Add example script to convert MIDI-CC to Plugin Automation

diff --git a/scripts/_midi_cc_to_automation.lua b/scripts/_midi_cc_to_automation.lua
new file mode 100644 (file)
index 0000000..2d97b2c
--- /dev/null
+++ b/scripts/_midi_cc_to_automation.lua
@@ -0,0 +1,47 @@
+ardour { ["type"] = "Snippet", name = "MIDI CC to Plugin Automation" }
+
+function factory () return function ()
+       -- target automation lane: a plugin parameter on a track
+       local tgt = Session:route_by_name('Audio') -- get track
+       assert (not tgt:isnil ())
+       -- get AutomationList, ControlList and ParameterDescriptor
+       -- of the first plugin's 2nd parameter
+       local al, _, pd = ARDOUR.LuaAPI.plugin_automation (tgt:nth_plugin (0), 1)
+
+       -- Source MIDI CC parameter
+       local midi_channel = 0 -- 0..15
+       local cc_param = 0x56
+
+       local add_undo = false
+       Session:begin_reversible_command ("CC to Automation")
+       local before = al:get_state()
+       al:clear_list ()
+
+       -- for all selected MIDI regions
+       local sel = Editor:get_selection ()
+       for r in sel.regions:regionlist ():iter () do
+               local mr = r:to_midiregion ()
+               if mr:isnil () then goto next end
+
+               local bfc = ARDOUR.DoubleBeatsFramesConverter (Session:tempo_map (), r:position ())
+               local ec = mr:control (Evoral.Parameter (ARDOUR.AutomationType.MidiCCAutomation, midi_channel, cc_param), false)
+               if ec:isnil () then goto next end
+               if ec:list ():events ():size() == 0 then goto next end
+
+               for av in ec:list ():events ():iter () do
+                       local val = pd.lower + (pd.upper - pd.lower) * av.value / 127
+                       al:add (bfc:to (av.when), val, false, true)
+                       add_undo = true
+               end
+               ::next::
+       end
+
+       -- save undo
+       if add_undo then
+               local after = al:get_state()
+               Session:add_command (al:memento_command(before, after))
+               Session:commit_reversible_command (nil)
+       else
+               Session:abort_reversible_command ()
+       end
+end end