From 3770929742496f61a8d488e581a8f7253ffb4e8b Mon Sep 17 00:00:00 2001
From: Vincent Bernat <vincent@bernat.ch>
Date: Tue, 2 Nov 2021 10:12:56 +0100
Subject: [PATCH] picom: use a wrapper script to template picom configuration
 file

---
 bin/picom-configure                 | 13 +++++++++++++
 dotfiles/picom.conf                 |  4 ++--
 dotfiles/systemd/picom.service      |  4 +++-
 dotfiles/systemd/xsettingsd.service |  3 ++-
 dotfiles/xsession                   |  1 -
 5 files changed, 20 insertions(+), 5 deletions(-)
 create mode 100755 bin/picom-configure

diff --git a/bin/picom-configure b/bin/picom-configure
new file mode 100755
index 0000000..a7fb270
--- /dev/null
+++ b/bin/picom-configure
@@ -0,0 +1,13 @@
+#!/bin/sh -e
+
+DPI=$(xrdb -query | sed -nE 's/^Xft\.dpi:\s*//p')
+POLYBAR_HEIGHT=$((20 * DPI / 96))
+
+# Configure picom
+cat ~/.config/i3/dotfiles/picom.conf \
+    | sed -e "s/@POLYBAR_HEIGHT@/$POLYBAR_HEIGHT/" \
+          > $XDG_RUNTIME_DIR/i3/picom.conf.new
+
+# Put new configuration file in place
+cmp $XDG_RUNTIME_DIR/i3/picom.conf.new $XDG_RUNTIME_DIR/i3/picom.conf 2> /dev/null || \
+    mv $XDG_RUNTIME_DIR/i3/picom.conf.new $XDG_RUNTIME_DIR/i3/picom.conf
diff --git a/dotfiles/picom.conf b/dotfiles/picom.conf
index 3752515..777da41 100644
--- a/dotfiles/picom.conf
+++ b/dotfiles/picom.conf
@@ -37,11 +37,11 @@ opacity-rule = [
 # Shadow and fading
 fade-in-step = 0.08;
 fade-out-step = 0.08;
-shadow-opacity = 0.3;
+shadow-opacity = 0.5;
 shadow-radius = 10;
 shadow-offset-x = -3;
 shadow-offset-y = -3;
-xinerama-shadow-crop = false;
+shadow-exclude-reg = "x@POLYBAR_HEIGHT@+0+0"
 wintypes:
 {
   normal        = { shadow = true; };
diff --git a/dotfiles/systemd/picom.service b/dotfiles/systemd/picom.service
index 853fa86..29babdd 100644
--- a/dotfiles/systemd/picom.service
+++ b/dotfiles/systemd/picom.service
@@ -3,5 +3,7 @@ Description=Compositor for X11
 PartOf=graphical-session.target
 
 [Service]
-ExecStart=/usr/bin/picom
+ExecStartPre=%h/.config/i3/bin/picom-configure
+ExecStart=/usr/bin/picom --config ${XDG_RUNTIME_DIR}/i3/picom.conf
+ExecReload=%h/.config/i3/bin/picom-configure
 Restart=on-failure
diff --git a/dotfiles/systemd/xsettingsd.service b/dotfiles/systemd/xsettingsd.service
index 57283e9..9f7fe2e 100644
--- a/dotfiles/systemd/xsettingsd.service
+++ b/dotfiles/systemd/xsettingsd.service
@@ -10,5 +10,6 @@ ExecReload=%h/.config/i3/bin/xsettingsd-setup
 ExecReload=/usr/bin/kill -HUP $MAINPID
 # Restart i3 (it uses Xft.dpi)
 ExecReload=-/usr/bin/i3-msg restart
-# Restart polybar (it uses an environment variable)
+# Restart polybar and reload picom (they use an environment variable)
 ExecReload=/bin/systemctl --user try-restart polybar.service
+ExecReload=/bin/systemctl --user try-reload picom.service
diff --git a/dotfiles/xsession b/dotfiles/xsession
index 29c9d7e..77c8141 100755
--- a/dotfiles/xsession
+++ b/dotfiles/xsession
@@ -31,7 +31,6 @@ gtk3.css     .config/gtk-3.0/gtk.css
 qt5ct.conf   .config/qt5ct/qt5ct.conf
 systemd      .config/systemd/user
 dunstrc      .config/dunst/dunstrc
-picom.conf   .config/picom.conf
 polybar.conf .config/polybar/config
 rofi.conf    .config/rofi/config.rasi
 fonts.conf   .config/fontconfig/fonts.conf