3D and 2D/3D holograms model

The estimating problem of 3D holograms orientation selectivity on angular, orthogonal, and azimuthal sensitivity parameters is formulated and solved. Tenfold increase of density 3D, 2D/3D holograms in comparison with 2D holograms at given selectivity for ones is shown in theory and experimentally.     

基于Java3D的不规则形体三维造型及真实感处理

针对Java3D只具有规则形体的三维造型类，无法完成不规则形体的三维造型这一问题，提出用小面片来逼近曲面实现回转体的造型，提出一种变截面曲柄的三维造型方法，同时实现了渲染和真实感处理，是对Java3D功能的必要扩充。     

3D SSD tracking with estimated 3D planes

We present a tracking method where full camera position and orientation is tracked from intensity differences in a video sequence. The camera pose is calculated based on 3D planes, and hence does not depend on point correspondences. The plane based formulation also allows additional constraints to be naturally added, e.g., perpendicularity between walls, floor and ceiling surfaces, co-planarity of wall surfaces etc. A particular feature of our method is that the full 3D pose change is directly computed from temporal image differences without making a commitment to a particular intermediate (e.g., 2D feature) representation. We experimentally compared our method with regular 2D SSD tracking and found it more robust and stable. This is due to 3D consistency being enforced even in the low level registration of image regions. This yields better results than first computing (and hence committing to) 2D image features and then from these compute 3D pose.     

3D user interfaces for general-purpose 3D animation

The paper discusses Virtual Studio software which provides nonprofessional animators with inexpensive and easy-to-use 3D animation systems that have the functionality of complex and costly professional platforms. Virtual Studio is built on Virtuality Builder II, a graphics architecture based on objects and constraints that permits the manipulation and animation of synthetic worlds in three dimensions     

具有三维图形描述功能的页面描述语言(PostScript-3D)

页面描述语言是一种新型的程序设计语言,具有很强的图形描述功能。PostScript-3D是对PostScript语言的三维扩充,它支持三维观察变换、裁剪、3D路径、隐藏线和隐藏面消除、三维线框图和具有浓淡效应的真实感图形。本文对PostScript-3D的实现技术进行讨论,并把它与GKS-3D进行比较。     

利用Sandy引擎实现Flash三维动画

Sandy引擎是目前世界上最优秀的Flash三维引擎之一。利用Sandy引擎,开发人员可以轻松地创建出绚丽的Flash三维动画效果,并实现与用户的交互。该文在详细地介绍了Sandy引擎的基础上,通过具体的实例,深入浅出地介绍了利用Sandy引擎实现Flash三维动画的原理及相关的编程技巧。     

3D Deformable Super-Resolution for Multi-Camera 3D Face Scanning

Low-cost and high-accuracy 3D face measurement is becoming increasingly important in many computer vision applications including face recognition, facial animation, games, orthodontics and aesthetic surgery. In most cases fringe projection based systems are used to overcome the relatively uniform appearance of skin. These systems employ a structured light camera/projector device and require explicit user cooperation and controlled lighting conditions. In this paper, we propose a 3D acquisition solution with a 3D space-time non-rigid super-resolution capability, using three calibrated cameras coupled with a non calibrated projector device, which is particularly suited to 3D face scanning, i.e. rapid, easily movable and robust to ambient lighting variation. The proposed solution is a hybrid stereovision and phase-shifting approach, using two shifted patterns and a texture image, which not only takes advantage of stereovision and structured light, but also overcomes their weaknesses. The super-resolution scheme involves a shape+texture 3D non-rigid registration for 3D artifacts correction in the presence of small non-rigid deformations as facial expressions.     

利用Sandy引擎实现Flash三维动画

Sandy引擎是目前世界上最优秀的Flash三维引擎之一。利用Sandy引擎,开发人员可以轻松地创建出绚丽的Flash三维动画效果,并实现与用户的交互。该文在详细地介绍了Sandy引擎的基础上,通过具体的实例,深入浅出地介绍了利用Sandy引擎实现Flash三维动画的原理及相关的编程技巧。     

Koala 3D: A continuous climbing 3D printer

The size of manufactured parts is naturally bound by the size of their production machines. In this paper, we explore the alternative of making a machine that can continuously navigate along an object being fabricated, producing objects larger than itself. The machine combines a climbing robot and a 3D printer. It uses an infinite fabrication loop which includes printing, reanchoring to a new station, and printing again. We present the design, construction, and characterization of the machine along with experiments on the fabrication of vertical columns. We also demonstrate the freeform fabrication capabilities of the machine by printing a moai statue. The results obtained have a wide range of applications for construction, product fabrication and promisingly broaden the current applications of 3D printing.     

三维U系统矩与三维模型检索

提出3DU系统矩的定义,并将其应用于3D模型检索．作为一种可选定次数的完备正交多项式系统,U系统所定义的矩具有标准正交性、收敛性等优良性质．根据U系统理论实现了U1系统矩的高阶的快速计算,可以定义任意维数的特征空间．实验结果表明,3DU1系统矩优于几何矩和Zernike矩,具有更高的检索效率．     

Web3D技术及新一代标准X3D

阐述了实现Web3D的关键技术及应用前景,VRML97失败的原因,新一代标准X3D的特点和关键技术。     

Java 3D, 3D graphical environments and behaviour

A brief outline of the structure of the Java 3D API as a means of producing graphical environments is provided. We then go on to examine issues in the development of a behaviour rich scene, in particular the issues of scene animation and collisions between scene objects. The animation issue is examined first, where issues of timing and architecture are considered. The Java 3D requirements for, and view of, collision are discussed next from a general perspective, identifying several problems with the implementation. Four simple scenes using animation and collision detection are examined. In each case a number of difficulties have been identified, partly related to the responsiveness of the operating system in the case of animation, but particularly due to the view and implementation of the collision detection system provided. Collisions often involve modifications to the states of all objects involved in the collision and some of the issues this raises in the context of Java 3D's provision are examined and reported on. Finally, we finish with a summary of our findings and conclusions on the suitability of Java 3D for building environments. Copyright © 2002 John Wiley & Sons, Ltd.     

正交样条矩与三维模型检索

提出三维正交样条矩的定义,并将其应用于三维模型检索.作为一种正交多项式函数系,正交样条函数结合球面调和函数所定义的矩具有正交性等优良性质.样条函数的局部性对于突出模型的局部特征有较好的效果.实验结果表明,三维正交样条矩优于三维小波矩,具有更高的检索效率.     

No-Three-in-Line-in-3D

The no-three-in-line problem, introduced by Dudeney in 1917, asks for the maximum number of points in the n × n grid with no three points collinear. Erdos proved that the answer is Θ(n). We consider the analogous problem in three dimensions, and prove that the maximum number of points in the n × n × n grid with no three collinear is Θ(n²). This result is generalised by the notion of a 3D drawing of a graph. Here each vertex is represented by a distinct gridpoint in , such that the line-segment representing each edge does not intersect any vertex, except for its own endpoints. Note that edges may cross. A 3D drawing of a complete graph K_n is nothing more than a set of n gridpoints with no three collinear. A slight generalisation of our first result is that the minimum volume for a 3D drawing of K_n is Θ(n^3/2). This compares favourably with Θ(n³) when edges are not allowed to cross. Generalising the construction for K_n, we prove that every k-colourable graph on n vertices has a 3D drawing with volume, which is optimal for the k-partite Turan graph.     

3D打印机

3D打印机可以将电脑上设计的3D模型打印出来,并可同时构建3D模型。Stratasys将在下半年进行惠普3D打印机的生产。Stratasys目前市场售价最低的3D打印机为uPrint 3D,体积大约为200×150×150mm,售价约15000美元。主要采用FDM(熔融淀积建模)技术。     

3D显示器

今年暑假真是天公不作美,南方阴雨不断,北方却连日暴晒,想外出的朋友估计会"望天止步"了,但不要忘了在家中一样可以娱乐,游戏、电影一样可以让这个暑假五彩斑斓,你只要攒一台高配置的电脑一切都不成问题。     

3D显示器

精装豪华套!坐享家中的全娱乐平台 今年暑假真是天公不作美,南方阴雨不断,北方却连日暴晒,想外出的朋友估计会"望天止步"了,但不要忘了在家中一样可以娱乐,游戏、电影一样可以让这个暑假五彩斑斓,你只要攒一台高配置的电脑一切都不成问题.