A survey of real-time rendering on Web3D application

Background In recent years, with the rapid development of mobile Internet and Web3D technologies, a large number of web-based online 3D visualization applications have emerged. Web3D applications, including Web3D online tourism, Web3D online architecture, Web3D online education environment, Web3D online medical care, and Web3D online shopping are examples of these applications that leverage 3D rendering on the web. These applications have pushed the boundaries of traditional web applications that use text, sound, image, video, and 2D animation as their main communication media, and resorted to 3D virtual scenes as the main interaction object, enabling a user experience that delivers a strong sense of immersion. This paper approached the emerging Web3D applications that generate stronger impacts on people's lives through “real-time rendering technology”, which is the core technology of Web3D. This paper discusses all the major 3D graphics APIs of Web3D and the well-known Web3D engines at home and abroad and classify the real-time rendering frameworks of Web3D applications into different categories. Results Finally, this study analyzed the specific demand posed by different fields to Web3D applications by referring to the representative Web3D applications in each particular field. Conclusions Our survey results show that Web3D applications based on real-time rendering have in-depth sectors of society and even family, which is a trend that has influence on every line of industry.

Real-Time Object Detection and Face Recognition Application for the Visually Impaired

The advancement of navigation systems for the visually impaired has significantly enhanced their mobility by mitigating the risk of encountering obstacles and guiding them along safe,navigable routes.Traditional approaches primarily focus on broad applications such as wayfinding,obstacle detection,and fall prevention.However,there is a notable discrepancy in applying these technologies to more specific scenarios,like identifying distinct food crop types or recognizing faces.This study proposes a real-time application designed for visually impaired individuals,aiming to bridge this research-application gap.It introduces a system capable of detecting 20 different food crop types and recognizing faces with impressive accuracies of 83.27%and 95.64%,respectively.These results represent a significant contribution to the field of assistive technologies,providing visually impaired users with detailed and relevant information about their surroundings,thereby enhancing their mobility and ensuring their safety.Additionally,it addresses the vital aspects of social engagements,acknowledging the challenges faced by visually impaired individuals in recognizing acquaintances without auditory or tactile signals,and highlights recent developments in prototype systems aimed at assisting with face recognition tasks.This comprehensive approach not only promises enhanced navigational aids but also aims to enrich the social well-being and safety of visually impaired communities.

Real-Time Rendering of Large-Scale Ocean Environments

Simulation and rendering of large-scale natural environments, especially the ocean, has always been one of the hot issues in computer graphics, which can provide realism for various applications such as computer game, movie and military usage. Simulation of ocean environment is often lack of realism for real-time application due to its complexity of dynamic waves. In this paper, a method based on FFT Wave model is proposed to solve this problem, which can also simulate the ocean optic property with atmosphere scattering. Furthermore, our method has a lot of advantages including global ocean dataset support, real-time, dynamic reflection of ocean, the foam on the wave, smooth transition from deep ocean to seacoast, etc. The experimental results demonstrate the realism and effectiveness of our approach.

Real-Time Rendering of Dynamic Clouds Using Multi-Resolution Adaptive Grids

The multi-resolution adaptive grids method is proposed to solve the problems of inefficiency in the previous grid-based methods,and it can be used in clouds simulation as well as the interactive simulation between objects and clouds.Oriented bounding box(OBB)hierarchical trees of objects are established,and the resolutions of global and local grids can be selected automatically.The motion equations of fluid dynamics are simplified.Upwind difference is applied to ensure the stability of the simulation process during the discrete process of partial differential equations.To solve the speed problem of existed phase functions,the improved phase function is applied to the illumination calculation of clouds.Experimental results show that the proposed methods can promote the simulation efficiency and meet the need for the simulation of large-scale clouds scene.Real-time rendering of clouds and the interaction between clouds and objects have been realized without preprocessing stage.

Transmission Considerations with QoS Support to Deliver Real-Time Distributed Speech Recognition Applications

Distributed speech recognition (DSR) applications have certain QoS (Quality of service) requirements in terms of latency, packet loss rate, etc. To deliver quality guaranteed DSR application over wirelined or wireless links, some QoS mechanisms should be provided. We put forward a RTP/RSVP transmission scheme with DSR-specific payload and QoS parameters by modifying the present WAP protocol stack. The simulation result shows that this scheme will provide adequate network bandwidth to keep the real-time transport of DSR data over either wirelined or wireless channels.

Real-Time Computer Analytical Application in Pressure Transient Analysis of Petroleum Reservoirs

Today with certainty, the petroleum industry is fostering sanguinely the fields’ development programs for the optimization of reservoir characterization through worth-full appliances of computer analysis techniques. The time element is of prime importance for optimistic petroleum development projects. Therefore, the frontline of “Real-time Analysis” is added into the applications of computer solving techniques for achieving and sketching up the real-time cost effectiveness in analyzing field development programs. It focuses on the phases of real-time well test data acquisition system, real-time secure access to the well test data either on field or in office and real-time data interpretation unit. This interface will yield the productive results for the field of reservoir’s pressure transient analysis and wells’ systems analysis by following the up-to-date preferred, accurate and effective well test analytical principles with modern real-time computer applications and techniques. It also lays emphasis for the comfort and reliability of data in creating best interpersonal working modes within a reputable and esteemed petroleum development organization.

Two-phase real-time rendering method for realistic water refraction

Background Realistic rendering has been an important g oal of several interactive applications,which requires an efficient virtual simulation of many special effects that are common in the real world.However,refraction is often ignored in these applications.Rendering the refraction effect is extremely complicated and time-consuming.Methods In this study,a simple,efficient,and fast rendering technique of water refraction effects is proposed.This technique comprises a broad and narrow phase.In the broad phase,the water surface is considered flat.The vertices of underwater meshes are transformed based on Snell's Law.In the narrow phase,the effects of waves on the water surface are examined.Every pixel on the water surface mesh is collected by a screen-space method with an extra rendering pass.The broad phase redirects most pixels that need to be recalculated in the narrow phase to the pixels in the rendering buffer.Results We analyzed the performances of three different conventional methods and ours in rendering refraction effects for the same scenes.The proposed method obtains higher frame rate and physical accuracy comparing with other methods.It is used in several game scenes,and realistic water refraction effects can be generated efficiently.Conclusions The two-phase water refraction method produces a tradeoff between efficiency and quality.It is easy to implement in modern game engines,and thus improve the quality of rendering scenes in video games or other real-ti me applications.

Application of real-time 3d echocardiography in mitral valve repair for replacement of chordae tendineae

Objective To investigate the surgical technique and outcomes of replacement of chordae tendineae in mitral valve repair,and evaluate the value of real-time three-di-mensional transesophageal echocardiography in the perioperative period. Methods Thirty-one patients with mitral valve prolapse underwent mitral valve repair using chordae tendineae replacement concomitant with implantation

REAL-TIME SOFTWARE SYSTEM FOR PRODUCTION PROCESS SUPERVISION

The real-time software system for production process supervision is a inte-gral system,including on-line function subsystem for supervision and off-line auxiliarysubsystem for development and diagnosis.This paper introduces a real-time software sys-tem which has been used in a power station for monitoring a large capacity thermal gener-ating unit.The subsystems,environment,performance and development of the system areexplained,and the common problems about real-time software system are described.

Epoch-based Application Collaboration for Sensing Data Analysis

The application collaboration was addressed to provide energy-efficient data services for distributed sensing applications to collaboratively interacting to achieve a desired global objective not detectable by any single cluster. An epoch-based transaction model was proposed by using the concept of sphere of control （SoC）, and a collaborative sensing application can be dynamically formed as a nested architecture composed of time-synchronized applications. By loosening the rigid constraints of ACID to adapt the requirements of sensor networks, the submission, rollback and consistency rules ware educed and a two-phrase submission protocol was designed. Finally, it was illustrated that the model is capable of providing an adaptive formal template for sensing application collaboration. Our performance evaluations show that by applying the two-phrase submission protocol, we can significantly improve the number of reported answers and response time, raise resource utilization, and reduce the energy cansumption and data loss.

Data-based real-time petrochemical gas diffusion simulation approach on virtual reality

Background Petrochemical products possess a high risk of flammability,explosivity,and toxicity,making petrochemical accidents exceedingly destructive.Therefore,disaster analysis,prediction,and real-time simulations have become important means of controlling and reducing accident hazards.Methods This study proposes a complete real-time simulation solution of gas diffusion with coordinate and concentration data,which was mainly aimed at simulating the types of harmful gas leakage and diffusion accidents in the petrochemical industry.The rendering effect was more continuous and accurate through grid homogenization and trilinear interpolation.This study presents a data processing and rendering parallelization process to enhance simulation efficiency.Gas concentration and fragment transparency were combined to synthesize transparent pixels in a scene.To ensure the approximate accuracy of the rendering effect,improve the efficiency of real-time rendering,and meet the requirement of intuitive perception using concentration data,a weighted blended order-independent transparency(OIT)with enhanced alpha weight is presented,which can provide a more intuitive perception of the hierarchical information of concentration data while preserving depth information.This study compares and analyzes three OIT algorithms-depth peeling,weighted blended OIT,and weighted blended OIT with enhanced alpha weight-in terms of rendering image quality,rendering time,required memory,and hierarchical information.Results Using weighted blended OIT with an enhanced alpha weight technique,the rendering time was shortened by 53.2%compared with that of the depth peeling algorithm,and the texture memory required was significantly smaller than that of the depth peeling algorithm.The rendering results of weighted blended OIT with an enhanced alpha weight were approximately accurate compared with those of the depth peeling algorithm as the ground truth,and there was no popping when surfaces passed through one another.Simultaneously,compared with weighted blended OIT,weighted blended OIT with an enhanced alpha weight achieved an intuitive perception of the hierarchical information of concentration data.

A Tiny Example Based Procedural Model for Real-Time Glinty Appearance Rendering

The glinty details from complex microstructures significantly enhance rendering realism.However,the previous methods use high-resolution normal maps to define each micro-geometry,which requires huge memory overhead.This paper observes that many self-similarity materials have independent structural characteristics,which we define as tiny example microstructures.We propose a procedural model to represent microstructures implicitly by performing spatial transformations and spatial distribution on tiny examples.Furthermore,we precompute normal distribution functions(NDFs)by 4D Gaussians for tiny examples and store them in multi-scale NDF maps.Combined with a tiny example based NDF evaluation method,complex glinty surfaces can be rendered simply by texture sampling.The experimental results show that our tiny example based the microstructure rendering method is GPU-friendly,successfully reproducing high-frequency reflection features of different microstructures in real time with low memory and computational overhead.

RenderKernel:High-level programming for real-time rendering systems

Real-time rendering applications leverage heterogeneous computing to optimize performance.However,software development across multiple devices presents challenges,including data layout inconsistencies,synchronization issues,resource management complexities,and architectural disparities.Additionally,the creation of such systems requires verbose and unsafe programming models.Recent developments in domain-specific and unified shading languages aim to mitigate these issues.Yet,current programming models primarily address data layout consistency,neglecting other persistent challenges.In this paper,we introduce RenderKernel,a programming model designed to simplify the development of real-time rendering systems.Recognizing the need for a high-level approach,RenderKernel addresses the specific challenges of real-time rendering,enabling development on heterogeneous systems as if they were homogeneous.This model allows for early detection and prevention of errors due to system heterogeneity at compile-time.Furthermore,RenderKernel enables the use of common programming patterns from homogeneous environments,freeing developers from the complexities of underlying heterogeneous systems.Developers can focus on coding unique application features,thereby enhancing productivity and reducing the cognitive load associated with real-time rendering system development.

Real-time rendering of layered materials with anisotropic normal distributions

This paper proposes a lightweight bidirectional scattering distribution function(BSDF)model for layered materials with anisotropic reflection and refraction properties.In our method,each layer of the materials can be described by a microfacet BSDF using an anisotropic normal distribution function(NDF).Furthermore,the NDFs of layers can be defined on tangent vector fields,which differ from layer to layer.Our method is based on a previous study in which isotropic BSDFs are approximated by projecting them onto base planes.However,the adequateness of this previous work has not been well investigated for anisotropic BSDFs.In this paper,we demonstrate that the projection is also applicable to anisotropic BSDFs and that the BSDFs are approximated by elliptical distributions using covariance matrices.

A Fast Ambient Occlusion Method for Real-Time Plant Rendering

Global illumination effects are crucial for virtual plant rendering. Whereas real-time global illumination rendering of plants is impractical, ambient occlusion is an efficient alternative approximation. A tree model with millions of triangles is common, and the triangles can be considered as randomly distributed. The existing ambient occlusion methods fail to apply on such a type of object. In this paper, we present a new ambient occlusion method dedicated to real time plant rendering with limited user interaction. This method is a three-step ambient occlusion calculation framework which is suitable for a huge number of geometry objects distributed randomly in space. The complexity of the proposed algorithm is O（n）, compared to the conventional methods with complexities of O（n^2）. Furthermore, parameters in this method can be easily adjusted to achieve flexible ambient occlusion effects. With this ambient occlusion calculation method, we can manipulate plant models with millions of organs, as well as geometry objects with large number of randomly distributed components with affordable time, and with perceptual quality comparable to the previous ambient occlusion methods.

Domino Tiling:A New Method of Real-Time Conforming Mesh Construction for Rendering Changeable Height Fields

In this paper we present a novel GPU-oriented method of creating an inherently continuous triangular mesh for tile-based rendering of regular height fields. The method is based on tiling data-independent semi-regular meshes of non-uniform structure, a technique that is quite different from other mesh tiling approaches. A complete, memory efficient set of mesh patterns is created by an off-line procedure and stored into the graphics adapter＇s memory at runtime. At rendering time, for each tile, one of the precomputed mesh patterns is selected for rendering. The selected mesh pattern fits the required level of details of the tile and ensures seamless connection with other adjacent mesh patterns, like in a game of dominoes. The scalability potential of the proposed method is demonstrated through quadtree hierarchical grouping of tiles. The efficiency is verified by experimental results on height fields for terrain representation, where the method achieves high frame rates and sustained triangle throughput on high resolution viewports with sub-pixel error tolerance. Frame rate sensitivity to real-time modifications of the height field is measured, and it is shown that the method is very tolerant and consequently well tailored for applications dealing with rapidly changeable phenomena represented by height fields.

An improved pulse coupled neural networks model for semantic IoT

In recent years,the Internet of Things(IoT)has gradually developed applications such as collecting sensory data and building intelligent services,which has led to an explosion in mobile data traffic.Meanwhile,with the rapid development of artificial intelligence,semantic communication has attracted great attention as a new communication paradigm.However,for IoT devices,however,processing image information efficiently in real time is an essential task for the rapid transmission of semantic information.With the increase of model parameters in deep learning methods,the model inference time in sensor devices continues to increase.In contrast,the Pulse Coupled Neural Network(PCNN)has fewer parameters,making it more suitable for processing real-time scene tasks such as image segmentation,which lays the foundation for real-time,effective,and accurate image transmission.However,the parameters of PCNN are determined by trial and error,which limits its application.To overcome this limitation,an Improved Pulse Coupled Neural Networks(IPCNN)model is proposed in this work.The IPCNN constructs the connection between the static properties of the input image and the dynamic properties of the neurons,and all its parameters are set adaptively,which avoids the inconvenience of manual setting in traditional methods and improves the adaptability of parameters to different types of images.Experimental segmentation results demonstrate the validity and efficiency of the proposed self-adaptive parameter setting method of IPCNN on the gray images and natural images from the Matlab and Berkeley Segmentation Datasets.The IPCNN method achieves a better segmentation result without training,providing a new solution for the real-time transmission of image semantic information.

基于MR混合现实技术的应急仿真应用系统设计

为避免灾难发生时因经验不足导致慌乱而造成更大的损失,使用混合显示技术设计一种应急仿真应用系统。硬件设计中使用蓝牙适配器作为无线网络传输的工具;软件设计中基于混合现实技术重建虚拟现实场景,对图像进行降噪处理,计算各像素点的3维坐标,实时更新粒子位置,对其进行可视化渲染,并获取粒子在混合现实场景渲染下的位置坐标,混合现实视线下的投影距离;对应急逃生路径规划设计一种路径规划算法;在仿真场景的物理模型下,获取应急疏散模拟结果。结果表明:该仿真系统具备实用性,能够完成应急演练时的数据收集与分析。

新一代Web应用框架JSF

本文介绍新一代Web应用框架JavaServer Faces(JSF)。JSF的最终标准于2004年5月颁布,它代表了 Web应用技术的发展趋势。本文分析JSF与现有相关技术的关系,描述JSF的组成、处理流程和开发Web应用程序的过程,归纳JSF的主要优点。同时,针对JSF标准中渲染组件存在的不足,提出JSF与JSP、XML相结合的改进应用方案。

用USM锐化生成铅笔画的新方法

给出了一种根据真实2D图像自动生成相应的非真实感铅笔画的新方法。首先将彩色图像进行Unsharp Mask(USM)锐化处理,再进行色彩缩放运算,得到具有一定半径的图像的边缘细节。然后,为了更好地产生铅笔画的光线效果及其局部走势纹理,采用线积分卷积(LIC)的方法生成类似的效果,并且用适当的图像分割方法来获取有意义的区域进行LIC处理。最后,把前面得到的边缘细节和LIC处理的结果分为两层进行叠底和透明处理就能得到较好的铅笔画效果。试验结果表明:使用本文方法可以产生更接近于手绘铅笔画的效果,并且生成的速度更快。