Basic Concepts

Resources, assets and actors

The following diagram shows the elements involved in a project with customizable objects using Mutable:

New asset types

Mutable for Unreal Engine 4 brings two new type of assets to the engine.

Customizable Object

This asset represents an object that can be customized. It includes all the possible variations that can be applied, and defines the parameters that can be controlled at run-time (by the player, or by game code), and how they affect the final objects.

There is a special tool calle Customizable Object Editor inside the Unreal Editor to show and edit this kind of asset. It looks like this:

Customizable Object Instance

This asset represents an instance of a CustomizableObject, so it is a “customized object”. It simply contains a set of values for the parameters of an object. It can be used by game actors to create their in-game meshes and materials.

Again, there is a special tool to handle these assets in the Unreal Editor: