Drum Patterns Randomizer

[aefa]

Hello everyone!
First off, I want to thank the community for all the help they provide at any given time.
After so many years of trial and error I've finished something that is useful to me and (though not perfect nor unique) I hope it would be useful to someone else.
I said earlier "many years" because every approach I would take led to a new challenge that needed more learning but, by the Grace of Heaven, I manage to build it (almost) from scratch in two days!! (self-standing ovation)

This is a simple midi vst to be used with a VSTi that supports pattern triggers, like Groove Agent or BFD.
It randomized the pattern variations with a single trigger to simulate a live player (BFD has this function but didn't work the way I wanted)

Would have been ideal to build the midi patterns in the vst instead of relying on other vsti but I can't wrap my head around that midilib for ruby

Any critic and/or improvement in functionality or visually would be welcome!

[aefa]

Hi! There is a bug that makes the note stick after a fill. Doesn't happen all the time but it happens. I'll repost when I figure it out (or someone does before me)

[aefa]

Tested With BFD3 in FL Studio! So far so good...
What I'm not too happy with, is the fact that picking random from an array (in ruby) usually brings up the same values Very noticeable with the fills.

[martinvicanek]

Unfortunately I know neither Groove Agent nor BFD, so I do not quite understand what exactly your device is supposed to do. Forgive my ignorance. I can see the work that has gone into building it, and it looks well organized and pretty.

It may be a stupid comment, but can't you create a new random sequence every time you need one instead of reading it from a (precomputed?) array? You could optionally use a time based seed, so there would never be any repetitions.

[tulamide]

Thanks Martin, for bringing my attention to this.

aefa, I looked at the Ruby part of your schematic.

1. MIDI Note Status 144
This is not just Note On. There is a mechanism called running status, in which midi messages are interpreted as belonging to the last status sent. This requires that a note off has to be sent to the last status. In case of 144 (normally Note On), this is an issue. So it was decided officially by the MIDI association, that 144 with a velocity of 0 is to be interpreted as 128 witch a velocity of 64. In other words, 144 + vel 0 = Note Off
You have to catch this exception (by checking if velocity is not 0, and executing the note off bits of your code, if it is), before running the rest of your code.

2. Midi message to array
Not really needed. The Midi class contains all methods to access all parts of a midi message. Instead of @inMidi = v.to_array and the following handling of the array, you can just call v.status, v.channel, v.data1 and v.data2

3. Event handling
Very severe issue! You don't check, which input caused the event method to run. But you access v. That means, if an incoming nPoolA caused the event method to trigger, v will not be a midi message, but an array. You then convert v.to_a, which leaves the array untouched and then perform midi interpretation on an array that has unrelated numbers (in case of nPoolA key numbers). Results are unpredictable. Worst case would be a crash of the other plugin or even the DAW. Best case would be just ignored messages.

4. Shuffling
While using shuffle is a legitimate tool for randomness, you implemented it a bit cumbersome. I won't comment on your question about same values showing up. This is most likely caused by point 3 of my list. Shuffle does shuffle everytime it is called. Of course, if there are only 2 elements in the array, the chance of the same order re-appearing is very high. And that's the case for any random algorithm in the world.
Another way, that might be a little faster in execution is not to shuffle the whole array, but to sample it. Arrays have the method sample, so myArray.sample will pick a random value from the array, without the work done by re-arranging a complete array. Instead of
return @notes.find_index(nP.shuffle.first)
try this
return @notes.find_index(nP.sample)

I hope this helps you.

[aefa]

Unfortunately I know neither Groove Agent nor BFD, so I do not quite understand what exactly your device is supposed to do. Forgive my ignorance. I can see the work that has gone into building it, and it looks well organized and pretty.

It may be a stupid comment, but can't you create a new random sequence every time you need one instead of reading it from a (precomputed?) array? You could optionally use a time based seed, so there would never be any repetitions.

There are never stupid comments! (I'm defending myself ) Idealy, I would have like to make it so I can make a pool of midi sequences, either manually or importing them from file, into parts (A,B,C,F) but I suck at programming! That is why I have to rely on vsti that implement triggered grooves. For example Addictive Drums has grooves but doesn't support triggering. My idea is to avoid making a variations of a pattern and hardcode them in the project. By randomizing the patterns it sounds more fluid (to my ears) and different every time (like a live performer)

[aefa]

tulamide! Thank you very much for your assessment! I don't understand half of the issues you pointed but I'll definitely go through your points and try and sort it out. Indeed I see these problems happen specially when triggering the fill because that is the one that tends to stay on after the trigger. I've been trying to recreate all this using mostly primitives because my ruby mastery amounts to googling what I need to do at the moment I'll keep updating my progress (if any)

[aefa]

The music I make is Latin and Caribbean, which rely heavily on percussion. When the percs have hardcoded patterns it sounds monotone and boring. I don't know if the forum allows for video posting so I could upload a visual of how I intend to use this.

[Spogg]

... I don't know if the forum allows for video posting so I could upload a visual of how I intend to use this.

You could upload the video to YouTube and make it private then share the link here…

[aefa]

You could upload the video to YouTube and make it private then share the link here…

Thank you Spogg. I'll do that!