Hi, does anyone have an example on how to implemen...

# javascript

[rnentjes]

Hi, does anyone have an example on how to implement an AudioWorkletProcessor in kotlin?

According to the documentation it should be possible to just override the external class AudioWorkletProcessor but I get the following error in chrome:

AudioWorklet.kt:55 Uncaught TypeError: Failed to execute 'registerProcessor' on 'AudioWorkletGlobalScope': Property "process" doesn't exist

This is how I defined the external interface:

external interface AudioWorkletProcessor {

    fun process(
        inputs: dynamic,
        outputs: dynamic,
        parameters: dynamic
    ): Boolean

}

This is the actual class:

class MyAudioProcessor : AudioWorkletProcessor {

    override fun process(
        inputs: dynamic,
        outputs: dynamic,
        parameters: dynamic
    ): Boolean {
        println("process")
        if (outputs.isNotEmpty()) {
            if (outputs[0].size == 2) {
                println("found one output with 2 channels")
            }
        }

        return true
    }

}

The registerProcessor function expects a class constructor, I use ::MyAudioProcessor. Maybe that should be something else?

Btw, firefox gives this error message:

TypeError: Return value of AudioWorkletProcessorConstructor does not implement interface AudioWorkletProcessor.

[turansky]

Possibly port required

[turansky]

I use ::MyAudioProcessor

Try MyAudioProcessor::class.js instead

[rnentjes]

Ah, great. The ::class.js was the problem. Thx!

[rnentjes]

Hmm, this didn't actually work, it doesn't give an error but it also doesn't give me an actual AudioWorkletProcessor, just some object which doesn't do anything.

[rnentjes]

Looks like the AudioWorkletProcessor needs to be defined as a class. But if I do that I get the following error:

Uncaught TypeError: Failed to construct 'AudioWorkletProcessor': Please use the 'new' operator, this DOM object constructor cannot be called as a function.
at new ol (AudioWorklet.kt:24)

[rnentjes]

Btw, I am trying this with version 1.4-M2, so it wouldn't surprise me if there is a bug in the javascript generation.

[turansky]

Root cause

[turansky]

Looks like you need ES6 target for AudioWorkletProcessor