Maya Python执行polySeparate报错，新手求问原因

Hey there! Let's break down why that frustrating error is popping up when you run your Maya Python code. The message "polySeparate needs exactly 1 polygonal object or polygonal faces from one object" is Maya's way of saying: "I can only work with either a single full polygon object, or multiple faces that all belong to the same polygon object — right now, your selection doesn't fit either case."

Here's the core issue with your current code: #

Your polyChipOff command uses kft=False (turns off "keep faces together") but omits the dup=True flag. By default, polyChipOff copies your selected faces but keeps them as part of the original polygon object — it doesn't create a new, separate object automatically.

When you run polySeparate right after this, Maya gets confused:

• If your selection includes both the original faces and the copied faces (still tied to the same object), that might not trigger the error, but more likely...
• If your selection accidentally includes multiple objects (maybe you had other geometry selected before running the code) or the copied faces aren't properly isolated, polySeparate throws the error because it can't process mixed selections.

How to fix it: #

Adjust your code to explicitly tell polyChipOff to create a new object for the copied faces, then target that object for separation:

import maya.cmds as cmds

# Make sure you have faces selected before running this!
# Copy selected faces into a new, separate object
cmds.polyChipOff(ltz=0.1, kft=False, dup=True)
# Grab the newly created object (it's auto-selected after polyChipOff with dup=True)
new_isolated_faces = cmds.ls(selection=True)[0]
# Separate the individual faces into their own objects
cmds.polySeparate(new_isolated_faces)

Alternatively, if you want to keep the copied faces on the original object and just split them off:

import maya.cmds as cmds

# Copy faces onto the original object (no new object created)
cmds.polyChipOff(ltz=0.1, kft=False)
# Confirm only the copied faces are selected (polyChipOff usually selects them by default)
# Then run polySeparate on the selected faces (all belonging to one object)
cmds.polySeparate()

Quick pro tip for future Maya scripting: #

Always verify your selection before running commands like polySeparate — add a quick print statement to check what's selected:

print("Current selection:", cmds.ls(selection=True))

This helps you catch mixed or incorrect selections before they cause errors.

内容的提问来源于stack exchange，提问作者Matthew W