add base setup with dotter

config/mpv/scripts/mpv-i3-floating-centered.lua

@@ -0,0 +1,19 @@
+local utils = require 'mp.utils'
+
+local pid = utils.getpid()
+
+local function center_floating_mpv()
+   mpv_window_id = io.popen("xdotool search --pid " .. pid):read()
+
+   -- mpv can have a slight delay in launching a window, or be called without one at all
+   if mpv_window_id == nil then return end
+
+   floating = io.popen("xprop -id " .. mpv_window_id):read("*a")
+   if string.match(floating, "FLOATING") then
+      os.execute("i3-msg -q '[id=" .. mpv_window_id  .. "]' move position center")
+   end
+end
+
+mp.register_event("playback-restart", center_floating_mpv)
+-- mpv should still be centered when fullscreen is toggled
+mp.observe_property("fullscreen", "bool", center_floating_mpv)