Maya polygon smooth algorithm

maya_polygon_smooth_algorithm.py

'''
Simple PyMel smooth (NOT subdivide) algorithm

A simple example of a smooth algorithm in PyMel. This is NOT fast or optimized!
The math behind it is as follows: 
 - The new position of a vertex is the average of its position and all positions of its connected vertices.
 - The weight of original position of the vertex is the same as the number of connected vertices.
'''
import pymel.core as pm

# Select some verticies on an poly object for this to run
vertices = pm.ls(selection=True, flatten=True)
finalPositions = []

for vertex in vertices:
    numConVerts = len(vertex.connectedVertices().indices())
    position = vertex.getPosition(space="world") * numConVerts

    for conVert in vertex.connectedVertices():
        position += conVert.getPosition(space="world")
        numConVerts += 1

    finalPositions.append(position / numConVerts)

for vertex, position in zip(vertices, finalPositions):
    vertex.setPosition(position, space="world")