1 files changed, 72 insertions, 0 deletions
diff --git a/share/scripts/faders_to_trims.lua b/share/scripts/faders_to_trims.lua
new file mode 100644
index 0000000000..3fd62833f2
--- /dev/null
+++ b/share/scripts/faders_to_trims.lua
@@ -0,0 +1,72 @@
+ardour {
+	["type"]    = "EditorAction",
+	name        = "Faders to Trims",
+	license     = "MIT",
+	author      = "PSmith",
+	description = [[Add 'Trim' plugins to all tracks.  Move the fader value into the trim.]]
+}
+
+function action_params ()
+	return
+	{
+	}
+end
+
+
+function factory (params)
+	return function ()
+		-- loop over all tracks
+		for t in Session:get_tracks():iter() do
+			
+			fader_value = t:gain_control():get_value()
+			if fader_value == 1 then
+				goto skip
+			end
+			if t:gain_control():automation_state() ~= ARDOUR.AutoState.Off then
+				goto skip
+			end
+
+			-- TODO: skip MIDI tracks without or with a post-fader synth
+			-- (fader is MIDI-velocity)
+
+			v = math.log(fader_value, 10)
+			trim_gain = 20*v
+			fader_pos = 0
+			local proc;
+			local i = 0;
+			
+			repeat
+				-- find the fader proc
+				proc = t:nth_processor (i)
+				if (not proc:isnil() and proc:display_name () == "Fader") then
+					fader_pos = i
+				end
+				i = i + 1
+			until proc:isnil()
+			
+			-- apply the trim
+			trim = t:nth_processor (fader_pos+1)
+			if (not trim:isnil() and trim:display_name () == "a-Amplifier") then
+				--existing trim found; sum the trim and the fader gain, and set the trim to that value
+				cur_gain = ARDOUR.LuaAPI.get_processor_param (trim, 0)
+				ARDOUR.LuaAPI.set_processor_param (trim, 0, trim_gain+cur_gain)
+			else
+				--create a new Trim processor, and set its value to match the fader
+				local a = ARDOUR.LuaAPI.new_luaproc(Session, "a-Amplifier");
+				if (not a:isnil()) then
+					t:add_processor_by_index(a, fader_pos-1, nil, true)
+					ARDOUR.LuaAPI.set_processor_param (a, 0, trim_gain)
+					a = nil -- explicitly drop shared-ptr reference
+				end
+			end
+
+			--zero the fader gain
+			t:gain_control():set_value(1, PBD.GroupControlDisposition.NoGroup)
+
+			::skip::
+
+		end --foreach track
+
+	end  --function
+
+end --factory