Toward General Purpose 3D User Interfaces: Extending Windowing Systems to Three Dimensions

Recent growth in the commercial availability of consumer grade 3D user interface devices like the Microsoft Kinect and the Oculus Rift, coupled with the broad availability of high performance 3D graphics hardware, has put high quality 3D user interfaces firmly within the reach of consumer markets for the first time ever. However, these devices require custom integration with every application which wishes to use them, seriously limiting application support, and there is no established mechanism for multiple applications to use the same 3D interface hardware simultaneously. This thesis proposes that these problems can be solved in the same way that the same problems were solved for 2D interfaces: by abstracting the input hardware behind input primitives provided by the windowing system and compositing the output of applications within the windowing system before displaying it. To demonstrate the feasibility of this approach this thesis also presents a novel Wayland compositor which allows clients to create 3D interface contexts within a 3D interface space in the same way that traditional windowing systems allow applications to create 2D interface contexts (windows) within a 2D interface space (the desktop), as well as allowing unmodified 2D Wayland clients to window into the same 3D interface space and receive standard 2D input events. This implementation demonstrates the ability of consumer 3D interface hardware to support a 3D windowing system, the ability of this 3D windowing system to support applications with compelling 3D interfaces, the ability of this style of windowing system to be built on top of existing hardware accelerated graphics and windowing infrastructure, and the ability of such a windowing system to support unmodified 2D interface applications windowing into the same 3D windowing space as the 3D interface applications. This means that application developers could create compelling 3D interfaces with no knowledge of the hardware that supports them, that new hardware could be introduced without needing to integrate it with individual applications, and that users could mix whatever 2D and 3D applications they wish in an immersive 3D interface space regardless of the details of the underlying hardware

Magnetism and superconductivity at LAO/STO-interfaces: the role of Ti 3d interface electrons

Ferromagnetism and superconductivity are in most cases adverse. However, recent experiments reveal that they coexist at interfaces of LaAlO3 and SrTiO3. We analyze the magnetic state within density functional theory and provide evidence that magnetism is not an intrinsic property of the two-dimensional electron liquid at the interface. We demonstrate that the robust ferromagnetic state is induced by the oxygen vacancies in SrTiO3- or in the LaAlO3-layer. This allows for the notion that areas with increased density of oxygen vacancies produce ferromagnetic puddles and account for the previous observation of a superparamagnetic behavior in the superconducting state.Comment: 5 pages, 4 figures, to appear in Physical Review B (Rapid Communications

Modular 3D Interface Design for Accessible VR Applications

Designed with an accessible first design approach, the presented paper describes how exploiting humans proprioception ability in 3D space can result in a more natural interaction experience when using a 3D graphical user interface in a virtual environment. The modularity of the designed interface empowers the user to decide where they want to place interface elements in 3D space allowing for a highly customizable experience, both in the context of the player and the virtual space. Drawing inspiration from todays tangible interfaces used, such as those in aircraft cockpits, a modular interface is presented taking advantage of our natural understanding of interacting with 3D objects and exploiting capabilities that otherwise have not been used in 2D interaction. Additionally, the designed interface supports multimodal input mechanisms which also demonstrates the opportunity for the design to cross over to augmented reality applications. A focus group study was completed to better understand the usability and constraints of the designed 3D GUI.Comment: This preprint has not undergone peer review or any post-submission corrections. The Version of Record of this contribution will be published in Springer Nature Computer Science book series in Volume HCI International 202

Visualization techniques to aid in the analysis of multi-spectral astrophysical data sets

This report describes our project activities for the period Sep. 1991 - Oct. 1992. Our activities included stabilizing the software system STAR, porting STAR to IDL/widgets (improved user interface), targeting new visualization techniques for multi-dimensional data visualization (emphasizing 3D visualization), and exploring leading-edge 3D interface devices. During the past project year we emphasized high-end visualization techniques, by exploring new tools offered by state-of-the-art visualization software (such as AVS3 and IDL4/widgets), by experimenting with tools still under research at the Department of Computer Science (e.g., use of glyphs for multidimensional data visualization), and by researching current 3D input/output devices as they could be used to explore 3D astrophysical data. As always, any project activity is driven by the need to interpret astrophysical data more effectively

The use of non-intrusive user logging to capture engineering rationale, knowledge and intent during the product life cycle

Within the context of Life Cycle Engineering it is important that structured engineering information and knowledge are captured at all phases of the product life cycle for future reference. This is especially the case for long life cycle projects which see a large number of engineering decisions made at the early to mid-stages of a product's life cycle that are needed to inform engineering decisions later on in the process. A key aspect of technology management will be the capturing of knowledge through out the product life cycle. Numerous attempts have been made to apply knowledge capture techniques to formalise engineering decision rationale and processes; however, these tend to be associated with substantial overheads on the engineer and the company through cognitive process interruptions and additional costs/time. Indeed, when life cycle deadlines come closer these capturing techniques are abandoned due the need to produce a final solution. This paper describes work carried out for non-intrusively capturing and formalising product life cycle knowledge by demonstrating the automated capture of engineering processes/rationale using user logging via an immersive virtual reality system for cable harness design and assembly planning. Associated post-experimental analyses are described which demonstrate the formalisation of structured design processes and decision representations in the form of IDEF diagrams and structured engineering change information. Potential future research directions involving more thorough logging of users are also outlined

An Introduction to 3D User Interface Design

3D user interface design is a critical component of any virtual environment (VE) application. In this paper, we present a broad overview of three-dimensional (3D) interaction and user interfaces. We discuss the effect of common VE hardware devices on user interaction, as well as interaction techniques for generic 3D tasks and the use of traditional two-dimensional interaction styles in 3D environments. We divide most user interaction tasks into three categories: navigation, selection/manipulation, and system control. Throughout the paper, our focus is on presenting not only the available techniques, but also practical guidelines for 3D interaction design and widely held myths. Finally, we briefly discuss two approaches to 3D interaction design, and some example applications with complex 3D interaction requirements. We also present an annotated online bibliography as a reference companion to this article

Node-to-segment and node-to-surface interface finite elements for fracture mechanics

The topologies of existing interface elements used to discretize cohesive cracks are such that they can be used to compute the relative displacements (displacement discontinuities) of two opposing segments (in 2D) or of two opposing facets (in 3D) belonging to the opposite crack faces and enforce the cohesive traction-separation relation. In the present work we propose a novel type of interface element for fracture mechanics sharing some analogies with the node-to-segment (in 2D) and with the node-to-surface (in 3D) contact elements. The displacement gap of a node belonging to the finite element discretization of one crack face with respect to its projected point on the opposite face is used to determine the cohesive tractions, the residual vector and its consistent linearization for an implicit solution scheme. The following advantages with respect to classical interface finite elements are demonstrated: (i) non-matching finite element discretizations of the opposite crack faces is possible; (ii) easy modelling of cohesive cracks with non-propagating crack tips; (iii) the internal rotational equilibrium of the interface element is assured. Detailed examples are provided to show the usefulness of the proposed approach in nonlinear fracture mechanics problems.Comment: 37 pages, 17 figure

A software vision to enable the holistic design of low carbon buildings

The need to reduce the energy used by buildings and the resultant carbon emissions is changing how they are designed, look and work. This position paper outlines the urgent need for new software that integrates thermal simulation with building information modelling. A vision for the software is presented