HyBoDT: Hybrid Bounded Distance Transforms of Trimmed NURBS Models

Distance field representation of objects in 3D space has several applications such as shape manipulation, graphics rendering, path planning, etc. Distance transforms (DTs) are discrete representations of distance fields in a regular voxel grid. The two main limitations of using distance transforms are that they are compute-intensive, and there are errors introduced while representing the object using DTs. In this work, we develop an hybrid GPU-accelerated marching wavefront method for computing DTs of models composed of trimmed NURBS surfaces with theoretical bounds. Our hybrid marching approach eliminates the error due to calculating approximate distances by marching. We also calculate the bounds on the error introduced due to the tessellation of the trimmed NURBS surfaces and calculate the propagation of these bounds in computing the DT. Finally, we present computation times for both 2D and 3D GPU DTs of test objects. We show that our GPU-accelerated approach is significantly faster than existing CPU-based methods.

Influence of Digital Media Technology on Forest Scene Animation Design

The animation construction of forest scene is a virtual stand scene visualization framework which uses the related technologies of virtual forest modeling and stand scene visualization, and uses the scene graph technology to manage. This paper studies the influence of digital media technology on the animation design of forest scene. In this paper, the model of virtual stand scene is mainly completed by Creator modeling software of MultiGen company. In order to reduce the number of scene patches and ensure realism, the tree model is designed with OpenFlight tree hierarchy. At the same time, the key technologies of Creator modeling and model optimization are analyzed. The virtual stand scene visualization framework uses the open source graphics rendering engine OpenSceneGraph (OSG) as the scene driver to realize the stand scene visualization. This paper provides a variety of roaming control methods. The experimental results show that the virtual forest scene visualization framework can better simulate the forest scene and has a strong sense of reality.

Construction of English Classroom Situational Teaching Mode Based on Digital Twin Technology

In order to improve the effect of English classroom teaching, this paper combines the digital twin technology to construct the English classroom situational teaching mode. The system uses advanced virtual reality technology and computer image technology, and combines with video and audio synchronization processing technology to provide a new set of methods for students' language learning. The graphics rendering server of the scene interactive teaching system renders and generates 3D virtual scenes or real images in real time. Moreover, this paper constructs the functional modules of the situational teaching system according to the English classroom teaching situation, and conducts an in-depth analysis of the system implementation methods, expresses the system core algorithm flow in the form of diagrams and tables, and obtains the overall system framework. Finally, this paper evaluates the effect of the English classroom situational teaching model proposed in this paper through experimental research. From the experimental results, it can be seen that the teaching model proposed in this paper is very effective.

Virtual Reality Design and Realization of Interactive Garden Landscape

It is very important to study and explore the application of virtual reality technology in landscape garden design, especially in the current environment of triple network integration and Internet of Things construction, to promote and facilitate the rapid development of digital landscape garden design in China. In this paper, we study the implementation method of virtual landscape gardening system and establish a virtual environment based on the ancient city of Yangcheng. On the computer platform, we study and realize a virtual roaming system of medium complexity with more complete roaming functions. Using the Quest3D software platform, a desktop-type virtual garden simulation system was developed, focusing on the virtual reality modeling technology method and virtual system implementation. The experimental results show that the GPU-accelerated drawing method based on GLSL can significantly improve the drawing frame rate of 3D garden landscape vegetation scenes with a small amount of scene data and has a certain feasibility. Based on the OpenSceneGraph (OSG) graphics rendering engine, the visualization of various types of 3D landscape models is realized, and the spatial layout of various types of landscape with parametric control is realized through digital vector layers, which flexibly manage and organize various garden elements and reasonably organize the spatial topological relationship between various types of landscape in 3D space. By integrating cross-platform ArcGISEngine components, the basic data of garden scenes including terrain data and vector data are managed. Through scene view cropping and hierarchical detail modeling technologies, the drawing efficiency and rendering real time of the garden landscape are improved. It realizes interactive 3D scene browsing and provides a six-degree-of-freedom all-round display of the overall landscape.

Measuring Key Quality Indicators in Cloud Gaming: Framework and Assessment Over Wireless Networks

Cloud Gaming is a cutting-edge paradigm in the video game provision where the graphics rendering and logic are computed in the cloud. This allows a user’s thin client systems with much more limited capabilities to offer a comparable experience with traditional local and online gaming but using reduced hardware requirements. In contrast, this approach stresses the communication networks between the client and the cloud. In this context, it is necessary to know how to configure the network in order to provide service with the best quality. To that end, the present work defines a novel framework for Cloud Gaming performance evaluation. This system is implemented in a real testbed and evaluates the Cloud Gaming approach for different transport networks (Ethernet, WiFi, and LTE (Long Term Evolution)) and scenarios, automating the acquisition of the gaming metrics. From this, the impact on the overall gaming experience is analyzed identifying the main parameters involved in its performance. Hence, the future lines for Cloud Gaming QoE-based (Quality of Experience) optimization are established, this way being of configuration, a trendy paradigm in the new-generation networks, such as 4G and 5G (Fourth and Fifth Generation of Mobile Networks).

The Real-Time Rendering of Gradient Media

In the real world, there are optical media that are difficult or impossible to simulate with classical real-time rendering methods. One of such media types is a gradient medium, in which light rays propagate along a curve. However, with advances in the capabilities of the real-time computer graphics rendering hardware, more sophisticated rendering algorithms, e.g., rendering based on the ray tracing technologies which uses a physically correct model of the light propagation and transformation, are becoming more widely used to achieve more realistic images. In the scope of the current article, the authors researched the capabilities of the current accelerated ray tracing-based realistic rendering technologies to perform the physically correct rendering of scenes containing the gradient medium. The presented method can operate in realtime which was proven by presenting the test images and aminations acquired from the implementation of the designed realistic rendering method of the gradient media with NVIDIA OptiX.