[ardour.git] / scripts / tomsloop.lua

ardour { ["type"] = "EditorAction", name = "Tom's Loop",
        license     = "MIT",
        author      = "Ardour Team",
        description = [[Bounce the loop-range of all non muted audio tracks, paste N times at playhead]]
}

-- for minimal configuration in dialogue
function action_params ()
        return { ["times"]   = { title = "Number of copies to add", default = "1"}, }
end

-- main method, every custom (i.e. non-ardour) method must be defined *inside* factory()
function factory (params) return function ()
        -- get options
        local p = params or {}
        local n_paste  = tonumber (p["times"] or 1)
        assert (n_paste > 0)

        local proc     = ARDOUR.LuaAPI.nil_proc () -- bounce w/o processing
        local itt      = ARDOUR.InterThreadInfo () -- bounce progress info (unused)

        local loop     = Session:locations ():auto_loop_location ()
        local playhead = Session:transport_frame ()

        -- make sure we have a loop, and the playhead (edit point) is after it
        if not loop then
                print_help();
                print ("Error: A Loop range must be set.")
                goto errorout
        end
        assert (loop:start () < loop:_end ())
        if loop:_end () >= playhead then
                print_help();
                print ("Error: The Playhead (paste point) needs to be after the loop.")
                goto errorout
        end

        -- prepare undo operation
        Session:begin_reversible_command ("Tom's Loop")
        local add_undo = false -- keep track if something has changed

        -- prefer solo'ed tracks
        local soloed_track_found = false
        for route in Session:get_tracks ():iter () do
                if route:soloed () then
                        soloed_track_found = true
                        break
                end
        end

        -- count regions that are bounced
        local n_regions_created = 0

        -- loop over all tracks in the session
        for route in Session:get_tracks ():iter () do
                if soloed_track_found then
                        -- skip not soloed tracks
                        if not route:soloed () then
                                goto continue
                        end
                end

                -- skip muted tracks (also applies to soloed + muted)
                if route:muted () then
                        goto continue
                end

                -- at this point the track is either soloed (if at least one track is soloed)
                -- or not muted (if no track is soloed)

                -- test if bouncing is possible
                local track = route:to_track ()
                if not track:bounceable (proc, false) then
                        goto continue
                end

                -- only audio tracks
                local playlist = track:playlist ()
                if playlist:data_type ():to_string () ~= "audio" then
                        goto continue
                end

                -- check if there is at least one unmuted region in the loop-range
                local reg_unmuted_count = 0
                for reg in playlist:regions_touched (loop:start (), loop:_end ()):iter () do
                        if not reg:muted() then
                                reg_unmuted_count = reg_unmuted_count + 1
                        end
                end

                if reg_unmuted_count < 1 then
                        goto continue
                end

                -- clear existing changes, prepare "diff" of state for undo
                playlist:to_stateful ():clear_changes ()

                -- do the actual work
                local region = track:bounce_range (loop:start (), loop:_end (), itt, proc, false)
                playlist:add_region (region, playhead, n_paste, false, 0)

                n_regions_created = n_regions_created + 1

                -- create a diff of the performed work, add it to the session's undo stack
                -- and check if it is not empty
                if not Session:add_stateful_diff_command (playlist:to_statefuldestructible ()):empty () then
                        add_undo = true
                end

                ::continue::
        end -- for all routes

        --advance playhead so it's just after the newly added regions
        if n_regions_created > 0 then
                Session:request_locate((playhead + loop:length() * n_paste),false)
        end

        -- all done, commit the combined Undo Operation
        if add_undo then
                -- the 'nil' Command here mean to use the collected diffs added above
                Session:commit_reversible_command (nil)
        else
                Session:abort_reversible_command ()
        end

        print ("bounced " .. n_regions_created .. " regions from loop range (" .. loop:length() ..  " frames) to playhead @ frame # " .. playhead)
        ::errorout::

-- when this script is called as an action, the output will be printed to the ardour log window
        function print_help()
                print("")
                print("---------------------------------------------------------------------")
                print("")
                print("Manual for \"Tom’s Loop\" Ardour Lua Script")
                print("")
                print("---------------------------------------------------------------------")
                print("---------------------------------------------------------------------")
                print("")
                print("Table of Contents")
                print("")
                print("1. The first test")
                print("2. Using mute and solo")
                print("3. Combining region clouds to a defined length")
                print("")
                print("Abstract: This script for Ardour (>=4.7 git) operates on the time")
                print("line. It allows to copy and combine specific portions within the loop")
                print("range to a later point on the time line with one single action")
                print("command. Everything that can be heard within the loop range is")
                print("considered for this process, namely non-muted regions on non-muted or")
                print("soloed tracks that are fully or partially inside the loop range. This")
                print("still sounds a bit abstract and will be more obvious with the")
                print("following example cases of use.")
                print("")
                print("For convenience, it’s recommended to bind the script to a keyboard")
                print("shortcut in order to quickly and easily access the \"Tom’s Loop\"")
                print("scripted action.")
                print("")
                print("-Open dialog \"Script Manager\" via menu Edit/Scripted Actions/Script")
                print("Manager")
                print("")
                print("-In tab \"Action Scripts\", select a line and press button \"Add/Set\"")
                print("")
                print("-In dialog \"Add Lua Action\", select \"Tom’s Loop\" from the drop down")
                print("menu and hit \"Add\"")
                print("")
                print("-In dialog \"Set Script Parameter\" just hit \"Add\" again")
                print("")
                print("-Close dialog \"Script Manager\"")
                print("")
                print("-Open dialog \"Bindings Editor\" via menu Window/Bindings Editor")
                print("")
                print("-In tab \"Editor\", expand \"Editor\", look for entry \"Tom’s loop\",")
                print("select it")
                print("")
                print("-Hit the keyboard shortcut to assign to this scripted action")
                print("")
                print("-Close dialog \"Key Bindings\"")
                print("")
                print("An alternative way to quickly access a scripted action is to enable")
                print("\"Action Script Button Visibility\" in \"Preferences/GUI\".")
                print("")
                print("---------------------------------------------------------------------")
                print("")
                print("1. The first test")
                print("")
                print("---------------------------------------------------------------------")
                print("")
                print("-Record a short sequence of audio input or import a wave file to a")
                print("track to get a region")
                print("")
                print("-Set a loop range inside that one region")
                print("")
                print("-Place the playhead after the loop range, possibly after the region,")
                print("non-rolling")
                print("")
                print("     _L====L_              V")
                print(" .____|____|____________.  |")
                print(" |R1__|_x__|____________|  |")
                print("")
                print("-Call \"Tom’s Loop\" via the previously created shortcut")
                print("")
                print("This results in a new region created at the playhead, with the length")
                print("of the loop range, containing audio of the original region. The")
                print("playhead moved to the end of this new region so that subsequent calls")
                print("to \"Tom’s Loop\" will result in a gap less series of regions.")
                print("")
                print("     _L====L_               --> V")
                print(" .____|____|____________.  .____|")
                print(" |R1__|_x__|____________|  |_x__|")
                print("")
                print("-Repeat calling \"Tom’s Loop\"")
                print("")
                print("This creates multiple copies of the loop range to line up one after")
                print("each other.")
                print("")
                print("     _L====L_                         --> V")
                print(" .____|____|____________.  .______________|")
                print(" |R1__|_x__|____________|  |_x__|_x__|_x__|")
                print("")
                print("-Set a different loop range and call \"Tom’s Loops\" again")
                print("")
                print("This will create a new region with the length of the new loop range")
                print("at the playhead.")
                print("")
                print("        _L=======L_                           --> V")
                print(" ._______|_______|______.  .______________________|")
                print(" |R1_____|_X_____|______|  |_x__|_x__|_x__|_X_____|")
                print("")
                print("By using \"Tom’s Loop\", the loop range - which can be easily set with")
                print("the handles - and the playhead it’s easy to create any sequence of")
                print("existing regions on the time line. This can be useful during the")
                print("arrangement phase where macro parts of the session are already")
                print("temporally layed out (in the loop) but not part of the final")
                print("arrangement yet. The process is non-destructive in a sense that the")
                print("existing regions layout in the current loop range won’t be touched or")
                print("replaced. The newly created regions are immediately visible on the")
                print("time line at the playhead position.")
                print("")
                print("")
                print("---------------------------------------------------------------------")
                print("")
                print("2. Using mute and solo")
                print("")
                print("---------------------------------------------------------------------")
                print("")
                print("Creating a sequence of regions like described above respects the")
                print("current mute and solo state of a track. Variations of the loop are")
                print("thus easy to create, further supporting the arrangement process.")
                print("")
                print("      _L====L_                         --> V")
                print("  .____|____|____________.  ._________.    |")
                print("  |R1__|_x__|____________|  |_x__|_x__|    |")
                print(" .__|R2|_y__|________|_.    |_y__|_________|")
                print(" |R3___|_z__|__________|         |_z__|_z__|")
                print("")
                print("")
                print("---------------------------------------------------------------------")
                print("")
                print("3. Combining region clouds to a defined length")
                print("")
                print("---------------------------------------------------------------------")
                print("")
                print("Multiple small regions say on a percussive track can be simplified")
                print("for later arrangement keeping the temporal relations by combining")
                print("them. Using \"Tom’s Loop\", the resulting regions will not only combine")
                print("the regions but also automatically extend or shrink the new regions")
                print("start and end point so that it is exactly of the wished length equal")
                print("to the loop range.")
                print("")
                print("_L======================L_                            --> V")
                print(" |   .____  .___.  _____|_______.  .______________________|")
                print(" |   |R1_|  |R2_|  |R3__|_______|  |______________________|")
                print("")
                print("See also: Lua Action Bounce+Replace Regions")
                print("")
        end -- print_help()
end -- end of anonymous action script function
end -- end of script factory