LookdevX scene callbacks in Maya 2025 #4313
Description
Product: Autodesk Maya 2025
Component: LookdevX
Version: ( Maya 2025.3.1)
OS: (Windows 11)
Summary
Severe performance slowdown when creating a new scene (File > New Scene) with the LookdevX plugin loaded.
The slowdown is caused by repeated global scans of materialxStack nodes during scene teardown.
Steps to Reproduce
Launch Maya 2025 (LookdevX plugin auto-loaded).
Open any scene with some geometry and materials.
Go to File > New Scene.
Observe that Maya hangs/freezes for several seconds.
Check Script Editor: it repeatedly calls
ls -type materialxStack -long
If the LookdevX plugin is unloaded before creating a new scene, the issue disappears.
Expected Result
Creating a new scene should be fast, regardless of whether LookdevX is loaded.
LookdevX should not perform unnecessary global node scans (ls -type materialxStack) on every scene switch.
Actual Result
With LookdevX loaded:
Maya freezes noticeably when creating a new scene if another scene is already open.
Script Editor shows repeated ls -type materialxStack -long calls.
With LookdevX unloaded:
Creating a new scene is instant, no slowdown.
Impact on Workflow
New/Open Scene operations are significantly slowed down in production environments.
This affects users who do not actively use MaterialX/LookdevX but still have the plugin auto-loaded.
Makes scene iteration painful in larger projects.
Workaround
Manually unloading LookdevX before creating a new scene:
import maya.cmds as cmds
if cmds.pluginInfo("lookdevX", query=True, loaded=True):
cmds.unloadPlugin("lookdevX")
This avoids the slowdown but prevents the use of LookdevX until reloaded.
Request
Please optimize LookdevX scene callbacks in Maya 2025 so that:
It does not repeatedly scan for materialxStack nodes on every scene switch, or
It only scans when MaterialX features are actively in use.