybar position is set, fork, generate config and execute it
if (defined $on->{$out}->{waybar}) {
my $pid = fork;
unless ($pid) {
open STDIN, '/dev/null';
open STDOUT, '>>/dev/null';
open STDERR, '>>/dev/null';
# Load in config template
my $waybar;
open (my $fh, '<', $waybar_template);
while (<$fh>) {
$waybar .= $_;
}
close $fh;
chomp $waybar;
# Replace basic preferences
$waybar =~ s/__OUTPUT__/"$on->{$out}->{output}"/;
$waybar =~ s/__POSITION__/"$on->{$out}->{waybar}"/;
if (defined $on->{$out}->{width}) {
$waybar =~ s/__WIDTH__/$on->{$out}->{width}/;
# If width is not set, comment that line out to use default
} else {
$waybar =~ s/([^\s]*\s*)__WIDTH__/\/\/ $1__WIDTH__/gg;
}
# Write config to a temporary file
my $tmp = $waybar_temporary . "/" . $on->{$out}->{output} . ".tmp";
open ($fh, '>', $tmp);
print $fh $waybar;
close $fh;
`nohup waybar --config=$tmp`;
print $tmp . "\n";
# Remove config
unlink $tmp;
}
}
}
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