UNICA: A Unified Neural Framework for Controllable 3D Avatars

Abstract

Controllable 3D human avatars have found widespread applications in 3D games, the metaverse, and AR/VR scenarios. The conventional approach to creating such a 3D avatar requires a lengthy, intricate pipeline encompassing appearance modeling, motion planning, rigging, and physical simulation. In this paper, we introduce UNICA (UNIfied neural Controllable Avatar), a skeleton-free generative model that unifies all avatar control components into a single neural framework. Given keyboard inputs akin to video game controls, UNICA generates the next frame of a 3D avatar's geometry through an action-conditioned diffusion model operating on 2D position maps. A point transformer then maps the resulting geometry to 3D Gaussian Splatting for high-fidelity free-view rendering. Our approach naturally captures hair and loose clothing dynamics without manually designed physical simulation, and supports extra-long autoregressive generation.

Resources

• Paper: UNICA: A Unified Neural Framework for Controllable 3D Avatars
• GitHub Repository: https://github.com/zjh21/UNICA

Installation and Usage

Please refer to the official GitHub repository for detailed installation instructions and inference scripts. The pipeline generally involves two stages:

1. Geometry Generation: Using the action-conditioned diffusion model to generate position maps.
2. Appearance Mapping: Mapping geometry to 3D Gaussian Splatting via a point transformer for rendering.