Best way to call async method from processBlock() loop?

Audio Plugins
8

Thanks all for the interesting insights!

My take on the first approach (flag + timer) was this (it’s for a IR convolution plugin)…

class ImpulseLoaderAsync  : private Timer
{
public:
    ImpulseLoaderAsync();

    void changeImpulseAsync (int newImpulse);
    const bool isNowChanging() { return nowChangingImpulseAsync; }

private:
    int currentImpulse {-1};    // force initial load
    bool nowChangingImpulseAsync {false};      // the flag

    void timerCallback() override;
    void changeImpulse (int newImpulse);
};

.cpp…

#include "ImpulseLoaderAsync.h"

ImpulseLoaderAsync::ImpulseLoaderAsync()
{
    startTimer (500);
}

void ImpulseLoaderAsync::changeImpulseAsync (int newImpulse)
{
    if (newImpulse != currentImpulse)
    {
        currentImpulse = newImpulse;
        nowChangingImpulseAsync = true;
    }
}

// private:

void ImpulseLoaderAsync::timerCallback()
{
    if (nowChangingImpulseAsync)
    {
        changeImpulse (currentImpulse);
        nowChangingImpulseAsync = false;
    }
}

void ImpulseLoaderAsync::changeImpulse (int newImpulse)
{
    switch (newImpulse)
    {
        // big switch statement where I load the impulse
    }
}

Note, I bypassed the DSP (in my case convolution) whenever the changeImpulseAsync() flag is set.

In the processBlock()…

impulseLoaderAsync.changeImpulseAsync (newImpulse);

if (*bypassParam < 0.5f && impulseLoaderAsync.isNowChanging() != true) // bypass while changing impulse also
{ 
    //... the DSP

How does all this look to you guys best practice-wise?

Thanks!