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1.
Daniel Thalmann 《Software》1984,14(3):277-290
GRAFANA is an interactive program, which allows the user to produce drawings based on data stored on a disk file. The major advantage and originality of the system is that the user can interactively determine the visual effect of a drawing and immediately see it on the screen. Moreover, any drawing produced by GRAFANA can still be edited by a generalpurpose graphics editor. This system allows the user to obtain precisely the right drawing for any book, paper or report. GRAFANA has been implemented in MIRA-2D, a graphical Pascal extension. It is available for different machines and kinds of graphical devices.  相似文献   

2.
MIRA-3D is a three-dimensional graphical extension of Pascal based on abstract graphical types. The user may define and manipulate complex 3D objects, as well as image transformations. Viewing transformations and attributes are compatible with the ACM GSPC Core System. A large set of graphical primitives are available and the paper discusses the most important ones. Portability has also been an important criterion in implementation.  相似文献   

3.
STRUKEDIT is an interactive graphics system based on top-down methodology. It is especially designed to manipulate very large drawings representing complex entities, such as electronic circuits or an organization chart.STRUKEDIT allows the user to create a drawing according to the principles of step-wise refinement and top-down design. At the highest level, there is a general representation of the object; this object may be divided into several parts, each of which may be drawn in more detail at the lower level. The process of refinement applies again to this level, and so on until all relevant details are included at the lowest level.STRUKEDIT is implemented in the MIRA-2D language, a graphical PASCAL extension based on abstract graphical types. It may be a useful tool in business administration, technical and industrial design, electronic design, and in all areas that involve the representation of complex objects or structures.  相似文献   

4.
Recognition and integration of 2D architectural drawings provide a sound basis for automatically evaluating building designs, simulating safety, estimating construction cost or planning construction sequences. To accomplish these targets, difficulties come from (1) an architectural project is usually composed of a series of related drawings, (2) 3D information of structural objects may be expressed in 2D drawings, annotations, tables, or the composites of above expressions, and (3) a large number of disturbing graphical primitives in architectural drawings complicate the recognition processes. In this paper, we propose new methods to recognize typical structural objects and architectural symbols. Then the recognized results on the same floor and drawings of different floors will be integrated automatically for accurate 3D reconstruction.  相似文献   

5.
张亮  杨青  王振 《微机发展》2012,(2):195-197
CAD系统因其本身具有许多长处,得到了工程设计人员的广泛使用。但它只能处理图形的几何信息,真正具有工程实际意义的图形拓扑信息和参数约束信息均被抛弃了。为了保留更多的图形信息以及让工程设计人员更方便地进行硐室图形的绘制,文中根据采矿CAD图形的特点,把要绘制的硐室图形进行参数化分析,并通过编程调用采矿CAD的接口实现了硐室图形的自动绘制系统。此系统能根据用户输入的参数自动生成硐室的二维和三维图形,这大大减少了设计人员的工作量,提高了设计效率,也有利于计算机辅助设计的进一步发展。  相似文献   

6.
GRAFEDIT is a general-purpose interactive graphical editor. It provides means to create, modify, transform, copy, store and retrieve almost any kind of two-dimensional line diagrams on a CRT terminal. The editor is easy to use even by unexperienced persons. A set of simple and yet powerful commands allows the user to conduct a natural, efficient, and productive dialogue with GRAFEDIT. In response to the commands, the editor displays various guiding messages or prompts for specific actions, and executes the user's instructions. GRAFEDIT is implemented in the MIRA-2D language, a graphical PASCAL extension based on abstract graphical types.The applications for GRAFEDIT are numerous. Among these are business administration, marketing, advertising, graphical design, technical and industrial drawing, electronic design, teaching and audio-visual presentations.  相似文献   

7.
本文介绍的NPU-2D微机交互绘图系统可提供一般工程绘图中常用的直线、圆弧、字符、剖面线、子图等五种基本图素,具有很强的图形编辑功能。用户利用这些基本图素和图形编辑功能,可以很方便地绘制各种工程图。  相似文献   

8.
The goal of this paper is to present a graphical Pascal extension, named MIRA. This extension gives the user the means of defining and using specific graphical types. A complete vector arithmetic has been developed and a new structured type has been introduced: the figure type. Instructions to create and delete figures are discussed and it is shown how the graphical types can be used as other Pascal types. The implementation is carried out by a portable Pascal preprocessor.  相似文献   

9.
S. F.  D. K.  I. N. 《Computer aided design》2000,32(14):851-866
The paper describes the development of a fuzzy knowledge-based prototype system for conceptual design. This real time system is designed to infer user's sketching intentions, to segment sketched input and generate corresponding geometric primitives: straight lines, circles; arcs, ellipses, elliptical arcs, and B-spline curves. Topology information (connectivity, unitary constraints and pairwise constraints) is received dynamically from 2D sketched input and primitives. From the 2D topology information, a more accurate 2D geometry can be built up by applying a 2D geometric constraint solver. Subsequently, 3D geometry can be received feature by feature incrementally. Each feature can be recognised by inference knowledge in terms of matching its 2D primitive configurations and connection relationships. The system accepts not only sketched input, working as an automatic design tool, but also accepts user interactive input of both 2D primitives and special positional 3D primitives. This makes it easy and friendly to use. The system has been tested with a number of sketched inputs of 2D and 3D geometry.  相似文献   

10.
An interactive example-driven approach to graphics recognition in engineering drawings is proposed. The scenario is that the user first interactively provides an example of a graphic object; the system instantly learns its graphical knowledge and uses the acquired knowledge to recognize the same type of graphic objects. The proposed approach represents the graphical knowledge of an object in terms of its structural components and their syntactical relationships. We summarize four types of geometric constraints for knowledge representation, based on which we develop an algorithm for knowledge acquisition. Another algorithm for graphics recognition using the acquired graphical knowledge is also proposed, which is actually a sequential examination of these constraints. In the algorithm, we first guess the next component’s attributes (e.g., size, position and orientation) by reasoning from an earlier found component and the constraint between them, and then search for this hypothetical component in the drawing. If all of the hypothetical components are found, a graphic object of this type is recognized. For improving the system’s recognition accuracy, we develop a user feedback scheme, which can update the graphical knowledge from both positive (missing) and negative (mis-recognized) examples provided by the user for subsequent recognition. Experiments have shown that our proposed approach is both efficient and effective for recognizing various types of graphic objects in engineering drawings. This paper is an extension of our papers published in ICDAR2003 and GREC2003.  相似文献   

11.
基于规则的建筑结构图钢筋用量自动识别系统   总被引:5,自引:0,他引:5  
传统的手工建筑工程量统计方法不仅费时而且容易出错,利用计算机自动完成工程量统计工作则可以很好地解决这一问题.介绍了一个基于规则的建筑结构图自动识别系统(automatic interpretation of structure drawings,简称AISD).该系统以矢量化后的电子图档为基础,通过总结建筑工程图结构特征及绘图规则,自动分析图中的各种图形元素、符号以及其关系,理解各种部件信息,并加以综合,以获取正确的建筑工程钢筋用量.通过对工程图的特征进行详细的研究,总结出一套基于规则的适应不同类型工程图  相似文献   

12.
一个基于图基约束集映射的参数化设计模型   总被引:10,自引:2,他引:10  
文中提出了一个基于图基约束集映射的参数化设计模型 .对图基的概念作了阐述 .提出了一个适合于图基参数化的数据模型和约束集的多元组表示与映射方法 .给出了基于图基实例的约束求解方法和定位算法 ,并对计算方法作了归纳 .在此基础上 ,给出了一个基于图基的一致联动方法 .实践证明 ,基于图基联动的设计方法摆脱了传统的基于点、线、圆、圆弧低层次线素繁琐的交互设计工作 ,提高了 CAD系统的自动化程度 ,使设计人员对产品的设计、维护以及后续分析等过程都具有十分重要的意义 .  相似文献   

13.
对工程图识别与理解研究现状进行深入和系统的综述。工程图识别与理解 的核心在于利用知识表示、图形匹配、符号识别、几何推理、语义提取等技术,自动获取工 程图中各种显式描述(如几何图元、工程符号、工程对象等)及隐式信息(如设计语义等)。 分别对工程图矢量化、工程符号识别及工程对象识别进行了系统分析。在此基础上对工程图 识别性能评测、基准库等进行总结。最后对现有研究的难点及进一步研究方向进行了展望。  相似文献   

14.
To meet the urgent requirement of enterprises for three-dimensional (3D) process models, an approach based on subgraph isomorphism is proposed to solve the matching problem between precursory 3D process model and 2D working procedure drawings. First, the projection drawings of the precursory 3D process model are obtained, then the primitives are extracted and the attributed adjacency graph (AAG) is constructed. Finally, by taking the 2D working procedure drawing as the AAG, and the projection drawing as the...  相似文献   

15.
面向工程CAD的图形库设计   总被引:10,自引:0,他引:10  
传统的图形库技术有两种:一是用户定制固定的图符;二是对图形分类,每一类图形对应一段程序,即图形库与程序库对应。文中在分析这两种图形库技术的基础上,提出了一种通用的图形库结构,该结构支持元件的参数化表示,支持元件的LOD表示,支持设计过程中元件全生命周期内的图形表述,并支持工程设计的项目管理等。  相似文献   

16.
工程图纸识别中,图形对象的表示方法是研究的重点和难点。在矢量化的基础上提出了一种基于拓扑结构的图形对象表示与识别方法,该方法通过矢量化获得各个图形对象的矢量基元,通过建立矢量基元的影响区域确定各矢量基元的拓扑邻接关系图,进而确定图形对象之间的位置关系,为进一步理解识别工程图纸提供了基本的信息。然后介绍了一个应用实例:圆弧角的识别。在实验中,分别用标准数据和真实图纸进行了测试,实验结果显示该算法具有较高的识别精度和识别效率。  相似文献   

17.
In the initial stage of ship design, designers represent geometry, arrangement, and dimension of hull structures, which correspond to product model information, with 2D geometric primitives such as points, lines, arcs, and drawing symbols on 2D drawings. However, designers must translate the product model information defined on the 2D drawings more intelligently in the following design stages. Thus, design semantics could be lost and design processes that follow could be delayed because of errors by mistranslating the information. Here, design semantics mean design intents of the designer, that is, functions and structures which the product must have.In this study, a semantic product model data structure of an initial ship hull structure was proposed, and a semantic product modeling system was developed based on the proposed data structure. The proposed data structure can store semantic product model information such as product design results with the use of 2D wire frame geometrical data, part attributes, and design knowledge. Hence, this information can be used to generate a 3D solid model and production material information for CAPP as needed.The applicability of the proposed data structure and the developed system was verified by applying them to the deadweight 300,000 ton of Very Large Crude oil Carrier’s product modeling procedure. The application results showed that the proposed data structure and the developed system can be efficiently used for overall initial ship design environment.  相似文献   

18.
吴文文  于俊清 《计算机工程与设计》2007,28(17):4257-4259,4262
为了提高科技文档中几何作图的效率,在科技文档字处理软件ScienceWord中实现了一种基于约束的平面几何作图系统.为了构建基于约束的作图系统,对约束的相关理论作了研究,讨论了该作图系统的总体设计框架和构建约束作图系统的一般步骤,介绍了系统中建立元素之间约束的用户界面设计.由于系统充分考虑了图形元素之间的几何关系,用户不必求助于别的软件就能在科技文档中高效地绘制出各种复杂的几何图形.  相似文献   

19.
Describes an approach for multiparadigmatic visual access integration of different interaction paradigms. The user is provided with an adaptive interface augmented by a user model, supporting different visual representations of both data and queries. The visual representations are characterized on the basis of the chosen visual formalisms, namely forms, diagrams and icons. To access different databases, a unified data model called the “graph model” is used as a common underlying formalism to which databases, expressed in the most popular data models, can be mapped. Graph model databases are queried through the adaptive interface. The semantics of the query operations is formally defined in terms of graphical primitives. Such a formal approach permits us to define the concept of an “atomic query”, which is the minimal portion of a query that can be transferred from one interaction paradigm to another and processed by the system. Since certain interaction modalities and visual representations are more suitable for certain user classes, the system can suggest to the user the most appropriate interaction modality as well as the visual representation, according to the user model. Some results on user model construction are presented  相似文献   

20.
A system to query databases using diagrams as a standard user interface is proposed. The system, called Query by Diagram* (QBD*), makes use of a conceptual data model, a query language on this model, and a graphical user interface. The conceptual model is the entity-relationship model. The query language, whose expressive power allows recursive queries, supports visual interaction. The main characteristics of the interface are ease of use and the availability of a rich set of primitives for schema selection and query formulation. The expressive power of QBD* and G+, which are the only languages allowing recursive queries to be expressed graphically are compared  相似文献   

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