PushPull++
📜 Abstract
PushPull tools are implemented in most commercial 3D modeling suites. Their purpose is to intuitively transform a face, edge, or vertex, and then to adapt the polygonal mesh locally. However, previous approaches have limitations: Some allow adjustments only when adjacent faces are orthogonal; others support slanted surfaces but never create new details. Moreover, self-intersections and edge-collapses during editing are either ignored or work only partially for solid geometry. To overcome these limitations, we introduce the PushPull++ tool for rapid polygonal modeling. In our solution, we contribute novel methods for adaptive face insertion, adjacent face updates, edge collapse handling, and an intuitive user interface that automatically proposes useful drag directions. We show that PushPull++ reduces the complexity of common modeling tasks by up to an order of magnitude when compared with existing tools.
✨ Summary
Paper summary
PushPull++ presents a local mesh-editing method for rapid modeling of plane-dominant, man-made objects. The method transforms a selected face to a target plane and adaptively decides whether neighboring geometry should be modified or whether new faces should be inserted. It maintains planar polygonal faces by computing new vertex positions from plane intersections and updating the affected one-ring neighborhood, including cases where vertex valence changes.
The paper also introduces stepwise modification for handling local self-intersections, shrinking edges, and collapsing faces without relying on watertight solids or constructive solid geometry. Multiple faces can be modified simultaneously, provided that inserted faces use a consistent global direction. The associated interface proposes useful drag directions, supports face, edge, and vertex operations, and combines push-pull editing with polyline-based face splitting.
In an expert-user evaluation covering fifteen modeling operations, the authors report that PushPull++ required fewer interactions than AutoCAD, SketchUp, and Maya on average, particularly for edits involving slanted surfaces and added details. The implementation was reported to support interactive editing at at least 30 updates per second on mainstream hardware. (peterwonka.net)
Documented influence
A concrete later use appears in research on semantically enriched high-resolution LoD3 building-model generation. That work describes PushPull++ as suitable for efficient LoD3 modeling and reports using an implementation derived from Esri CityEngine for interactive geometry modification. This provides evidence of application in architectural and urban-modeling workflows, although the available search results do not establish broader adoption or a large body of follow-up methods directly extending the algorithm. (researchgate.net)