DPF/FEATURES.md

DPF - DISTRHO Plugin Framework

This file describes the available features for each plugin format.
The limitations could be due to the plugin format itself or within DPF.

Feature	JACK/Standalone	LADSPA	DSSI	LV2	VST2	VST3
Audio port groups	Yes*	No	No	Yes	No	No*
Audio port as CV	Yes	No	No	Yes	No	No*
Audio sidechan	Yes	No	No	Yes	No*	No*
Bypass control
MIDI input	Yes	No	Yes	Yes	Yes	Yes
MIDI output	Yes	No	No	Yes	Yes	Yes
Parameter changes	Yes	No	No	No*	Yes	Yes
Parameter groups	No	No	No	Yes	Yes*	No*
Parameter outputs	No	No	No	Yes	Yes	No*
Parameter triggers
Programs	Yes*	No*	Yes*	Yes	No*	Yes
States	Yes	No	Yes*	Yes	Yes	Yes
Full/internal state
Time position
UI	Yes*	No	Ext.	Embed or Ext.	Embed	Embed
UI bg/fg colors
UI direct access
UI host-filebrowser
UI host-resize	Yes	No	Yes	Yes	No	No*
UI remote control
UI sendNote	Yes	No	Yes	Yes	Yes	Yes

For things that could be unclear:

• “States” refers to DPF API support, supporting key-value string pairs for internal state saving
• “Full state” refers to plugins updating their state internally without outside intervention (like host or UI)
• “UI direct access” means DISTRHO_PLUGIN_WANT_DIRECT_ACCESS is possible, that is, running DSP and UI on the same process
• “UI remote control” means running the UI on a separate machine (for example over the network)

Special notes

JACK audio port groups

DPF will set JACK metadata information for grouping audio ports.
This is not supported by most JACK applications at the moment.

JACK parameters and programs

Under JACK/Stanlone mode, MIDI input events will trigger program and parameter changes.
MIDI program change events work as expected (that is, MIDI program change 0 will load 1st plugin program).
MIDI CCs are used for parameter changes (matching the midiCC value you set on each parameter).

JACK custom UI only

There is no generic plugin editor view.
If your plugin has no custom UI, the standalone executable will run but not show any window.

LADSPA programs

Programs for LADSPA could be done via LRDF but this is not supported in DPF.

DSSI State

DSSI only supports states when called via UI, no “full state” possible

LV2 parameter changes

Possible through a custom extension, not implemented on most hosts.
For now you can pretty much assume it is not supported.

VST2 potential support

Not supported in DPF at the moment.
It could eventually be, but likely not due to VST2 being phased out by Steinberg.
Contact DPF authors if you require such a feature.

VST2 programs

VST2 program support requires saving state of all programs in memory, which is very expensive and thus not done in DPF.

VST3 is work in progress

Feature is possible, just not implemented yet in DPF.