How do you optimize your rig for game engines?

1 Choose the right rig type

There are different types of rigs that you can use for your 3D characters, such as bone-based, blendshape-based, or hybrid rigs. Each type has its own advantages and disadvantages, depending on the complexity, style, and animation of your character. For example, bone-based rigs are more flexible and dynamic, but they can also be more CPU-intensive and harder to export. Blendshape-based rigs are more simple and compatible, but they can also be more memory-intensive and less expressive. Hybrid rigs combine both methods to balance the pros and cons, but they can also be more difficult to set up and manage. You should choose the rig type that suits your character's needs and your game engine's specifications.

2 Reduce the number of bones

One of the most common ways to optimize your rig for game engines is to reduce the number of bones in your skeleton. Bones are the basic elements of your rig that define the structure and movement of your character. However, too many bones can also increase the computational cost and the file size of your rig. To reduce the number of bones, you should remove any unnecessary or redundant bones, such as extra fingers, toes, or facial bones. You should also merge or simplify any complex or overlapping bones, such as spine, neck, or shoulder bones. You should aim to have around 50 to 100 bones for your rig, depending on your character's design and your game engine's limitations.

3 Optimize the skinning weights

Another important way to optimize your rig for game engines is to optimize the skinning weights of your mesh. Skinning weights are the values that determine how much each bone influences each vertex of your mesh. They are essential to create smooth and natural deformations of your character's skin. However, too many or too high skinning weights can also cause problems, such as distortion, clipping, or lagging. To optimize the skinning weights, you should use tools such as weight painting, smooth binding, or auto-rigging to assign and adjust the weights accurately and efficiently. You should also limit the number of bones that affect each vertex to around 4 to 8, depending on your character's resolution and your game engine's capabilities.

4 Use LODs and proxy meshes

A useful technique to optimize your rig for game engines is to use LODs and proxy meshes. LODs are levels of detail that change the quality and complexity of your rig depending on the distance and angle of the camera. They help to save resources and improve performance by reducing the number of bones, vertices, and polygons that are rendered at any given time. Proxy meshes are simplified versions of your mesh that are used for collision detection, physics simulation, or shadow casting. They help to avoid glitches and errors by using less geometry and detail than your original mesh. You can create LODs and proxy meshes by using tools such as decimation, retopology, or baking to generate lower-resolution models of your rig.

5 Test and export your rig

The final step to optimize your rig for game engines is to test and export your rig. Testing your rig is crucial to ensure that it works properly and smoothly in your game engine. You should test your rig for functionality, compatibility, and performance by using tools such as animation preview, export validation, or debug mode. You should also fix any issues or errors that you encounter, such as broken constraints, missing textures, or incorrect rotations. Exporting your rig is the process of converting your rig into a format that your game engine can read and use. You should export your rig by using tools such as export settings, file formats, or plugins to match your game engine's requirements and standards.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?