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This paper outlines a digital workflow that allows artists to add visual detail to 3D models whilst adhering to the strict polygonal budget that is vital to successfully render in real-time. Two versions of a model – a high-poly model, and a low-poly model – are produced to create a 2D normal map through a process known as ‘baking’, to achieve the illusion of the high resolution detail on the low-resolution model. [ABSTRACT FROM PUBLISHER]

In the field of geographic information, fast surface modelling techniques are important. Usually, mesh model is used to describe the terrain. However, the large data of mesh model are a bottleneck of real-time rendering. Compared with the CPU, GPU has more execution units and memory units, which greatly improves its computing capacity and memory bandwidth. Meanwhile, in the field of image rendering, OpenGL has always played an important role. Since CUDA (compute unified device architecture) and OpenGL both run on GPU and share data through common memory, this paper gives a three-dimensional terrain real-time rendering method based on CUDA–OpenGL interoperability. First, we use CUDA C kernel function to calculate the vertex coordinates and normal vectors, then we pass the data to OpenGL buffer, and render it. In this paper, we use share memory and register, overlap strategy, the expansion of concurrency and the reasonable block size. The experimental results show that this algorithm can improve the computing speed greatly, with the speedup to 212.3x, meeting the needs of real-time rendering. [ABSTRACT FROM PUBLISHER]

In economy, society and personal life map-based interactive geospatial visualization becomes a natural element of a growing number of applications and systems. The visualization of 3D geospatial information, however, raises the question how to represent the information in an effective way. Considerable research has been done in technology-driven directions in the fields of cartography and computer graphics (e.g., design principles, visualization techniques). Here, non-photorealistic rendering (NPR) represents a promising visualization category - situated between both fields - that offers a large number of degrees for the cartography-oriented visual design of complex 2D and 3D geospatial information for a given application context. Still today, however, specifications and techniques for mapping cartographic design principles to the state-of-the-art rendering pipeline of 3D computer graphics remain to be explored. This paper revisits cartographic design principles for 3D geospatial visualization and introduces an extended 3D semiotic model that complies with the general, interactive visualization pipeline. Based on this model, we propose NPR techniques to interactively synthesize cartographic renditions of basic feature types, such as terrain, water, and buildings. In particular, it includes a novel iconification concept to seamlessly interpolate between photorealistic and cartographic representations of 3D landmarks. Our work concludes with a discussion of open challenges in this field of research, including topics, such as user interaction and evaluation. [ABSTRACT FROM AUTHOR]

One of the problems in virtual globes technologies is the real-time representation of vegetal species. In forest or garden representations, the low detailed plants produce a lack of realism. Efficient techniques are required to achieve accurate interactive visualisation due to the great number of polygons the vegetal species have. This article presents a multi-resolution model based on a geometric representation of vegetal species that allows the application to perform the progressive transmission of the model, that is, the transmission of a simple representation followed by successive refinements of it. It has a hardware-oriented design in order to obtain interactive frame rates. The geometric data of the objects are stored in the graphics processing unit and, moreover, the change from one approximation to another is obtained by performing mathematical calculations in this graphics hardware. The multi-resolution model presented here enables instancing: as many vegetal species as desired can be rendered with different levels of detail, while all of them are accessing the same geometric data. This model has been used to build a real-time representation of a not imaginary scenario. [ABSTRACT FROM AUTHOR]

Modern handheld devices can act as “magic lenses” for public displays and enable camera-based real-time interaction with their contents, thus allowing for manifold interactive applications in public space. To learn more about the characteristics of common techniques and to provide guidelines for new ones, a comparative user study was conducted. With regard to two basic task types (selection and translation) and two typical devices (smartphone and tablet), three interaction techniques in-depth were evaluated: direct touch-based input (Touch), cross-hair targeting (Target), and a new technique based on a dynamic cross-hair on the screen that snaps to visible nearby screen objects (Snap Target). The study results indicate that successful interaction with the Touch technique strongly depends on the usage context: Although Touch enables fast selection, it incurs many errors when small targets have to be selected on a smartphone. Target supports such difficult selections better, but Snap Target proved to be most robust in both investigated task types. Also, users stated that they felt best supported by the latter technique. Cross-hair-based techniques, especially Snap Target, were found to be well suitable for scenarios where several device types need to be supported under similar conditions. Implications and further work are discussed. [ABSTRACT FROM PUBLISHER]