Audio arguments

Supported bindings: ossia, vst, vst3, clap, Max, Pd

In addition of the global set-up step, one may require per-process-step arguments. Most common needs are for instance the current tempo, etc.

The infrastructure put in place for this is very similar to the one previously mentioned for the setup step.

The way it is done is simply by passing it as the last argument of the processing operator() function.

If there is such a type, it will contain at least the frames.

Note: due to a lazy developer, currently this type has to be called tick.

Example:

struct MyProcessor {
  ...

  struct tick {
    int frames;
    double tempo;
  };

  void operator()(tick tick) { ... }
  float operator()(float in, tick tick) { ... }
  void operator()(float* in, float* out, tick tick) { ... }
  void operator()(float** in, float** out, tick tick) { ... }

  // And also the versions that take input and output types as arguments
  void operator()(const inputs& in, outputs& out, tick tick) { ... }
  float operator()(float in, const inputs& in, outputs& out, tick tick) { ... }
  void operator()(float* in, float* out, const inputs& in, outputs& out, tick tick) { ... }
  void operator()(float** in, float** out, const inputs& in, outputs& out, tick tick) { ... }

  // And also the double-taking versions, not duplicated here :-)
};

The currently supported members are:

  • frames: the buffer size

The plan is to introduce:

  • tempo and all things relative to musicality, e.g. current bar, etc.
    • But first we have to define it in a proper way, which is compatible with VST, CLAP, etc.
  • time_since_start
  • and other similar timing-related things which will all be able to be opt-in.