pure-data VS pure-data

> The other advantage is because these things were implemented in the 80s

Pd was developed in the mid 90s

> they are very computationally efficient

Not as efficient as it could be, though. For example, instead of proper SIMD instructions, the DSP perform routines only use manual loop unrolling, praying that the compiler will auto-vectorize it.

Finally, everything is single-threaded, leaving lots of performance on the table. FWIW, I have a PR for an asynchronous task API (https://github.com/pure-data/pure-data/pull/1357) and also a branch for multi-threaded DSP (https://github.com/Spacechild1/pure-data/tree/multi-threadin...).

FWIW, Pd and Max/MSP always had sample-level control in the sense that subpatches can be reblocked. For example, if you put a [block~ 1] object in a Pd subpatch, the process function will be called for every sample, so you can have single-sample feedback paths. Pd also has the [fexpr~] object which allows users to write FIR and IIR filters in a simple expression-syntax. Finally, Max/MSP offers the very powerful [gen~] object. You can check it out for inspiration (if you haven't already).

Pd (and Max/MSP) also allow to upsample/resample subpatches, which is important for minimizing aliasing (caused by certain kinds of processing, such as distortion).

Pd also uses the reblocking mechanism to implement FFT processing. The output of [rfft~] is just an ordinary signal that can be manipulated by the usual signal objects. You can also write the output to a table, manipulate it in the control domain with [bang~], and then read it back in the next DSP tick. IMO, this is a very powerful and elegant approach. SuperCollider, on the other hand, only supports a single global blocksize and samplerate which prevents temporary upsampling + anti-aliasing, severly limits single-sample feedback and leads to a rather awkward FFT implementation (you need dedicated PV_* objects for the most basic operations, such as addition and multiplication).

Another thing to think about is multi-threaded DSP. With Supernova, Tim Blechmann miraculously managed to retrofit multi-threading onto scsynth. Max/MSP offers some support for multi-threading (IIRC, top level patches and poly~ instances run in parallel). Recently, I have been working on adding multi-threading to Pd (it's working, but still very much experimental): https://github.com/Spacechild1/pure-data/tree/multi-threadin.... If you design an audio engine in 2022, multi-threading should be considered from the start; you don't have to implement it yet, but at least leave the door open to do it at a later stage.

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I'm not sure how far you want to go with Glicol. I guess for the typical Algorave live coder all these things are probably not important. But if you want Glicol to be a flexible modern audio engine/library, you will have to think about FFT, upsampling, single-sample feedback, multi-processing etc. at some point. My advice is to not leave these things as an afterthought; you should at least think about it from the start while designing your engine - if you want to avoid some of the mistakes that other existing audio engines made. This is just a word of "warning" from someone having spent countless of hours in Pd and SuperCollider source code :-)

Great write up!

What I like about Pd is that you can freely reblock and resample any subpatch. Want some section with single-sample-feedback? Just put a [block~ 1]. You can also increase the blocksize. Usually, this is done for upsampling and FFT processing. Finally, reblocking can be nested, meaning that you can reblock to 1024 samples and inside have another subpatch running at 1 sample blocksize.

SuperCollider, on the other hand, has a fixed global blocksize and samplerate, which I think is one of its biggest limitations. (Needless to say, there are many things it does better than Pd!)

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In the last few days I have been experimenting with adding multi-threading support to Pd (https://github.com/Spacechild1/pure-data/tree/multi-threadin...). With the usual blocksize of 64 sample, you can definitely observe the scheduling overhead in the CPU meter. If you have a few (heavy-weight) subpatches running in parallel, the overhead is neglible. But for [clone] with a high number of (light-weight) copies, the overhead becomes rather noticable. In my quick tests, reblocking to 256 samples already reduces the overhead significantly, at the cost of increased latency, of course.

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Also, in my plugin host for Pd/Supercollider (https://git.iem.at/pd/vstplugin/) I have a multi-threading and bridging/sandboxing option. If the plugin itself is rather lightweight and the blocksize is small, the scheduling overhead becomes quite noticable. In Pd you can just put [vstplugin~] in a subpatch + [block~]. For the SuperCollider version I have added a "reblock" argument to process the plugin at a higher blocksize, at the cost of increased latency.

Report bugs on the pd github https://github.com/pure-data/pure-data

You might be interested in clicking through the puredata source code.

https://github.com/pure-data/pure-data

> The other advantage is because these things were implemented in the 80s

Pd was developed in the mid 90s

> they are very computationally efficient

Not as efficient as it could be, though. For example, instead of proper SIMD instructions, the DSP perform routines only use manual loop unrolling, praying that the compiler will auto-vectorize it.

Finally, everything is single-threaded, leaving lots of performance on the table. FWIW, I have a PR for an asynchronous task API (https://github.com/pure-data/pure-data/pull/1357) and also a branch for multi-threaded DSP (https://github.com/Spacechild1/pure-data/tree/multi-threadin...).

> Any criticism or unwelcome suggestions are treated as an insult to Miller Puckette and the proponent is attacked, ignored, or advised to implement it themselves (ie to go away and not come back).

I don't think this holds for the general case, but there a certainly a few users caught up in Stockholm Syndrome :-) I can assure you that the developer team (which I am a part of) is very well aware of Pd's limitations and problems. Pd has seen quite significant UX improvements over the last few years, but the pace of development is very slow. Anyway, if you have specific criticism, suggestions or feature requests, feel free to open a ticket on GitHub: https://github.com/pure-data/pure-data.

As a side note, the minimalistic GUI itself won't change since it is an intentional design decision by Miller, but there is some effort to abstract the core/GUI communication to allow alternative GUI implementations. (Personally, I really dislike the current Tcl/Tk GUI - not because it's minimalistic, but because it's slow and buggy.)

> and idiosyncratic terminology (eg PD refers to module connectors as 'patch cords' just like on an analog modular synthesizer or mixer, but what synth people commonly call a pulse or a trigger is a 'bang' in PD).

Pd's 'bang' belongs to the control/event domain, you can't really compare it to trigger/pulse in modular synthesizers. (FWIW, there are several Pd externals that implement audio-rate triggers.)

> You can make it do anything, but unless you already have a very specific goals you will spend most of the time reinventing wheels in parameter space.

That's a fair point. It's important for people to understand that Pd vanilla is really a programming environment with only a minimal set of built-in objects that allow you to build higher-level abstractions. You definitely need a set of "abstractions" or libraries to be productive. Fortunately, there are many existing Pd libraries and they can be easily installed with Pd's package manager "Deken". The most extensive one is "ELSE" with nearly 500 objects, containing everything from band-limited ocillators, filters, sequencers, GUIs, etc. Personally, I have my own collection of abstractions that I made over the last years.

That being said, I would agree that you should always pick the right tool for the job. Just as you wouldn't write your website in C, you wouldn't pick Pd for typical EDM stuff (unless you have a very good reason). But for prototyping and experimental electronics it's a fantastic tool, I think.