From ac476880231e431da767c877c520e7cf144ad1f8 Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Tue, 14 May 2024 17:20:52 +0200
Subject: [PATCH] Add Lua plugin to map DM10-mkII Studio HiHat MIDI messages

---
 share/scripts/dm10studio.lua | 67 ++++++++++++++++++++++++++++++++++++
 1 file changed, 67 insertions(+)
 create mode 100644 share/scripts/dm10studio.lua

diff --git a/share/scripts/dm10studio.lua b/share/scripts/dm10studio.lua
new file mode 100644
index 0000000000..44c790031e
--- /dev/null
+++ b/share/scripts/dm10studio.lua
@@ -0,0 +1,67 @@
+ardour {
+    ["type"]    = "dsp",
+    name        = "DM10-mkII-Studio HiHat",
+    category    = "Utility",
+    license     = "MIT",
+    author      = "Ardour Community",
+    description = [[Map HiHat MIDI events depending on pedal CC. Specifically MIDI Note Number 8 is translated to 54,47,58 deending on CC-8.]]
+}
+
+function dsp_ioconfig ()
+    return { { midi_in = 1, midi_out = 1, audio_in = 0, audio_out = 0}, }
+end
+
+local hihat_note = -1
+local hihat_state = 0
+
+function dsp_run (_, _, n_samples)
+	assert (type(midiin) == "table")
+	assert (type(midiout) == "table")
+	local cnt = 1;
+
+	function tx_midi (time, data)
+		midiout[cnt] = {}
+		midiout[cnt]["time"] = time;
+		midiout[cnt]["data"] = data;
+		cnt = cnt + 1;
+	end
+
+	-- for each incoming midi event
+	for _,b in pairs (midiin) do
+		local t = b["time"] -- t = [ 1 .. n_samples ]
+		local d = b["data"] -- midi-event data
+		local event_type
+		if #d == 0 then event_type = -1 else event_type = d[1] >> 4 end
+
+		-- intercept CC message
+		if #d == 3 and event_type == 11 and d[2] == 8 then
+			hihat_state = d[3]
+		end
+
+		-- map Note event
+		if (#d == 3) and d[2] == 8 and event_type == 9 then
+			if     hihat_state < 42 then hihat_note = 54 -- Hihat_Closed
+			elseif hihat_state < 92 then hihat_note = 46 -- Hihat_Semi_Open
+			else                         hihat_note = 58 -- Hihat_Open
+			end
+			d[2] = hihat_note
+		end
+
+		-- translate aftertouch
+		if (#d == 3) and d[2] == 8 and event_type == 10 then
+			if (hihat_note > 0) then
+				d[2] = hihat_note
+			end
+		end
+
+		-- intercept note off
+		if (#d == 3) and d[2] == 8 and event_type == 8 then
+			if (hihat_note > 0) then
+				d[2] = hihat_note
+			end
+			--hihat_note = -1
+		end
+
+		tx_midi (t, d)
+	end
+end