Asset management with Asset Transformer Toolkit

The Asset Transformer Toolkit functions both as an importer and an authoring tool, capable of generating, modifying, and occasionally deleting data from your project. It is crucial for users to understand how data is managed when using the Asset Transformer Toolkit. This page is designed to offer comprehensive information to ensure optimal working conditions.

We strongly recommend working in a versioned project using Unity Version Control to ensure robust version control, facilitate team collaboration, and safeguard your project's progress with comprehensive change tracking and rollback capabilities.

[!NOTE] Why opt for Unity Version Control instead of Git? Unity Version Control offers native support for large files and direct integration inside Unity Editor.

Prerequisites

Before working with this package, it is essential to be familiar with the following concepts:

Import and re-import

Import

Upon import, Asset Transformer Toolkit will generate prefabs. By default, the imported assets (such as meshes and materials) will be serialized (or saved) within their corresponding prefab, and these will be referred to as sub-assets. This method has the advantage of generating only one .prefab file on your disk.

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However, sub-assets are challenging to rename or reference in other contexts. If you need to utilize these assets elsewhere, you can modify the Save assets in setting within the project settings to Folder. This setting will save all assets as separate files in a folder adjacent to the corresponding prefab. This approach can be convenient in specific scenarios (renaming, asset referencing, editing in external tool, avoiding large prefab sizes...), but may also lead to an inflated project asset database in many cases.

Re-import

Upon re-import, Asset Transformer Toolkit will only update the prefab content below the root GameObject. This ensures that all references to the prefab asset, such as instantiations in scenes, are preserved.

However, previously imported and generated assets (such as meshes and materials) will be deleted and replaced by the new imported assets (see the Asset updates section).

Post import edition

When modifying GameObjects using the Toolbox, the Rule Engine or the LOD Generator, existing serialized assets won't be modified but new assets will be generated. This is important for faster iteration: new data is not written to disk immediately.

New assets will be considered volatile (meaning only existing in the current context) until the Prefab overrides are applied and saved to disk.

Context can be:

  • Editing a prefab via an instance: modifications will only affect this particular prefab inside this particular scene. In order to apply the modification (overrides) you need to select the modified root prefab instance, open the overrides and apply them.
  • Editing in Prefab Mode: modifications will be applied when leaving the prefab stage (and saving).
Note

If modifications are done on a GameObject not part of any prefab, the generated assets will stay serialized in the Scene.

Asset updates

Upon modifications application (via prefab saving or re-import), Asset Transformer Toolkit will automatically detect new assets and serialize them. By default, it will also delete old sub-assets and assets in adjacent folders if not used by the prefab anymore. Beware, this is a destructive process and might delete assets that are referenced elsewhere in your project. If you want to change this behaviour you can change the Save Volatile Assets project setting.

Note

In the case of a prefab modification, this post process will also detect volatile assets that were not generated by Asset Transformer Toolkit. See also Edit prefabs.

Textures

Textures can be saved as Unity assets (.asset) or as PNG files (default). Choose between the two options using the Save textures as project setting. PNG files let you access importer settings such as mipmap generation, compression quality. .png files cannot be serialized as sub-assets hence will always be serialized in an adjacent folder regardless of the Save assets in project settings.

Additional resources