Changing note length via script in MIDI editor doesn't update fast enough

_Stevie_ · 07-20-2021, 06:29 AM

When using a script to shorten the MIDI note length (via GetSetAllEvts) and literally holding the action, the MIDI editor is not updating fast enough to reflect the changes. Only when I release the action, I see the current state of the note length.

Feature request: could have have the MIDI editor updating for scripts the same way as in the arrange?

1. My script action, notice the first resizing is visible for a split second, and then visual feedback ceases UNTIL, I release my shortcut key

2. The native REAPER action: updates perfectly, while holding the key:

3. My same script from 1., but now used in the arrange window: updates perfectly!

mpl · 07-20-2021, 07:45 AM

My Interactive Toolbar uses also GetSetAllEvt API. Works as fast as arrange. Seems there is a problem somewhere in your code.

_Stevie_ · 07-20-2021, 08:15 AM

Hey mpl, thanks will investigate!

EDIT: had a look, I was wrong, I'm using the MIDISetNote method for this one, that's why.

EDIT2_: I tried with my nudge notes script (that one definitely is based on SetAllEvts, with a similar outcome. First SetAllEvts and then "move notes one pixel". For the record, there are a LOT of notes in that project:

The less notes in the project, the faster the update of the notes via SetAllEvts. The native "move notes" action doesn't seem to care for how many notes there are in a project. It's always smooth.

_Stevie_ · 07-20-2021, 06:40 PM

Found the culprit: I have set the key repeat rate to maximum. Apparently, Reaper doesn't really like that and scripts get executed too frequently, when pressing and holding a key.

_Stevie_ · 07-21-2021, 12:09 PM

Investigating further. because with the current project I'm working on, I still have issues, even though I have reduced the key repeat rate.

Definitely not a big project:

Here's what it looks like when changing note lengths via my script:

Here's the code I'm using:

Code:

local function ChangeNoteLengthMIDIEditor(take)

    local got_all_ok, midi_string = reaper.MIDI_GetAllEvts(take, "") -- write MIDI events to midi_string, get all events okay
    if not got_all_ok then reaper.ShowMessageBox("Error while loading MIDI", "Error", 0) return(false) end -- if getting the MIDI data failed
    
    local table_events = {} -- initialize table, MIDI events will temporarily be stored in this table until they are concatenated into a string again
    local midi_len = #midi_string -- get string length
    local string_pos = 1 -- position in midi_string while parsing through events 
    local offset, flags, msg
    

        while string_pos < midi_len-12 do -- parse through all events in the MIDI string, one-by-one, excluding the final 12 bytes, which provides REAPER's All-notes-off end-of-take message
        offset, flags, msg, string_pos = string.unpack("i4Bs4", midi_string, string_pos) -- unpack MIDI-string on string_pos
        local status_byte = msg:byte(1)>>4 -- writing to a variable speeds up the comparison in the next if statement

        if #msg == 3
        and status_byte == 8 -- note-off
        and flags&1 == 1 -- only selected notes
        then
            table.insert(table_events, string.pack("i4Bs4", offset+new_length, flags, msg)) -- move the note on event by new_position
            table.insert(table_events, string.pack("i4Bs4", -new_length, 0, "")) -- put an empty event after the note on event, to maintain the distance
        else
            table.insert(table_events, string.pack("i4Bs4", offset, flags, msg)) -- re-pack MIDI string and write unchanged events
        end
    end
    reaper.MIDI_SetAllEvts(take, table.concat(table_events) .. midi_string:sub(-12))
    reaper.MIDI_Sort(take)
end

_Stevie_ · 09-22-2022, 07:47 AM

Summing this up, since today I found the culprit. It turns out that the issue is, that the MIDI Editor isn't refreshed fast / often enough. Spamming a key literally freezes the ME update, until you lift the key. I tested this on macOS and Windows, and apparently, only Windows is affected.

The only solution to solve this is to use a function from the JS API:

Code:

reaper.JS_Window_Update( windowHWND )

But to be honest, this is ridiculous. I have to use a 3rd party library in order to make MIDI scripts update fast enough, really?

I'm truly annoyed by the fact that I wasted so much time on something (coding, finding workarounds, finding the issue...), that should work out of the box!

vitalker · 09-22-2022, 08:15 AM

Quote:

Originally Posted by _Stevie_

Summing this up, since today I found the culprit. It turns out that the issue is, that the MIDI Editor isn't refreshed fast / often enough. Spamming a key literally freezes the ME update, until you lift the key. I tested this on macOS and Windows, and apparently, only Windows is affected.

The only solution to solve this is to use a function from the JS API:

Code:

reaper.JS_Window_Update( windowHWND )

But to be honest, this is ridiculous. I have to use a 3rd party library in order to make MIDI scripts update fast enough, really?

I'm truly annoyed by the fact that I wasted so much time on something (coding, finding workarounds, finding the issue...), that should work out of the box!

Maybe it's a bug and the devs aren't aware of it?