WorldCompass: Reinforcement Learning for Long-Horizon World Models
Zehan Wang, Tengfei Wang, Haiyu Zhang, Xuhui Zuo, Junta Wu, Haoyuan Wang, Wenqiang Sun, Zhenwei Wang, Chenjie Cao, Hengshuang Zhao, Chunchao Guo, Zhou Zhao
TL;DR
WorldCompass introduces a post-training reinforcement learning framework tailored to long-horizon, autoregressive video-based world models. It keyly combines a clip-level rollout strategy, complementary reward functions for interaction following and visual quality, and a negative-aware fine-tuning optimization to enable efficient and robust RL training. The approach yields substantial gains in action fidelity and perceptual quality on the state-of-the-art WorldPlay model across short, medium, and long horizons, including complex compositional actions. This work demonstrates that targeted RL post-training can significantly enhance both controllability and visual realism in interactive world models, with practical training efficiency suitable for large-scale deployment.
Abstract
This work presents WorldCompass, a novel Reinforcement Learning (RL) post-training framework for the long-horizon, interactive video-based world models, enabling them to explore the world more accurately and consistently based on interaction signals. To effectively "steer" the world model's exploration, we introduce three core innovations tailored to the autoregressive video generation paradigm: 1) Clip-level rollout Strategy: We generate and evaluate multiple samples at a single target clip, which significantly boosts rollout efficiency and provides fine-grained reward signals. 2) Complementary Reward Functions: We design reward functions for both interaction-following accuracy and visual quality, which provide direct supervision and effectively suppress reward-hacking behaviors. 3) Efficient RL Algorithm: We employ the negative-aware fine-tuning strategy coupled with various efficiency optimizations to efficiently and effectively enhance model capacity. Evaluations on the SoTA open-source world model, WorldPlay, demonstrate that WorldCompass significantly improves interaction accuracy and visual fidelity across various scenarios.
