Xpresso & Pyhton - Convert Link List (Hierarchy Node) to In-/Exclusion

hoffwerr

Hi there!
I'm trying to convert the output of a Hierarchy Node into an In-/Exclusion list.
I've done quite a bit of research to try to figure this one out but I'm honestly not a coder and I couldn't figure it out at all.

This is kind of of what I'm trying to do.

Any change I can get some help on this.

Thanks!

i_mazlov

Hi @hoffwerr ,

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About your First Question

Please elaborate on what exactly you're trying to achieve? Why do you need a python node here, wouldn't it be enough using ObjectList node instead? What exactly do you mean by "convert to In-Exclusion list"?

Please don't be shy to attach a sample project file that shows where you are currently at.

Cheers,
Ilia

hoffwerr

Hi @i_mazlov ,

Thanks for getting back to me about my question. I'm basically trying to auto populate the "Effectors" list in the Group Effector with whatever effectors are child of it. I thought I'd just use a Hierarchy node and somehow plug that in directly in that Effectors with Xpresso but it turned out to be not straight forward as I thought.

So my idea was to somehow setup a quick python script where it would cycle through the Hierarchy node output and add them all into an In-Exclusion list. I think the ObjectList is exactly the opposite of what I'm trying to do. The Input is an In-Exclusion list while the output is an Object/Instance.

Not sure what would be the Ideal workflow for something like this.

hoffwerr

Ok. I did some more research and I think I'm kinda close to figuring this out. I ended up using a Python tag instead.

import c4d

def main():
    obj = op.GetObject()
    print (obj)
    effectors = obj.GetChildren()
    print (effectors)
    
    GroupList = c4d.InExcludeData()
    GroupList.InsertObject(effectors, 1)
    obj[c4d.MGGROUPEFFECTOR_EFFECTORLIST] = GroupList
    
    c4d.EventAdd()

Seems to work just fine up until adding the selection to the InExcludeData

<c4d.BaseObject object called Group/Group with ID 1019351 at 1949340925248>
[<c4d.BaseObject object called Plain.2/Plain with ID 1021337 at 1949342765760>, <c4d.BaseObject object called Plain.3/Plain with ID 1021337 at 1949342765632>, <c4d.BaseObject object called Plain.4/Plain with ID 1021337 at 1949342766400>]
Traceback (most recent call last):
  File "Python", line 10, in main
TypeError: argument 1 must be c4d.BaseList2D, not list

I'm getting this error at the bottom with the objects being a "list" instead of "c4d.BaseList2D". Can't seem to figure this one out.

hoffwerr

Ok, I did some more research and found some old topic with a similar problem. This seems to work for me at least. I'm able to get all the child objects and auto add them to the InExcludeData.

import c4d

def AddHierarchyToInEx(obj, inex) :
    if obj is None:
        return
    while obj is not None:
        inex.InsertObject(obj, 1)
        AddHierarchyToInEx(obj.GetDown(), inex)
        obj = obj.GetNext()


def main():
    obj = op.GetObject()
    InExData = c4d.InExcludeData()
    AddHierarchyToInEx(obj.GetDown(), InExData)
    obj[c4d.MGGROUPEFFECTOR_EFFECTORLIST] = InExData

    c4d.EventAdd()

hoffwerr

This is based from this thread.
https://developers.maxon.net/forum/topic/10016/13482_python-node-with-hierarchy/4

But it's unfortunately causing crashes. It seems to be returning every single object under the main object so all the children and grand children, etc. Is there anyway to limit this to just the children ?

hoffwerr

@hoffwerr said in Xpresso & Pyhton - Convert Link List (Hierarchy Node) to In-/Exclusion:

Ok. I did some more research and I think I'm kinda close to figuring this out. I ended up using a Python tag instead.
import c4d

def main():
    obj = op.GetObject()
    print (obj)
    effectors = obj.GetChildren()
    print (effectors)
    
    GroupList = c4d.InExcludeData()
    GroupList.InsertObject(effectors, 1)
    obj[c4d.MGGROUPEFFECTOR_EFFECTORLIST] = GroupList
    
    c4d.EventAdd()
Seems to work just fine up until adding the selection to the InExcludeData
<c4d.BaseObject object called Group/Group with ID 1019351 at 1949340925248>
[<c4d.BaseObject object called Plain.2/Plain with ID 1021337 at 1949342765760>, <c4d.BaseObject object called Plain.3/Plain with ID 1021337 at 1949342765632>, <c4d.BaseObject object called Plain.4/Plain with ID 1021337 at 1949342766400>]
Traceback (most recent call last):
  File "Python", line 10, in main
TypeError: argument 1 must be c4d.BaseList2D, not list
I'm getting this error at the bottom with the objects being a "list" instead of "c4d.BaseList2D". Can't seem to figure this one out.

I'm really confused on why "GetChildren" doesn't work while GetNext and GetDown seem to work just fine. GetChildren seems like it's the ideal way to do this since I only want the children and none of the grand children.

i_mazlov

Hi @hoffwerr ,

Please check our Support Procedures about consolidating consequent answers in a single posting. Please also do not duplicate your threads!

I assume this question was answered in your second thread: GetChildren into an InExcludeData.

Cheers,
Ilia