让用户用文字控制3D物体运动，精准融入高质量3D场景。

We introduce Drag4D, an interactive framework that integrates object motion control within text-driven 3D scene generation. This framework enables users to define 3D trajectories for the 3D objects generated from a single image, seamlessly integrating them into a high-quality 3D background. Our Drag4D pipeline consists of three stages. First, we enhance text-to-3D background generation by applying 2D Gaussian Splatting with panoramic images and inpainted novel views, resulting in dense and visually complete 3D reconstructions. In the second stage, given a reference image of the target object, we introduce a 3D copy-and-paste approach: the target instance is extracted in a full 3D mesh using an off-the-shelf image-to-3D model and seamlessly composited into the generated 3D scene. The object mesh is then positioned within the 3D scene via our physics-aware object position learning, ensuring precise spatial alignment. Lastly, the spatially aligned object is temporally animated along a user-defined 3D trajectory. To mitigate motion hallucination and ensure view-consistent temporal alignment, we develop a part-augmented, motion-conditioned video diffusion model that processes multiview image pairs together with their projected 2D trajectories. We demonstrate the effectiveness of our unified architecture through evaluations at each stage and in the final results, showcasing the harmonized alignment of user-controlled object motion within a high-quality 3D background.