Add example script to thin automation

scripts/s_thin_automation.lua

@@ -0,0 +1,47 @@
+ardour { ["type"] = "Snippet", name = "Thin Fader Automation" }
+
+-- --TODO--
+-- For a fully fledged EditorAction this script should
+-- offer a dropdown to select automation of all paramaters
+-- (not just the fader)
+-- see scripts/midi_cc_to_automation.lua and
+-- scripts/mixer_settings_store.lua
+-- Thinning Area should also be a numeric-entry or slider
+
+function factory () return function ()
+	-- get selected tracks
+	rl = Editor:get_selection ().tracks:routelist ()
+
+	-- prepare undo operation
+	Session:begin_reversible_command ("Thin Automation")
+	local add_undo = false -- keep track if something has changed
+
+	-- iterate over selected tracks
+	for r in rl:iter () do
+
+		-- get the Fader (aka "amp") control
+		local ac = r:amp ():gain_control () -- ARDOUR:AutomationControl
+		local al = ac:alist () -- ARDOUR:AutomationList
+
+		-- get state for undo
+		local before = al:get_state ()
+
+		-- remove dense events
+		al:thin (50) -- threashold of area below curve
+
+		-- save undo
+		local after = al:get_state ()
+		Session:add_command (al:memento_command (before, after))
+		add_undo = true
+
+		::out::
+	end
+
+	-- all done, commit the combined Undo Operation
+	if add_undo then
+		-- the 'nil' Commend here mean to use the collected diffs added above
+		Session:commit_reversible_command (nil)
+	else
+		Session:abort_reversible_command ()
+	end
+end end