Discussion: Dealing with incomplete GDD-type implementations

[dvdeurse]

With GDD in place, we already have quite a few parameter types. And there are proposals for even more types:

• Suggestion: GDD graphics positions #47
• Proposal for new GDD Type: select multiple #37
• Proposal for new GDD type: Scan folder #23

For OGraf Renderer and Controller implementations, it is not trivial to support all these types. In LiveOS for example, we only support the types that were already there in our Graphics Engine, as a first step. I can imagine we're not alone and other implementers skip some types as well.

How do we deal with these 'partial' implementations? Some options I see:

• just state that an implementation is "not compliant" when not implementing all the types
• describe the minimal set of types that need to be implemented to be compliant and come up with a fallback plan for the remaining types
• come up with a mechanism for announcing which types are supported?

I think the second option is the cleanest and also how GDD was originally designed I guess (Johan?). However, we should be more explicit in the text on how implementers of renderers and controllers should deal with it.

[nytamin]

Agreed, it would be good to discuss this in the group and decide on some minimal level of gdd-types to support.

FYI 1:
A fallback mechanism is already defined in the GDD docs, as all gdd-types are designed to fall back to simpler gdd-types, then to the Basic types ("boolean", "string", "number", "integer", "array", "object").
This way a GUI won't have to support all gdd-types

FYI 2:
I've implemented a OGraf/GDD-form library, that can render input forms for gdd-schemas, hopefully this will be useful to application implementers going forward.

[didikunz]

Today in the meeting (2026-03.04) Tumno came up with a valid point, that a the GUI for an object (and also and array) could fallback to display a (multi-line) text-box containing the JSON. In the light of that quote I see no reason to restrict the use of any of the less common basic and GDD types.

[nytamin]

(sorry for being a day late on these notes)
Notes from OGraf Meeting 2026-03-04:

There was a discussion on how Vendors can promote which GDD-types they have implemented.

• The MOS Protocol has "profiles" that defines different functionality areas. Perhaps we could be inspired by that
• Also the MIDI specification has a similar approach and has been very successful.

There is also a need do describe what is required from a GUI to be compliant (with emphasis on complex data types sych as objects and arrays).

No conclusions reached, discussion to continue at a later time.