About Level of Detail Migration

Level of Detail representations were introduced to improve capacity and performance when computers were slower and had less memory. Assemblies containing LOD's and substitutes are converted to Model States in Inventor 2022 or newer.

Level of Detail conversion

When you open a legacy assembly containing LODs, the following system-defined LODs are removed:

• All Components Suppressed
• All Parts Suppressed
• All Content Center Suppressed

The Master LOD and all user-defined LODs, including substitutes, are retained and converted to Model States.

Hide Content Center Components is added to the Design View File Open options to provide functionality similar to the legacy All Content Center Suppressed LOD.

In the following image, the Master LOD is converted to the Primary model state. The user-defined LOD, and the Substitute LOD are converted to Model States with the same name. The three system-defined LODs that suppressed All Components, All Parts, and All Content Center are removed.

Tip: You can use View Representations in place of legacy LODs to achieve similar large assembly performance improvements. Invisible components are not loaded into memory.

In previous releases, a Bill of Materials or Parts List created from an LOD referenced the Master LOD which contained all components. A Bill of Materials in a non-master migrated LOD still uses the Bill of Materials defined by Master. This condition is referred to as a delegated Bill of Materials. A message about BOM delegation appears when you create a Bill of Materials from a migrated user-defined LOD or substitute.

What is BOM delegation?The BOM delegation message box appears when you start the Bill of Materials or Parts List command to alert you when the information source is a different model state. The BOM delegation message appears if the active model state meets one of the following conditions:

• The model state is a migrated non-Master Level of Detail.
• The model state is a substitute part file.

Click Yes to activate the source model state and display the BOM.

Tip: You cannot edit the BOM of a migrated non-master LOD or a substitute. If you want to edit the BOM of a Model State created from a non-master LOD, create a copy of the model state. Optionally, keep the editable new copy and delete the migrated model state.