The main thing that now needs thinking through is what to do for a standard VST3 interface - there shuold be some way for the patch to put controls on the VST3 surface, perhaps using Steinberg's own GUI-building nonsense in some way so that things look like a normal VST if you don't get around to opening the Pd GUI.
I think you can just add a certain number of generic parameters that are bound to a predefined symbol, e.g. pd-vst-param <number> <value>. The question just how many :)
Note that the parameter configuration must be fixed! Specifically, parameters can only be added (or removed) in future plugin versions. See https://steinbergmedia.github.io/vst3_dev_portal/pages/Technical+Documentati....
You can, however, change the parameter *names* at runtime, see https://steinbergmedia.github.io/vst3_dev_portal/pages/Technical+Documentati....
You could simply make the parameter names editable in the VST GUI and save them as part of the plugin state. In addition, you could add a Pd message that allows users to rename parameters on the patch level, e.g. pd-set-vst-param-name <number> <name>.
(You can add an option to hide unused parameters in the VST GUI, but they will still show up in the list of automatable parameters and in the generic plugin UI.)
There are quite a few VSTis with hundreds of parameters, so I think you can just add something like 256 parameters and hope that people won't need more :)
If you have more questions about the VST3 SDK itself, you can also contact me off-list.
Christof
cheers Miller
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