数控仿真的实时真实感图形显示

数控仿真是 CAD/ CAM集成系统中一个重要的组成部分 .文中提出的方法 ,从动画显示方式、数据结构和消隐算法三个方面进行了改进 ,大大加快了仿真过程中真实感图形显示的速度 .在微机上实现了实时、动态地显示良好的真实感图形 .     

一种改进的扫描线真实感图形显示算法

真实感图形显示是计算机图形学的一个重要组成部分。扫描线算法是一种常用的真实感图形显示算法。文章在扫描线直实感图形显示算法基础之上，对其作了一定的改进。对光照模型增加了衰减变化，并使扫描线算法也适用于曲面，提高了真实感的效果。     

STL格式实体真实感图形显示工具

介绍了一个基于OpenGL的STL格式实体显示工具的设计与实现 ,对用OpenGL实现STL格式实体的真实感图形显示作了重点阐述。     

陶瓷产品造型设计系统的设计与实现

本文介绍了计算机辅助陶瓷产品造型设计系统的设计方法和主要功能。本系统提供了真实感图形的显示,图形逼真,自然。在处理真实感图形中,采用了较合适的花纹映射和光源球面缓冲法处理阴影,使图形生成的真实性和实时性得到较好的统一。     

机器人真实感图形的计算机模拟

本文以一种多闭链式机器人为研究对象，以高档微机为研究工具，以机器人真实感图形显示技术为研究内容，重点探讨了消隐算法及金属体材质感的模拟两大问题。这其中设计了一些独特的算法，对一些关键问题提出了某些新的见解。最后对所开发的该机器人真实感图形显示软件ＲＯＢＲＥＡＬ作了简介。     

应用纹理三角条形以改进真实感图形绘制性能

改进真实感图形绘制性能是计算机图形系统的一个基本问题．文中探讨了一些几何压缩算法对真实感图形绘制性能的影响，这些算法是为了优化使用形体顶点高速缓冲存储器而设计的；研究了这些算法和计算机芯片上纹理高速缓冲存储器的相互作用；提出了一个基于三角条形的简单方法，以通过平衡使用形体顶点和纹理高速缓冲存储器而改进真实感图形绘制性能．最后，通过几个实验来显示文中方法的有效性．     

基于OpenGL的实体真实感图形显示工具的开发

基于对图形开发库OpenGL和STL文件格式的研究,提出了使用STL数据实现实体真实感图形显示的思路,并且给出了利用OpenGL显示STL文件实体的编程步骤,依此开发了三维图形显示工具,该显示工具操作简便,显示效果良好。     

一种光照模型的简化算法

本文给出了在微机上实现真实感图形显示的一种简化算法，提出一种对该算法所带来的误差进行补偿的方法．     

空间曲面真实感图形生成和显示技术

真实感图形是一种计算机图形生成技术,它首先采用数学方法建立所需三维场景的几何描述,然后根据假定的光照条件下计算画面上可见的各景物表面的光亮度,使观察者产生逼真的三维立体视觉效果。本文以空间曲面为例,讨论真实感图形显示技术,即借助于光照、浓淡、明暗技术,生成并显示具有立体感的空间曲面。它具备图像逼真、显示速度快、计算简便等特点,有一定的使用价值。     

STL格式实体真这感图形显示工具

介绍了一个基于ＯｐｅｎＧＬ的ＳＴＬ格式实体显示工具的设计与实现。对用ＯｐｅｎＧＬ实现ＳＴＬ格式实体的真实感图形显示作了重点阐述。     

基于OpenGL的真实感图形绘制技术及应用*

科学计算可视化, 计算机动画和虚拟现实是现代计算机图形学的三个热点, 而这三个热点的核心都是三维真实感图形的绘制。通过VC + + 环境下的编程实践, 系统地总结了基于OpenGL 技术实现真实感图形绘制( 包括反走样、消隐以及光照模型等) 的基本步骤和方法, 并结合具体实例, 介绍了真实感图形绘制技术在地矿工程三维实体构模中的应用。     

基于OpenGL的光照处理技术及实现

光照处理是增强图形真实感最重要的组成部分,包括光照模型的选择和明暗处理.通过研究影响物体表面反射光的相关因素,提出了真实感图形绘制中如何进行模拟光照计算和明暗插值计算的问题.在分析和研究OpenGL图形库下实现光照效果的改善,并系统地阐述了利用OpenGL函数在VC 环境下实现光照图形的基本过程和方法.最后在计算机设备上实例绘制了不同光照处理方法下的对比图形,显示出了真实感光照的效果,同时具有一定的使用指导意义.     

Colour graphics and three-dimensional scene synthesis in image display

Recent advances in computer graphics have allowed the synthesis of realistic scenes consisting of surfaces and their coverings. This can be exploited in image displays, which provide a powerful way of gaining an appreciation of the spatial nature of scientific data. If data variables are represented by the naturally observed properties of realistic scenes, a better appreciation of the data can be attained. This paper shows how sophisticated colour graphics techniques can be incorporated within an image display system to produce realistic three-dimensional scenes. Examples of coloured surfaces representing geoscientific data are shown, and the value, in a graphics context, of the techniques developed for the display of image data is discussed.     

Improved Monte Carlo form factor integration

Form factors are used in radiosity image synthesis to describe the fraction of diffusely reflected light leaving one surface and reaching another. They incorporate fundamental geometric properties of interacting surfaces used for light transfer computation.Many numerical applications such as realistic image synthesis require accurate and simple formula for the form factors from small oriented differential areas (treated as a point with a normal) to different geometrical objects; a disk was used in this paper. The exact analytic solution for the general point-to-disk form factor integral is used to develop more accurate numerical techniques for form factor integration for surfaces commonly in use. The improvements are illustrated with realistic image synthesis.     

用随机分形实现遥感影像的立体造型

随机分形是产生自然景物计算机图像合成的有效方法。将随机分形应用于三维地理信息图像造型中，产生反映地理高程信.色的自然图形，并进一步将图形与遥感图像结合，把传统的平面遥感图像构造成自然三维立休遥感图，产生直观的、有实用价值的立体图形.     

孔壁全景图获取中的图像拼接技术研究

采用钻井后数字摄像获取具有真实感的孔壁全景图以进行地质分析已成为地质勘测的重要方法之一。已有的全景图获取方法存在设备成本高或图像拼接效果不理想等不足。通过控制测井深度,对井下孔壁四周360度的柱面空间投影到像面上得到序列环带图像,并对图像进行展开,运用中值滤波算法对图像进行预处理,通过差值图像匹配原理找出图像的重叠部分进行配准,然后采用贝塞尔曲线的逼近算法对图像进行融合,实现图像间的平滑过渡,最后得到具有真实感的孔壁全景图。实际地质勘测应用表明,该图像拼接技术简单,处理灵活高效,所获取的孔壁全景图具有理想的效果。     

基于粒子和纹理绘制的火焰合成

现有的火焰合成算法多数都是基于粒子系统，其主要缺点是运算量大。本文先用少量粒子勾勒火焰的外轮廓线，再用纹理绘制的方法填充火焰纹理。这样既利用了粒子系统形成轮廓线的真实感，又避免大量的粒子状态运算，并能体现动态火焰纹理的一致性和连续性。     

Visual Perception in Realistic Image Synthesis

Realism is often a primary goal in computer graphics imagery, and we strive to create images that are perceptually indistinguishable from an actual scene. Rendering systems can now closely approximate the physical distribution of light in an environment. However, physical accuracy does not guarantee that the displayed images will have authentic visual appearance. In recent years the emphasis in realistic image synthesis has begun to shift from the simulation of light in an environment to images that look as real as the physical environment they portray. In other words the computer image should be not only physically correct but also perceptually equivalent to the scene it represents. This implies aspects of the Human Visual System (HVS) must be considered if realism is required. Visual perception is employed in many different guises in graphics to achieve authenticity. Certain aspects of the visual system must be considered to identify the perceptual effects that a realistic rendering system must achieve in order to reproduce effectively a similar visual response to a real scene. This paper outlines the manner in which knowledge about visual perception is increasingly appearing in state‐of‐the‐art realistic image synthesis. After a brief overview of the HVS, this paper is organized into four sections, each exploring the use of perception in realistic image synthesis, each with slightly different emphasis and application. First, Tone Mapping Operators, which attempt to map the vast range of computed radiance values to the limited range of display values, are discussed. Then perception based image quality metrics, which aim to compare images on a perceptual rather than physical basis, are presented. These metrics can be used to evaluate, validate and compare imagery. Thirdly, perception driven rendering algorithms are described. These algorithms focus on embedding models of the HVS directly into global illumination computations in order to improve their efficiency. Finally, techniques for comparing computer graphics imagery against the real world scenes they represent are discussed.     

Prediction-based realistic 3D model compression

The benefit of using the geometry image to represent an arbitrary 3D mesh is that the 3D mesh can be re-sampled as a completely regular structure and coded efficiently by common image compression methods. For geometry image-based 3D mesh compression, we need to code the normal-map images while coding geometry images to improve the subjective quality and realistic effects of the reconstructed model. In traditional methods, a geometry image and a normal-map image are coded independently. However a strong correlation exists between these two kinds of images, because both of them are generated from the same 3D mesh and share the same parameterization. In this paper we propose a predictive coding framework, in which the normal-map image is predicted based on the geometric correlation between them. Additionally we utilize the strong geometric correlation among three components of normal-map image to improve the predicting accuracy. The experimental results show the proposed coding framework improves the coding efficiency of normal-map image, meanwhile the realistic effect of a 3D mesh is significantly enhanced.