Maya python get top most parent transforms

Question

I have a selection of transforms in maya and I want to get the top parent transforms of all hierarchies within the selection. Is this the best way to achieve that?

import maya.cmds as cmds
def getTopParents(transforms):
    '''
    Returns a list of the top most parents for the given transforms
    '''
    parents = []
    for t in transforms:
        p = cmds.listRelatives(t, parent=True, type='transform')
        while p:
            p = cmds.listRelatives(p[0], parent=True, type='transform')
        if p:
            parents.append(p[0])
        else:
            parents.append(t)

    return parents

Asked By: JokerMartini

||

Source

Answer 1

How about something like this? Modify as needed to store the parents instead of just printing them.

import maya.cmds as cmds

targets = ['pCylinder1', 'group4', 'group10']

print('Full hierarchy: {}'.format(cmds.ls(targets[0], long=True)[0]))

for target in targets:
    parent = None
    stop = False
    
    while not stop:
        p = cmds.listRelatives(parent or target, parent=True)
        if p is None:
            stop = True
        else:
            parent = p[0]
            
           
    if parent:
        print('{} has top-level parent {}'.format(target, parent))
    else:
        print('{} is top-level object'.format(target))

Output:

Full hierarchy: |group10|group9|group8|group7|group6|group5|group4|group3|group2|group1|pCylinder1
pCylinder1 has top-level parent group10
group4 has top-level parent group10
group10 is top-level object

Edit: Looks like I didn’t read your question properly. We more or less came up with the same code, so I suppose my answer to your question is Yes, this is probably the best way.

You can also use the full path of an object and split by |, but it’s not necessarily as precise as it sounds — especially if the objects gets passed to your method by their short names.

Answered By: Daniel Skovli

Answer 2

You don’t need to go trough listRelatves at all:

if you look at the long name of some transform, for example ‘|group4|group5|group6|pCube4′, you will notice that the top nodes’ long name is already there

def Outliner_TopMost__Get_or_Select(Sel_LongNames=None, Mode='Select'):
    if Sel_LongNames is None:
        # 'o=1' will return only objects, or rather shapes, if in component mode
        Sel_LongNames=cmds.ls(sl=1,fl=1,l=1,o=1)

    finalList=[]
    for item in Sel_LongNames:
        # get the first name after '|', and add it to '|' to create the long name
        finalList.append("|"+item.split('|')[1])
    
    if Mode=='Select':
        cmds.select(finalList)
    else:
        return finalList

This function will work on Selection, or if you provide it with a list of object, but with long names (‘l’ flag in cmds.ls). It will also select the meshes, or return the selection, according to the flag ‘Mode’.

Note: will return the top node, even if it is a Mesh, rather then a transform.

Answered By: Bob

Maya python get top most parent transforms

Question:

Answers: