The heavy hvcc compiler for Pure Data patches. Updated to python3 and additional generators

View the Project on GitHub


Heavy can generate LV2, VST2, VST3, and CLAP plugins from your patch using the Distrho Plugin Framework. It can be either a synth (output-only) or an effect (input and output), supports an arbitrary number of parameters, and can process midi events.

Some examples are built for the major operating systems (Linux/Windows/MacOS) in various formats (LV2/VST2/VST3/CLAP).

Defining Parameters

Each exposed parameter will automatically generate a slider in the plugin interface.

MIDI Control

In order to receive MIDI note on and off events, as well as control change messages, the [notein] and [ctlin] objects should be used, respectively.

DPF supports all note/ctl/pgm/touch/bend I/O events. The implementation is further discussed in the midi docs

We can also use [midirealtimein] to receive realtime midi messages like clock/start/continue/stop/reset (no active sense). It is up to the user to create the appropriate handling inside the patch.

Additionally you can use the special [r __hv_dpf_bpm] receiver to get the current transport BPM value directly.


Parameter Types

In DPF a parameter can get an optional type configured. The default type is float. Other assignable types are bool - for toggling a value - and trig - for momentary signals.


Using jinja the v.attributes.type can be evaluated for a specific string and different templating applied to the parameter. In DPF the extra types bool and trig result in the following plugin code:

        parameter.hints = kParameterIsAutomable | kParameterIsBoolean;
// or
        parameter.hints = kParameterIsAutomable | kParameterIsTrigger;


An accomponying metadata.json file can be included to set additional plugin settings.

The project flag creates a README.md and Makefile in the root of the project output, but may conflict with other generators.

Each of these are optional and have either a default value or are entirely optional (description and homepage). Midi i/o ports are on by default, but can be set to 0 and they will be disabled - currently midi_input always has to be on!.

    "dpf": {
        "project": true,
        "description": "super simple test patch",
        "maker": "nobody",
        "homepage": "https://wasted.audio/plugin/dpf_example",
        "plugin_uri": "lv2://wasted.audio/lv2/dpf_example",
        "version": "6, 6, 6",
        "license": "WTFPL",
        "midi_input": 1,
        "midi_output": 0,
        "plugin_formats": [

Other fields that the DPF metadata supports are:

An example plugin that uses some of these extended metadata is WSTD 3Q.