=General=
==Is Mutable right for my project?==
Many projects can get away with a system of interchangeable parts for their characters, and use some real time shader effects for colours. For those projects, Mutable is not necessary at all. Mutable aims more at solving the case for games like APB, Kingdom Under Fire 2 or PUBG, to put examples we know very well at Anticto, where deeper customiszation is required, and performance is critical. If you contact us and tell us more about your project, we may be able to evaluate the suitability of Mutable better.
==What does Mutable exactly offer?==
Mutable provides a completely flexible mesh customization system for UE4, with no pre-determined meshes, skeletons, textures or morphs that force you into a particular template, look or functionality. You can create the customizable mesh or character you want (doesn't even have to be a biped or an animal for that matter, you could even make customizable trees or objects) with the control parameters and degrees of freedom you want, and Mutable will create a standard and efficient UE4 skeletal mesh for you to use. These skeletal meshes can either be created in realtime in-game, or can be baked into standard assets during production in the UE4 editor. This enables you to use Mutable as another powerful art pipeline tool.
Customizable characters are created with the Mutable graph editor, which is completely integrated into the UE4 editor and very comparable to UE4's own material editor. we may be ableMutable has both a C++ and Blueprint API to evaluatecontrol the suitability of Mutable bettercharacter customization in-game.
==What is the licensing cost and how can I try it?==
We are trying to have a standalone version that we can release for people to be able to evaluate Mutable freely. It will not be really polished and optimised, but we are open to do that on demand. Regarding licensing fees, we are very flexible. Take a look at [[ /w/mutable/unreal-engine-4/getting-started/#licensing | this section ]] for the latest information. We offer a per-project per-platform licensing option, with a fee for the first platform, and an additional fees for every other platform. We are also consdering an indie-like license piggy-backing on Epic's old 5% for Unreal Engine, by adding an extra 1% on gross income for Mutable in exactly the same conditions Epic has. We would consider this for promising indie projects. In both cases dedicated support needs to be paid monthly and separately. Bug-fixing and minimal non-time-critical support will be there in any case. If you don't like these options,Please visit https://mutable.games/mutable-licensing/ we are open to suggestions.
==Does Mutable include a character library we can use in our games?==
No. Mutable is not a character library and you will still need artists to create assets for your game. Mutable will let you decide how this assets are combined into the final optimised game characters, and create parameters to customize them.
==We use a non-standard material or rendering pipeline, can we use Mutable?==
Yes. Mutable can handle any number and type of materials and textures. It doesn't have any hardcoded features for "colour", "normal", "metallic" or any material property.
==Can Mutable adapt animations?==
No. Mutable only builds meshes and textures for your static or skeletal objects, it doesn't modify animations. Mutable generates a standard UE4 skeletal mesh with a standard UE4 skeleton so that you can use the full UE4 animation system.
=Using Mutable=
==How do I set a physics asset for the characters generated by Mutable?==
By default Mutable doesn't touch it, but you can activate a flag to make it automatically use the body asset of the reference mesh in the root Customizable Object. Just call UCustomizableObjectInstance::SetReplacePhysicsAssets(true). Alternatively you can use the "Physics Asset Override" property in the skeletal mesh component.
==Can Mutable handle cloth animation?==
There are several cloth animation systems in Unreal Engine, as far as we know:
* nVidia Apex cloth: Mutable does not support it, and it will not support it. This is a method that we believe it is being phased out, and it uses opaque data in binary blobs that we cannot interact with.
* Anim Dynamics: This is the method used by Epic in Paragon. It relies on bones to deform the meshes, so it is supported without any special requirement. See https://www.youtube.com/watch?v=5h5CvZEBBWo for an overview of anim dynamics by Epic. This is the recommended method when using Mutable.
* There is a new cloth system in Unreal Engine since 4.19 (Clothing Tool). We don't have support for it yet, but it will be supported very soon.
==How Mutable handles content updates and binary differences==
All the data Mutable generates after a successful compilation of all the customizable objects in the game (typically a few hundred MBs for a complete game, which are streamed and cached in-game) is stored in a number of files in a folder inside the game project. Both the folder and the number of files can be easily changed via some configuration options. These options let the developer specify how big the files can be, so if the dev sets a really high limit, all the data will be stored in a single big file which will be modified after each content update.
Conversely, a very low size limit will pack every single object in its own small file. This will generate a ton of files, but will handle content updates more gracefully, modifying only the files that have really changed. UE4's own pak system will take on from here, with the possibility of packaging all the Mutable files in a single pack file, splitting them into several pak files or even not putting them in a pak file at all.