startSection for custom parameters in C++ Custom OPs

When creating parameters for a C++ Custom Operator in setupParameters(),
there is currently no way to set startSection on a parameter. Neither
OP_NumericParameter nor OP_StringParameter has a section field, and since
the parameters are plugin-defined they can’t be adjusted from Python
afterwards either.

COMP custom parameters already support this via par.startSection, and
built-in operators use it everywhere, so C++ Custom OPs end up being the
only parameter pages that can’t be visually grouped the same way.

Request: add a startSection bool to OP_NumericParameter and
OP_StringParameter (or an equivalent flag in the append calls) so a
parameter can start a new section.

While on the subject of parameter layout for Custom OPs: the auto-generated
“Callbacks DAT” parameter from customOPInfo.pythonCallbacksDAT is placed on
its own “Custom” page with no way to choose which page it lands on. Being
able to place it (e.g. on a page defined in setupParameters()) would let us
keep all callback-related parameters together.

Hey @huitresix ,

The latest 2025 release, 2025.33070, allows OP_StringParameter::section or OP_NumericParameter::section to be specified which does what the python .startSection option does. Could you try this out?

Allowing the callbacks DAT parameter to be placed on a specific page does sound reasonable. We have added it to our list to be looked at.

Varad

1 Like

Hey thanks for the answer !

Unfortunately I’m on .32820 for my current project but I’ll try it out as soon i bump up the version on the next project !