SetParameter Returns True but Doesn't Update UV Grid Checkbox in C4D

shahir zaman

I'm having this issue where using C4DAtom::SetParameter is returning true as if the updated value was set but it isn't being set, UV_SETTINGS_FILTER_SHOW_GRID is being passed but it isn't actually updating the show UV grid checkbox on the filter tab.
attempting to make a grid based uv packer.
help would be greatly appreciated.

i_mazlov

Hi @shahir-zaman ,

Welcome to the Maxon developers forum and its community, it is great to have you with us!

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It is strongly recommended to read the first two topics carefully, especially the section Support Procedures: Asking Questions.

About your First Question

Assuming that what you're trying to achieve is to toggle the "UV Grid" option

You effectively have two options:

The easiest one is to execute CallCommand(170776) (you can find the command ID in the Script Log)
The more involved but also more flexible way is to find the UV settings scenehook and go through all its branches (or may be not all of them, depending on what specifically you want to achieve). Please find the C++ and Python code snippets below.

Cheers,
Ilia

C++ commanddata execute function code snippet:

Bool MyCommandData::Execute(BaseDocument* doc, GeDialog* parentManager)
{
  const Int32 ID_UV_SETTINGS_HOOK = 1053309;
  
  if (!doc)
    return true;
 
  BaseSceneHook* sceneHook = static_cast<BaseSceneHook*>(doc->FindSceneHook(ID_UV_SETTINGS_HOOK));
  if (!sceneHook)
    return true;
 
  maxon::BufferedBaseArray<BranchInfo, 20> infos;
  sceneHook->GetBranchInfo(infos, GETBRANCHINFO::NONE) iferr_ignore("GetBranchInfo");
 
  for (BranchInfo& info : infos)
  {
    if (info.name != "UVSettingsBranch"_s)
      continue;
 
    GeListNode* viewSettings = info.head->GetFirst();
    while (viewSettings)
    {
      GeData value;
      viewSettings->GetParameter(CreateDescID(UV_SETTINGS_FILTER_SHOW_GRID), value, DESCFLAGS_GET::NONE);
      Bool valueBool = value.GetBool();
 
      value = {!valueBool};
 
      viewSettings->SetParameter(CreateDescID(UV_SETTINGS_FILTER_SHOW_GRID), value, DESCFLAGS_SET::NONE);
 
      viewSettings = viewSettings->GetNext();
    }
  }
 
  EventAdd();
 
  return true;
}

Python script code snippet (special thanks to @m_adam on this one):

import c4d

def main() -> None:
    sh = doc.FindSceneHook(1053309)
    for branch in sh.GetBranchInfo():
        if branch["name"] != "UVSettingsBranch":
            continue
        
        viewSettings = branch["head"].GetFirst()
        while viewSettings:
            viewSettings[c4d.UV_SETTINGS_FILTER_SHOW_GRID] = not viewSettings[c4d.UV_SETTINGS_FILTER_SHOW_GRID]
            viewSettings = viewSettings.GetNext()       
        
    c4d.EventAdd()

if __name__ == '__main__':
    main()