Add Lua script to randomize MIDI note position

share/scripts/midi_brutalize.lua

@@ -0,0 +1,41 @@
+ardour { ["type"] = "EditorAction", name = "MIDI Brutalize",
+	license     = "MIT",
+	author      = "Ardour Team",
+	description = [[Randomize MIDI Note position (de-quantize).]]
+}
+
+function factory () return function ()
+local sel = Editor:get_selection ()
+-- iterate over all selected regions
+for r in sel.regions:regionlist ():iter () do
+	local mr = r:to_midiregion ()
+	if mr:isnil () then goto continue end
+
+	local ticks_per_beat = Temporal.Beats (1, 0):to_ticks ();
+	local max_shift = ticks_per_beat / 4.0
+
+	-- get MIDI Model
+	local mm = mr:midi_source(0):model ()
+	-- Prepare Undo command
+	local midi_command = mm:new_note_diff_command ("MIDI Note Brutalize")
+
+	-- Iterate over all notes of the MIDI region
+	for note in ARDOUR.LuaAPI.note_list (mm):iter () do
+		-- note is-a https://manual.ardour.org/lua-scripting/class_reference/#Evoral:NotePtr
+		local old_pos = note:time ()
+
+		-- shift +/- 1/16th note
+		local tickdiff = math.floor ((math.random() - 0.5) * max_shift)
+		--print (old_pos:get_beats (), old_pos:get_ticks (), tickdiff)
+
+		local new_pos = Temporal.Beats (old_pos:get_beats (), old_pos:get_ticks () + tickdiff)
+		if old_pos ~= new_pos and new_pos > Temporal.Beats (0, 0) then
+			local new_note = ARDOUR.LuaAPI.new_noteptr (note:channel (), new_pos, note:length (), note:note (), note:velocity ())
+			midi_command:remove (note)
+			midi_command:add (new_note)
+		end
+	end
+	mm:apply_command (Session, midi_command)
+	::continue::
+end
+end end