Compiled Network Fixed Channel Count?

[David Healey]

Little spin off from another thread.

It seems when I compile a network I have to decide exactly how many audio channels it will use.

For example if I make a network that I want to reuse in multiple projects that each have a different number of channels, I need to maintain multiple versions of the same network just with different channel amounts.

Is this correct or am I missing something obvious?

[Stuart Cochrane]

Hi David, I am new to HISE i am adding the core.faust scriptnode to script fx and its crashing HISE, looks like its trying to recompile faust code.
when I click on any one of the dsp networks HISE shuts down instantly.
Any help would be greatly appreciated.

[David Healey]

@Stuart-Cochrane Make a separate thread

[Christoph Hart]

@David-Healey Yes that is the case - the optimization possibilities that come from assuming a fixed channel were too tempting.

IIRC Faust also assumes some kind of known channel set, no?

[David Healey]

@Christoph-Hart Would it be possible to make it still work with fewer channels without sacrificing optimisation? For my framework I want to support projects from 2 to 16 channels but I don't want to maintain that many versions of each effect. If I could just make a 16 channel version that would be good.

[Christoph Hart]

@David-Healey what's the effect? just a mixer?

If you use it in different projects we might solve this by allowing FixChannelAmount to be a preprocessor, then it can pull in the actual channel count from the project it compiles the DLL too? So if Project A needs 6 channels, but Project B needs 16, you can just enter NUM_PLUGIN_CHANNELS (or whatever preprocessor you define) and it should cleanly pass that through to the C++ code generator.

[David Healey]

@Christoph-Hart said in Compiled Network Fixed Channel Count?:

what's the effect? just a mixer?

I have my multi-channel simple gain thingy and a couple of filters (until the stock filter is fixed anyway).

I'd prefer to stay clear of scriptnode but I have some releases upcoming and it seems like the best way to get around the current issues I'm having.

@Christoph-Hart said in Compiled Network Fixed Channel Count?:

If you use it in different projects we might solve this by allowing FixChannelAmount to be a preprocessor

I don't think that will work because my projects are all expansions for Rhapsody, so the count will be fixed at the player level.

[Christoph Hart]

@David-Healey but with rhapsody you cannot pull in compiled effects anyway unless you embed them in the player binary - that's the one hard restriction that comes with the full player expansion system.

[David Healey]

@Christoph-Hart My plan is to embed them in the binary since I need them in almost every project

[Christoph Hart]

@David-Healey ah ok. BTW are you sure you need to compile them? If you're just using a simple multi channel DSP network with multiple gain modules in a container.multi container, then the DSP overhead is negligible - definitely lower than the old scripting approach.

[David Healey]

@Christoph-Hart said in Compiled Network Fixed Channel Count?:

definitely lower than the old scripting approach.

In that case no I probably don't need to compile them, so that solves it :)

[David Healey]

@Christoph-Hart Hmm I just realised I have the same problem, when I bring in my dsp xml that's setup for 16 channels into a project with only 6 it reds everything out and tells me there aren't enough channels.

So I remove the extra ones but then I'm left with another file to maintain in my framework so it doesn't really make the situation any easier. If it was just one effect it wouldn't be an issue but this seems like it will be the same for any scriptnode effect I want to use with Rhapsody.

Or will it still work but just show the angry red box?

[Christoph Hart]

@David-Healey nope, won't work.

What if you actually create the network dynamically?

// define this somewhere in your interface script
global NUM_CHANNELS = 8;

// Put this code in a Script FX that is set to use the number of channels
const var dsp = Engine.createDspNetwork("mixer");

const var mixer = dsp.get("mixer");
const var multi = dsp.createAndAdd("container.multi", "multi", "mixer");

for(i = 0; i < (NUM_CHANNELS/2); i++)
{
	// create a gain module
	var g = dsp.createAndAdd("core.gain", "gain" + (i+1), multi);
	
	// fetch the gain parameter
	var dst = g.getOrCreateParameter("Gain");
	
	// create a root parameter
	var src = mixer.getOrCreateParameter({
	    "ID": "Gain" + (i+1),
	    "mode": "Decibel"
	});
	
	// connect the two
	dst.addConnectionFrom({ID: "mixer", "ParameterId": "Gain" + (i+1)});
	
	// copy the range to the source parameter
	// (make the warning icon disappear...)
	src.setRangeFromObject(dst.getRangeObject());
}

[David Healey]

@Christoph-Hart Ahh that's an idea, I haven't explored that side of scripting. I could pull the number of channels from the master container's routing matrix. No I can't, no access to Synth within the script FX :(

[ustk]

@David-Healey Can you do it from the UI script?

const var ScriptFX_RM = Synth.getRoutingMatrix("ScriptFX"); // or master chain...

global NUM_CHANNELS = ScriptFX_RM.getNumSourceChannels();

[David Healey]

@ustk I found a better solution to get the channel count
https://github.com/christophhart/HISE/pull/957

[David Healey]

My network contains a lot more than just some gains so recreating it all via scripting is a pain and means I don't get to work with the nice GUI. Is there a simple build network from JSON type thing? Edit: dsp.createFromJSON might be it..

Another option I thought of is I can park all the chains in the multi as unused nodes, then in the script use this to add them for just the number of channels:

const dsp = Engine.createDspNetwork("SimpleGain");
const numChannels = dsp.getNumChannels();
const multi = dsp.get("multi");
const numPairs = numChannels / 2;
   
for (i = 0; i < numPairs; i++)
	dsp.get("chain" + i).setParent(multi, i);

This works for my multi channel simple gain because each channel has its own chain, but I don't think it would be a good general solution for all networks.