Why do certain interfaces feel effortless while others feel exhausting? This paper proposes Timelines and Topographies as a conceptual framework to answer this question, reinterpreting interface design through the lens of human attention. We distinguish between timelines—a linear mode where the system serializes information to offload the cognitive cost of attentional control (e.g., social media feeds)—and topographies—a spatial mode where the system’s structural relations are directly presented to the user (e.g., folder hierarchies, canvas UIs). We apply this framework to analyze a wide spectrum of interfaces, ranging from classic desktop metaphors to modern Personal Information Management tools like Slack and Notion. Furthermore, we identify Large Language Models as bidirectional translators that bridge these modes by converting complex topographic structures into conversational timelines, and vice versa. Finally, we provide design guidelines for harnessing both modes, enabling interfaces that support fluid transitions between subjective timelines and objective topographies.

Dexterous freehand manipulation in virtual reality offers rich interaction but is limited by physical reach. Existing indirect remote manipulation techniques often sacrifice this dexterity. We address this by defining “virtually direct” manipulation, a conceptual framework for techniques that break from a purely direct or indirect model by decoupling the virtual hand from the physical one. Within this framework, we present Hitchhiking Hands (HH), a novel implementation designed to preserve the rich dexterity of direct manipulation at a distance. HH allows users to instantly switch control between multiple pre-defined virtual hands using gaze. We evaluated HH in two user studies. A first study showed our approach, which consistently maintains direct-touch properties, surpasses an established baseline in 6DoF manipulation performance and embodiment. A second qualitative study revealed HH excels in structured spaces but is ill-suited for unstructured global tasks, highlighting a trade-off between flexibility and learnability.

Presenting haptic feedback in virtual reality (VR) is a long-standing challenge, with passive haptics being one way of presenting haptic feedback inexpensively. However, passive haptics requires props in physical environments that are co-located with their virtual counterparts, which is often not the case in the real world. Although redirected hands and other methods have previously been proposed to solve this problem, significant differences between the displayed and actual hand positions can cause the degradation of presence and sense of embodiment, limiting the range of presentable environments. In this study, we present a new hand displacement method called wormholes, in which the virtual hand is teleported discontinuously as the user inserts their hand into the hole. The experiment showed that the wormhole could maintain the sense of embodiment, presence, and task performance even with large hand displacements. Our method enables to apply passive haptics even when the actual and virtual environments are quite different, contributing to the realization of inexpensive and flexible haptic presentation in VR applications.