rnbo-svelte

rnbo-svelte is a node package for abstracting away repetitive tasks that are needed to work with RNBO in a node-based application.

What does it offer?

As of writing this, there are three major things offered by this package.

createDeviceInstance(devicePath, context, output) is a function for creating a new instance of an RNBO device. You devicePath is a JSON bundle exported from RNBO and you also supply an AudioContext object and an output GainNode.

sendDeviceMessage(device, tag, message) is a function for sending a message to an RNBO device via an inport. I tend to prefer the inport instead of the param as it allows you to send arrays into the device. You lose the ability to setup @enum and set minima and maxima, but that's a worthwhile tradeoff in my personal use cases.

loadSamples is a function for easily loading a bundle of samples into buffers which are structured as a JSON object. Because this returns a promise, it supports chaining it after a device instance is created, ideally via createDeviceInstance.

Usage Examples

You can see an example here in the intersymmetric project of loadSamples and createDeviceInstance being used to instantiate a device and then load a bundle of audio samples into the devices buffers.

<script>
    import Interface from './Interface.svelte';
    import Button from './Button.svelte';
    import { loadSamples, createDeviceInstance } from '@jamesb93/rnbo-svelte';

    let patch, context;
    let samplesLoaded = false;

    const start = async () => {
        context = new (window.AudioContext || window.webkitAudioContext)();
        let output = context.createGain().connect(context.destination);
        createDeviceInstance('/nyege/code/patch.export.json', context, output)
        .then(response => {
            patch = response;
            const samples = new Array(33).fill(0).map((_, i) => ({
                url: `/nyege/samples/${i}.mp3`,
                buffer: `b.${i+1}`
            }))
            loadSamples(patch, context, samples);
            samplesLoaded = true;
        });

    };
</script>

You can also see an example of sendDeviceMessage here, where a reactive statement fires off messages to the device everytime some state in a Svelte store changes.

$: sendDeviceMessage(patch, 'polymetric_params', [0, $range0, $div0]);

Contribution

Open a PR, or just get in touch with me at github@jamesbradbury.net.