I think more than half of what I need is in your example.
I tried running your script, but I probably made a mistake. When I launch it, I don’t see any effect on my midi track. Also, I can only run it once; I have to close my Ardour session and reopen it to run your lua script again.
I launched Ardour from the command line, and I don’t receive any messages.
Open the script in Ardour Menu > Window > Scripting, then add some print messages.
Select a MIDI region (with grab tool) and then Run the script in that window
Perhaps some strategic messages like:
diff --git a/share/scripts/brutalize_midi.lua b/share/scripts/brutalize_midi.lua
index 7a8e734431..0a461fbcc0 100644
--- a/share/scripts/brutalize_midi.lua
+++ b/share/scripts/brutalize_midi.lua
@@ -41,9 +41,11 @@ function factory () return function ()
-- iterate over all selected regions
local sel = Editor:get_selection ()
for r in sel.regions:regionlist ():iter () do
+ print ("Selected:", r:name())
local mr = r:to_midiregion ()
-- skip non MIDI regions
if mr:isnil () then goto continue end
+ print ("Found MIDI Region:", r:name())
-- get MIDI Model of the region
local mm = mr:midi_source(0):model ()
@@ -55,6 +57,7 @@ function factory () return function ()
-- note is-a https://manual.ardour.org/lua-scripting/class_reference/#Evoral:NotePtr
-- get current position ..
local old_pos = note:time ()
+ print ("Found MIDI Note at:", old_pos:get_beats ())
-- ..generate random offset..
local tickdiff = math.floor (rv['rand']() * max_distance);
I copied and pasted the script, with some additional print messages, in the script window:
---- this header is (only) required to save the script
-- ardour { ["type"] = "Snippet", name = "" }
-- function factory () return function () -- -- end end
function factory () return function ()
-- Ask user about max randomness to introduce
local dialog_options = {
{ type = "label", align="left", title = "Brutalize MIDI" },
{
type = "dropdown", key = "divisor", title="Max randomness to introduce:", values =
{
["8th note"] = 2,
["16th note"] = 4,
["16th triplett (1/24)"] = 6,
["32nd"] = 8,
["32nd triplett (1/48)"] = 12,
["64th"] = 16
},
default = "16th note"
},
{
type = "dropdown", key = "rand", title="Move Notes..", values =
{
["only forward in time"] = function () return math.random() end, -- 0 .. +1
["only backward in time"] = function () return math.random() - 2; end, -- -1 .. 0
["either way"] = function () return 2 * math.random() - 1; end -- -1 .. +1
},
default = "either way"
}
}
local rv = LuaDialog.Dialog ("Select Automation State", dialog_options):run()
if not rv then return end
-- calclate max distance in 'ticks'
local ticks_per_beat = Temporal.Beats (1, 0):to_ticks ();
local max_distance = ticks_per_beat / rv['divisor']
-- iterate over all selected regions
local sel = Editor:get_selection ()
for r in sel.regions:regionlist ():iter () do
print ("Selected:", r:name())
local mr = r:to_midiregion ()
-- skip non MIDI regions
if mr:isnil () then goto continue end
print ("Found MIDI Region:", r:name())
-- get MIDI Model of the region
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
-- get current position ..
local old_pos = note:time ()
print ("Found MIDI Note at:", old_pos:get_beats ())
-- ..generate random offset..
local tickdiff = math.floor (rv['rand']() * max_distance);
print (old_pos:get_beats (), old_pos:get_ticks (), tickdiff)
-- .. and calculate new position.
local new_pos = Temporal.Beats (old_pos:get_beats (), old_pos:get_ticks () + tickdiff)
-- now modify the note (but don't allow to move a note before the session start [1|1|0])
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
-- apply changes, and save undo
mm:apply_command (Session, midi_command)
::continue::
end
end end
I received this:
LuaException : [string "---- this header is (only) required to save t..."]:35: attempt to call a nil value (method 'to_ticks')
