3D Sketch Maps

About

The 3D Sketch Maps project, funded by the Swiss National Science Foundation through the Sinergia funding program, investigates 3D sketch maps from theoretical, empirical, cognitive, and technological perspectives, with a particular focus on Extended Reality (XR). Although space is inherently three-dimensional, most research on spatial knowledge still relies on two-dimensional sketches. However, in many domains—such as aviation or the understanding of complex multi-level buildings—people must reason about space in three dimensions, which cannot be adequately captured with traditional 2D methods.

The project demonstrates that virtual reality–based 3D sketching enables people to externalize their knowledge of vertically complex spaces more effectively. Unlike traditional 2D sketches, which often omit or distort vertical information, 3D sketches allow spatial relationships between objects to be represented clearly in all three dimensions. This research highlights the limitations of 2D media for studying spatial knowledge and shows how XR-based 3D visualization can provide a more complete way to capture and communicate how people mentally represent complex spaces.

Project Partners

This is joint project between the ETH Zürich and WWU Münster. Our collaborators at ETH are Prof. Martin Raubal (Principal Investigator, Chair of Geoinformatics Engineering at ETH) and Prof. Christoph Hölscher (Chair of Cognitive Science at ETH).

Understanding Horizontal and Vertical Spatial Memory in Multi-Level Buildings

Our research investigates how people remember spatial relationships in multi-level buildings, focusing on the difference between horizontal relations (within a floor) and vertical relations (across floors). Using virtual environments and VR-based 3D sketch maps, we studied how people reconstruct complex building layouts from memory.

The findings show a clear asymmetry: people remember spatial relations within a floor much more reliably than relations between floors. Vertical relationships are harder to integrate into a coherent mental map, especially when floors are structurally misaligned.

This insight is important for the design of complex environments such as hospitals, airports, or shopping centers, where navigation across multiple levels can be challenging. Understanding how people form spatial memories can help improve building design, wayfinding systems, and safety planning by emphasizing clear vertical structure and orientation cues.

Technology Innovation

Virtual reality (VR) opens new possibilities for studying the three-dimensional aspects of spatial memory. Unlike traditional paper sketches, VR allows users to directly express spatial knowledge within a 3D environment. Our partners at ETH developed VResin, a VR-based sketching interface that combines mid-air 3D drawing with 2D surface sketching in a structured, layer-by-layer workflow.

Using VResin, we extend traditional 2D sketch-map methods to 3D. The layer-based approach helps participants reconstruct complex multi-level buildings and represent spatial relationships across floors in a consistent way.