How to extract smooth mesh preview curves from a mesh in Maya

Tips and tricks for anyone using Maya and Rhino for architecture 3D modeling

Overview

This is a useful script to keep handy when doing a maya-to-rhino workflow. It allows you to extract curves (even from Smooth Mesh Preview!) from the mesh, and bring it as NURBS in Rhino.

The script

import maya.cmds as cmds

objList = cmds.ls(selection=1)
edgeNum = cmds.polyEvaluate(edge=1)
edgeList = []
i=0
while i<edgeNum:
    edgeList.append(i)
    i+=1

CurveList = []
while edgeList:
    usedEdgeList=cmds.polySelect(objList[0],edgeLoop=edgeList[0])
    tmpCurveList=cmds.polyToCurve(form=3,degree=1)
    cmds.matchTransform(tmpCurveList[0],objList[0],pivots=True)
    CurveList.append(tmpCurveList[0])
    for j in usedEdgeList:
        if j in edgeList:
            edgeList.remove(j)   

for c in CurveList:
    if (c!=CurveList[0]):
        curveShapeList=cmds.pickWalk(c,direction="down",type="nodes")
        cmds.parent(curveShapeList[0],CurveList[0],relative=True,shape=True)
        cmds.delete(c)

Explanation of workflow

A screenshot of the smooth mesh in question in Maya

Let’s say I want to get the green lines that describe the smooth mesh preview out as NURBS curves. I can do that by running the…