refine lua-script documentation

[ardour.git] / scripts / rawmidi.lua

diff --git a/scripts/rawmidi.lua b/scripts/rawmidi.lua
index 73e62ef2436ca4740b3438defa0cb7deefe9b0a9..3b1dfb1d689add192845ff47676a3e0d75828cb4 100644 (file)
--- a/scripts/rawmidi.lua
+++ b/scripts/rawmidi.lua
@@ -16,18 +16,24 @@ end
 function dsp_has_midi_input () return true end
 function dsp_has_midi_output () return true end
 
+-- "dsp_runmap" uses Ardour's internal processor API, eqivalent to
+-- 'connect_and_run()". There is no overhead (mapping, translating buffers).
+-- The lua implementation is responsible to map all the buffers directly.
 function dsp_runmap (bufs, in_map, out_map, n_samples, offset)
-       local ib = in_map:get(ARDOUR.DataType("midi"), 0); -- get id of input buffer
-       local ob = in_map:get(ARDOUR.DataType("midi"), 0); -- get id of output buffer
+       -- see http://manual.ardour.org/lua-scripting/class_reference/#ARDOUR:ChanMapping
+       local ib = in_map:get (ARDOUR.DataType ("midi"), 0); -- get index of the 1st mapped midi input buffer
+       local ob = in_map:get (ARDOUR.DataType ("midi"), 0); -- get index of the 1st mapped midi output buffer
        assert (ib ~= ARDOUR.ChanMapping.Invalid);
-       assert (ib == ob);  -- inplace, buffers are identical
+       assert (ib == ob);  -- require inplace, buffers are identical
 
-       local mb = bufs:get_midi (ib)
-       events = mb:table() -- copy event list into lua table
+       -- http://manual.ardour.org/lua-scripting/class_reference/#ARDOUR:MidiBuffer
+       local mb = bufs:get_midi (ib) -- get the mapped buffer
+       events = mb:table () -- copy event list into a lua table
 
+       -- iterate over all midi events
        for _,e in pairs (events) do
-               -- e is an http://ardourman/lua-scripting/class_reference/#Evoral:MidiEvent
-               --
+               -- e is-a http://manual.ardour.org/lua-scripting/class_reference/#Evoral:MidiEvent
+
                --print (e:channel())
        end
 end