共查询到20条相似文献,搜索用时 551 毫秒
1.
中国当代图学学科的建制发轫于图学教育。著名图学家赵学田教授,以毕生的精
力献身图学教育、普及图学知识,教学中将机械制图最基本的投影几何知识点编成歌诀、以口
诀讲授,积极倡导图学电化教学;并筹办湖北省制图学会暨全国制图学术交流会、成立中国工
程图学学会、推动中国图学史--即学科历史的研究,为中国当代图学学科的建制化过程作出
了贡献,他是中国图学学科建设的奠基人。 相似文献
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王钲旋 《计算机辅助设计与图形学学报》2001,13(12):1148-1149
1 引 言在《关于透视变换的研究》(以下简称为文献[1 ])一文中提出 :“二点透视是经旋转平移方法得到的”,这种提法不符合二点透视投影等基本概念 ,但文中论证较难令人信服 .问题的关键在于对一些基本概念应该如何理解 .以下将说明对于一些概念我们与文献 [1 ]的不同理解 ,与作者及同行商榷 .2 透视投影和透视变换文献 [1 ]中的第 1句就提到 :“计算机图形学中的透视变换……”,严格地说 ,“透视投影”和“透视变换”不相同 .计算机图形学中关心的是透视投影 ,因为它要解决在二维表面上绘制三维形体的问题 .透视投影是已知投影中心和投… 相似文献
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以前主要以二维气象云图作为各级气象部门服务研究与预测的依据,而新兴的三维气象模拟具有形象、动态等突出优点,三维气象可视化技术已成为国际研究的热点.在基于OSG五维气象可视化软件中主要功能模块分为:风力场动态模拟、填色图、等值线、体绘制.为满足实时性的需求,在风力场、填色图的绘制中,采用在场景图直接建立几何节点,在几何节点增加回调自定义画法的方法,对等值线的绘制采用缓存、抽点、内插的方法,对体的绘制采用在场景图直接建立XYZ三方向切片集几何节点,通过"最正对"来控制某方向切片集出现的方法.同时给出了软件的功能及实验结果. 相似文献
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杨忠根 《中国图象图形学报》1998,3(7):538-543
基于旋转体的三维模型研究了透视投影下的旋转体剖节线和侧轮廓线的几何性质及其计算方法,并在此基础上成功地开发了一个从单幅透视投影灰度图象识别和复原旋转体的三维视觉信息的新技术。大量的实验表明该技术是精确、有效和可靠的。 相似文献
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分析了轴测图的投影原理、实际绘法以及在实际中用轴测图绘制零部件拆装图的方法。在AUTOCAD中仿照其二维绘图功能中绘制正等轴测图的功能模式,编写了一段LISP程序,为方便绘制其它形式的轴测图,提供了一个实用工具。 相似文献
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基于几何与图像的混合建模与绘制是解决复杂几何模型快速绘制的一个有效途径。提出一种复杂几何模型的混合绘制方法,首先给出基于风何投影的Warp变换公式,然后对几何模型进行预绘制,得到具有深度的图像;依据图像分辩率的对该图像进行几何重构,得到具有几何拓真诚关系的图像模型,并对该模型进行进一步修正;最后解决了模型的冗余检测问题。实验结果表明,该方法可以在保证较高逼真度的前提下实现复杂模型的快速绘制。 相似文献
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基于MATLAB的Koch分形图生成算法研究 总被引:1,自引:1,他引:0
分形理论作为一门新兴的数学分支,对传统几何学的一个延伸,具有十分广泛的应用前景。用计算机绘制分形图的算法理论及程序设计已成为一个独立的研究方向,使用计算机绘制分形图形提供了一种高效的分形图生成方法,有力的促进了分形科学的发展,同时分形图案应用于实际带来了巨大的经济利益,并促进了其他学科的进一步发展。在详细介绍了绘制Koch分形图的计算机算法的基础上给出了使用MATLAB语言编写的计算机算法的实现过程。对其他分形图的绘制也有一定的参考作用。 相似文献
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Demonstrating the approach to protract the figure of three-dimensional graphs with geometrical forms in two-dimensional planes, graphics is a basic technical discipline of examining protracting engineering drawings using the method of projection and addressing issues on space geometry as well as its theory and approach. Graphics is also a kind of semiotic system of writing. China boasts of rich tradition of graphics with amazing architectural drawings in Pre-Qin period, booming theories of graphics in Wei and Jin Dynasties, refined protracted drawings in Song and Yuan Dynasties, and graphics being regarded as important instruments in Ming and Qing Dynasties when thorough apprehension were pursued in order to seek the practice of administration. It not only forms the basis for modern and contemporary graphics in China, but also shapes the future development of graphics. 相似文献
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工程设计中多图联动建模技术提供用户友好的工程设计空间,建立了工程原理图和多个工程布置图之间的信息关联。采用3D数据存储——2D图形可视转换技术,得到图形变换矩阵。把设备的各个视图的图块预存入图形库中,绘图时,设置相应的绘图图层,只要在布置图的一个视图中插入设备图,系统会在其他视图中自动插入相应的投影图形,并且当修改或者删除一个视图中的图形时,其他视图对应的图形也会自动完成相应的操作,实现了多个工程视图的联动。 相似文献
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《墨子》是我国古代最早论述图学知识、图学思想的科技史著作。《墨子》一书
中的论述与记载表明:图形、图样与文字、数字一样,在人类的社会进步和科技发展过程中起
着不可替代的作用。对《墨子》的研究,特别是对其图学基本概念与基本理论的探讨及其历史
地位;仍是一个有待深入和系统阐明的课题。本文通过考察《墨子》对有关图学理论研究的尝
试,探讨中国古代科学技术中的图学实践与图学知识的成果,以及这些图学成果所体现的中国
图学传统与科学探索精神。 相似文献
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Laser projection, such as that used in laser light shows, usually uses computer-drawn graphics. However, some restrictions are imposed by laser-scanned displays on these vector-based drawings. This paper presents a general vector-oriented drawing method to display computer vector graphics on different laser-scanned displays with optimization. The method considers how to solve the three fundamental problems inherent in laser projection: achieving constant beam intensity, blanking timing and corner overshooting. A velocity parameter has been used to achieve constant beam velocity for all strokes. Blanking timing which is related to turning on/off the laser beam has been examined and a simple test pattern is presented to estimate the total delay that exists in the laser-scanned display and compensate for it. In addition, an optimized approach to avoid corner overshooting and ringing is proposed: the dwelling time of the laser beam at a corner is set according to the corner angle. Moreover, a comparison between the proposed method and the point-oriented method in terms of speed has been presented. It is demonstrated that the vector-oriented approach outperforms the point-oriented approach. Thus, this paper describes the fundamental problems related to laser graphics that must be well considered when drawing with any laser-scanned display. 相似文献
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Liang-Hua Chen Jiing-Yuh Wang Hong-Yuan Liao Kuo-Chin Fan 《Image and vision computing》1996,14(10):753-761
Separating characters from graphics is an important step towards automatic document understanding. In this paper, we propose a robust algorithm to separate Chinese characters from graphics. Our approach is based on clustering the feature points in an image. Two remedy procedures are also proposed to solve the problems caused by the thinning process. This will obtain a better localization of feature points and improve the performance of the separation process. Using our algorithm, all Chinese characters can be separated from graphics without regard to the font style or orientation of the character. Furthermore, our algorithm can also handle the serious case where characters touch/cross lines. The proposed algorithm has been successfully tested on several kinds of line drawings, such as land register maps and form documents. 相似文献
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组合体投影分析与构型设计是工程图学课程的基本内容之一,是工程师阅读工程
图样和设计零件几何结构细节的基础。为此,通过一系列示例,提出一种基于等腰三角形、等
腰直角三角形、正方形、圆形及方圆组合组成的全等几何图形作为两面投影,以棱柱、棱锥、
圆柱、圆锥、圆球和圆环等基本单元通过线面/形体分析法进行空间发散构思进而派生多种组合
体及其第三面投影,并用CATIA 软件建立对应的三维几何模型。该方法为拓展空间思维能力和
几何构型设计提供了基本素材,增强了投影分析过程的逻辑性和趣味性。 相似文献
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《Journal of Systems Architecture》2000,46(3):275-296
In this paper a process visualization development system and its associated development methodology are presented. This methodology is optimized to systems that have complex structure and are built of large number of components belonging to relatively small number of types. In order to handle the complexity, the input requirements of the method are as close to the “native language” of the application as possible. The elements of the native language are assumed to include engineering drawings and manuals describing the operation of the component types the system is built of. Graphics techniques are used to supply the engineering drawings into the development system while not only the required visual appearance is described but the structure of the underlying system is also defined. The elements of engineering drawings are dynamized to animate the graphics presentation, to reflect the current state of the monitored system. Component manuals are transformed to interface and state definitions from which a code generator generates a C++ class for each component type. This C++ class must be tuned to reflect the operation of a single component type. From these definitions the development system automatically builds up the complete visualization program, providing easy and fast application development. 相似文献
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吴恩华 《中国图象图形学报》1996,1(3):232-237
对计算机图形学及至图形工程作了简要的介绍,并论述了图形与图象工程的关系。基于目前我国图形工程的研究以及有关文献的分布情况,在1995年出版的一些重要期刊上选取了近百篇有关图形工程的论文并根据其内容进行了分类统计。旨在使读者对图形工程的发展状况有一个总体了解,并对从事这一领域工作的读者查阅文献提供方便。 相似文献