# Generate LOD Chain

> How to automatically generate a LOD chain in Asset Transformer Studio

![Generate LOD Chain](/api/media?file=/asset-transformer-studio/2026.5.0/media/ALGO_GenerateLODChain.jpg)

## Description

[Generate LOD Chain](/asset-transformer-studio/2026.5.0/api/python/process_functions.md#generatelodchain) is a ready-to-use process to automatically create LODs from a high-poly model.

Generated LODs (LOD1, LOD2…) are clones of the original high-poly model (LOD0), which are decimated (each time with stronger, more destructive values) to lower their [polycount](http://wiki.polycount.com/wiki/Polygon_Count), to be used as optimized versions for performance.

The user can choose the decimation strategy to generate the LODs, between [Decimate To Quality](../../../data-preparation-fundamentals/about-decimation/decimate-to-quality) and [Decimate To Target](../../../data-preparation-fundamentals/about-decimation/decimate-to-target).

Parts are renamed with a suffix (`\LODn`) to fit the naming convention handled by most game engines to automatically apply LOD behaviors.

> **Note:**
>
> * This scenario works for meshes only (requires the selected parts to be tessellated first).
> * More information about LODs can be found in the [Unity documentation](https://docs.unity3d.com/Manual/LevelOfDetail.html).

## How To

![Generate LOD Chain animation](/api/media?file=/asset-transformer-studio/2026.5.0/media/ALGO_GenerateLODChain3.gif)

1. Select the portion of the hierarchy for which you wish to create LODs (a group of parts or a root node).
2. Launch the [Generate LOD Chain](/asset-transformer-studio/2026.5.0/api/python/process_functions.md#generatelodchain) feature from the [Optimize Mesh](./_index.md) menu (or using the Python command in a script).
3. Choose the decimation strategy, between [Decimate To Quality](../../../data-preparation-fundamentals/about-decimation/decimate-to-quality) and [Decimate To Target](../../../data-preparation-fundamentals/about-decimation/decimate-to-target).
4. Define the number of LODs generated by adding or removing rows in the table.
5. Fine-tune the default values if necessary.
6. Click `Execute`: the process is launched and for each [part](../../../data-preparation-fundamentals/glossary) in the [Product Structure](../../../data-preparation-fundamentals/about-the-product-structure-tree) (hierarchy):
   1. A group occurrence (or [assembly occurrence](../../../data-preparation-fundamentals/about-occurrences/occurrence-types) in Asset Transformer Studio vocabulary) is created with the name of the Part.

   2. The Part is cloned in the generated group as many times as the number of LODs defined as input, with the following structure:
      * `PartName`
        * `PartName\LOD0`
        * `PartName\LOD1`
        * `PartName\LODn`

   3. Each LOD group is decimated using the chosen strategy and the input values for the LOD: all the parts of the LODn are selected and processed together.

      > **Note:**
      >
      > When the decimation strategy chosen is [Decimate To Target](../../../data-preparation-fundamentals/about-decimation/decimate-to-target), the whole selection of parts is taken into account to reach the targeted [polycount](http://wiki.polycount.com/wiki/Polygon_Count) (not each individual part's polycount will reach the desired target). More information about the algorithm behavior can be found [here](../../../data-preparation-fundamentals/about-decimation/decimate-to-target#general-behavior).

   4. The result is a hierarchy as below:

      ![LOD Chain result](/api/media?file=/asset-transformer-studio/2026.5.0/media/ALGO_GenerateLODChain2.jpg)