ID 349451 - Poor performance when altering the Shader Tree in this scene (CAD scene).

TP ID: https://foundry.tpondemand.com/entity/349451-poor-performance-when-altering-the-shader

Problem summary
Altering the Shader Tree of the attached scene file (i.e moving a material layer) when a 3D Viewport view is visible causes Modo to lag.

Customer reported version
modo.12.0v1

Customer reported platform
windows7

Reproduced by support
This bug has been reproduced in:
Windows 10:
12.1v1 Beta 4
12.0v1
11.2v3
11.0v3

macOS 10.13
12.1v1 Beta 4
11.0v3

Earliest version tested
Modo 11.0v3 - This issue appears to be in all versions of the product

Expected behaviour
Faster processing when altering the Shader Tree for CAD scenes.

Actual behaviour
Poor performance (application lag) when altering the scene's Shader Tree if the 3D Viewport is visible.

Steps to reproduce

Steps to reproduce

1) Open the attached scene file "ticket37075.lxo".

2) Switch to the Shader Tree tab, and move the material layer in the material group "Rock" to the material group "rock_small". Modo will lag while trying to update the scene.

3) Remove the 3D Viewport view from the layout. You can do this by using the widget in the top right corner of the 3D Viewport, and changing the view to a basic palette (i.e. Item properties).

4) Repeat step 2. Modo does not lag when updating the change to the Shader Tree.

Workaround

Hide the 3D Viewport.