To address the defects of point cloud rendering, UniWorld-View proposes occlusion-aware point cloud rendering. The first step is dual projection: project the source image to the target view and then back-project to the original view; pixels that cannot 'return' are occlusion regions. These are accumulated frame by frame along the camera trajectory to form an occlusion mask, which is removed during rendering to prevent misleading textures from confusing the generative model. The second step is normal filtering: estimate a normal vector for each point, compute the angle with the viewing direction, and directly discard points facing away from the camera, solving backside light leakage.
After solving geometric issues, texture detail deficiencies remain. UniWorld-View adopts dual-stream condition injection: the geometry stream encodes the point cloud render plus mask and adds it to the latent variable, ensuring generated content aligns with 3D structure; the appearance stream uses the Ref-DiT module, performing cross-attention with novel view features as Query and source video features as Key/Value, allowing the model to 'borrow materials' from the original video to complete textures, even repairing blurry textures caused by point cloud artifacts.