add MidiByteArray::compare_n()

[ardour.git] / scripts / s_plugin_automation.lua

diff --git a/scripts/s_plugin_automation.lua b/scripts/s_plugin_automation.lua
index e69de6662a760f7b8500cfa3fb0a6dde0d35971a..56129ff7928d0d0a4286bf843634b5fb2a98d2b1 100644 (file)
--- a/scripts/s_plugin_automation.lua
+++ b/scripts/s_plugin_automation.lua
@@ -1,25 +1,33 @@
-ardour { ["type"] = "Snippet", name = "plugin automation2" }
+ardour { ["type"] = "Snippet", name = "Plugin automation" }
 
 function factory () return function ()
+       -- query playhead position and session sample-rate
        local playhead = Session:transport_frame ()
        local samplerate = Session:nominal_frame_rate ()
 
-       local r = Session:route_by_remote_id(3)
-       -- get AutomationControList, ControlList and ParameterDescriptor
-       local acl, cl, pd = ARDOUR.LuaAPI.plugin_automation (r:nth_plugin (0), 0)
+       -- get Track/Bus with RID 3
+       local r = Session:get_remote_nth_route(3)
+       -- make sure the track object exists
+       assert (not r:isnil ())
 
-       if not acl:isnil() then
+       -- get AutomationList, ControlList and ParameterDescriptor
+       -- of the first plugin's first parameter
+       -- see http://manual.ardour.org/lua-scripting/class_reference/#ARDOUR:LuaAPI
+       local al, cl, pd = ARDOUR.LuaAPI.plugin_automation (r:nth_plugin (0), 0)
+
+       if not al:isnil () then
                print ("Parameter Range", pd.lower, pd.upper)
-               print ("Current value", cl:eval(playhead))
+               print ("Current value", cl:eval (playhead))
 
                -- prepare undo operation
                Session:begin_reversible_command ("Automatix")
-               local before = acl:get_state()
+               -- remember current AutomationList state
+               local before = al:get_state()
 
                -- remove future automation
                cl:truncate_end (playhead)
 
-               -- add new data points after the playhead 1 sec min..max
+               -- add new data points after the playhead 1 sec, min..max
                -- without guard-points, but with initial (..., false, true)
                for i=0,10 do
                        cl:add (playhead + i * samplerate / 10,
@@ -28,8 +36,8 @@ function factory () return function ()
                end
 
                -- 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))
                Session:commit_reversible_command (nil)
        end
 end end