[Python] Struggling to provide a correct value to 'OpenMaya.MItMeshPolygon.center()'

Am taking first steps into the Open Maya API, the Python version. I've gone through a Maya API series, and did some tasks such as printing to the script editor. I am now trying to write my own small bits of code. In this case, trying to solve a task I recently solved through maya commands, which is get the centre of a polygon face.

I am sure, I can accomplish this with just the OpenMaya.MItMeshPolygon.center() method but am not having any success calling it. The documentation states that it is expecting a kObject as input. So with a face selected, I tried the following, which results in a error:

import maya.api.OpenMaya as om

coordValue = om.MItMeshPolygon.center(om.MSpace.kWorld)
print(coordValue) #am expecting this to give me the center of the face I have selected
#Error: TypeError: descriptor 'center' for 'OpenMaya.MItMeshPolygon' objects doesn't apply to a 'int' object


Since this kObject, just seems to consist of a integer, I also tried passing a integer directly:

import maya.api.OpenMaya as om

print(om.MSpace.kWorld) #prints 4
coordValue = om.MItMeshPolygon.center(4) #am expecting this to give me the center of the face I have selected
print(coordValue)


I have looked through the Devkit examples that Autodesk provides but have not been able to find an answer. What could I doing wrong? Am on Maya 2026.

Edit1:

Okay, after spending another hour on it and some more searching... I figured it out! well partly.

Here is my code as it stands:

import maya.api.OpenMaya as om
import maya.cmds as cmds
def get_selected_center():
selection = om.MGlobal.getActiveSelectionList()
if selection.length() == 0:
raise RuntimeError("Nothing selected")
dag_path, component = selection.getComponent(0)
if not dag_path.node().apiType() == om.MFn.kMesh:
raise RuntimeError("Selected object is not a mesh")
poly_iter = om.MItMeshPolygon(dag_path, component)

center = poly_iter.center(om.MSpace.kWorld)
return center

center = get_selected_center() # this retuns a three part array, well maybe not an array, but definetly something
cmds.spaceLocator(p=(center.x, center.y, center.z))


The only issue am facing is that the above code, will only work as I expect it to, if I have a polygon face selected. When I have a polygon face selected, the locator is created on its centre, but if I have a edge or vertex selected, the locator is still created at the centre of the face.

As shown HERE, but am looking to create the locator at the centre of a selected edge, face or at the position of a vertex.

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