When C4D is in Polygon mode
Grow selection can be done using
utils.SendModelingCommand( c4d.MCOMMAND_SELECTGROW, [op], c4d.MODELINGCOMMANDMODE_POLYGONSELECTION, c4d.BaseContainer(), doc )
After that, selection grows to neighbour polygons. Everithing is ok.
However, when active mode is UV Polygon then code above select neighbour polygons the same way how it was in previous case. Sometime it's ok, but not always.
The second way to grow selection is to use
c4d.CallCommand(12558, 12558) # Grow Selection
In this case selection grows correctly in both modes.
I'll show an example. There is a simple sphere that separated by UVs in the middle. So it has 2 UV islands.
From 1 selected polygon (the first image) I want to get the result which is shown on the last image.
But I don't know how to get it without
Sorry for mistakes. English is not my szcznek language