ActiveStructure: Plane Scene Graph-Guided Active 3D Gaussian Splatting

Active 3D Gaussian Splatting methods select views usingfactorised per-pixel metrics, which cannot represent relationships be-tween surfaces. Incompleteness that arises from unverified geometric re-lationships therefore goes undetected. We present ActiveStructure,which lifts information gain from pixels to scene-level relational topol-ogy through three innovations: (1) a Plane Scene Graph whose topolog-ical health, captured through node connectivity, edge completeness, andangular consistency, quantifies a form of structural completeness thatno pixel-level criterion can reach; (2) a gain decomposition that splitsthe value of a viewpoint into a rendering-fidelity term and a structural-integrity term that can be optimised independently; (3) informationalpolarity reversal, which lets scaffold planes switch from exploration at-tractors to suppressors and provides state-driven phase control tied tostructural objectives. Experiments on Replica and Matterport3D demon-strate state-of-the-art reconstruction accuracy and rendering quality.