update and cleanup lua example scripts

1 files changed, 23 insertions, 16 deletions

diff --git a/scripts/s_fader_automation.lua b/scripts/s_fader_automation.lua
index e1ee2876e4..aaac7adfe9 100644
--- a/scripts/s_fader_automation.lua
+++ b/scripts/s_fader_automation.lua
@@ -1,46 +1,53 @@
-ardour { ["type"] = "Snippet", name = "fader automation" }
+ardour { ["type"] = "Snippet", name = "Fader Automation" }
 
 function factory () return function ()
 	local playhead = Session:transport_frame ()
 	local samplerate = Session:nominal_frame_rate ()
 
 	-- get selected tracks
-	rl = Editor:get_selection().tracks:routelist()
+	rl = Editor:get_selection ().tracks:routelist ()
+
 	-- prepare undo operation
 	Session:begin_reversible_command ("Fancy Fade Out")
 	local add_undo = false -- keep track if something has changed
-	-- iterate over selected tracks
-	for r in rl:iter() do
-		local ac = r:amp():gain_control() -- ARDOUR:AutomationControl
-		local acl = ac:alist() -- ARDOUR:AutomationControlList (state, high-level)
-		local cl = acl:list()  -- Evoral:ControlList (actual events)
 
-		ac:set_automation_state(ARDOUR.AutoState.Touch)
+	-- iterate over selected tracks
+	for r in rl:iter () do
+		local ac = r:amp ():gain_control () -- ARDOUR:AutomationControl
+		local al = ac:alist () -- ARDOUR:AutomationList (state, high-level)
+		local cl = al:list ()  -- Evoral:ControlList (actual events)
 
-		if cl:isnil() then
+		if cl:isnil () then
 			goto out
 		end
 
+		-- set automation state to "Touch"
+		ac:set_automation_state (ARDOUR.AutoState.Touch)
+
 		-- query the value at the playhead position
-		local g = cl:eval(playhead)
+		local g = cl:eval (playhead)
 
 		-- get state for undo
-		local before = acl:get_state()
+		local before = al:get_state ()
 
 		-- delete all events after the playhead...
 		cl:truncate_end (playhead)
+
 		-- ...and generate some new ones.
 		for i=0,50 do
+			-- use a sqrt fade-out (the shape is recognizable, and otherwise
+			-- not be possible to achieve with existing ardour fade shapes)
 			cl:add (playhead + i * samplerate / 50,
-				 g * (1 - math.sqrt (i / 50)),
-				 false, true)
+			        g * (1 - math.sqrt (i / 50)),
+			        false, true)
 		end
+
 		-- remove dense events
-		cl:thin(20)
+		cl:thin (20)
 
 		-- save undo
-		local after = acl:get_state()
-		Session:add_command (acl:memento_command(before, after))
+		local after = al:get_state ()
+		Session:add_command (al:memento_command (before, after))
 		add_undo = true
 
 		::out::