Some unusual primitives in the mira graphical extension of PASCAL

The MIRA system is a very general graphics system which may be useful for almost anyone interested in the production of drawings. The system allows the user to create, save, retrieve, modify and delete any kind of drawing: e.g. free-hand drawings, drawings based on geometrical primitives, algorithmic drawings, data plots, texts. Two-dimensional and three-dimensional drawings can be manipulated. The MIRA system is based on two graphical PASCAL extensions MIRA-2D and MIRA-3D. Two interactive graphical editors GRAFEDIT (two dimensions) and HORIZON (three dimensions) allow the non-specialist user to build complex drawings easily.After an overview of the MIRA system, we present the most unusual primitives, which have been developed for use with this system. These primitives can be divided into different classes: graphical types, figure algebra primitives, figure measure functions, figure recognition predicates, image transformations and animation primitives.     

科技文档中基于约束的平面几何作图

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.     

GRAFEDIT: An interactive general-purpose graphics editor

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.     

Low cost computer graphics for micro computers

A graphical output system small enough to fit on a medium range micro computer is described. The system, called Outline, allows the user to produce line drawings in an infinite two dimensional space. It also offers a picture building facility in which the relationship between different sub-pictures is specified by mathematical transformations. A basic set of picture manipulating facilities along with a set of physical drawing attributes for each device is defined. The system is embedded in a high level language for simplicity of use.     

SedLog: A shareware program for drawing graphic logs and log data manipulation

SedLog is a free multi-platform software package for creating graphic sediment logs providing an intuitive graphical user interface. The graphic sediment logs generated by SedLog can be exported as PDF, Scalable Vector Graphics (SVG), or JPEG for use by other drawing applications or for publications. Log data can be imported and exported in Comma Separated Values (CSV) format. The logs can also be printed to any paper size the user wants. Zoom In, Zoom Out, Fit page, Fit Height and Fit Width facilities are also provided to enable the user to customise the workspace size.     

Graceful interaction with graphical constraints

The graphical constraint editor (GRACE), a graphical editor that lets users define graphical, or geometric, constraints, is reviewed. Graphical constraints specify relationships among graphical objects that the system must maintain. Constraints are useful in graphical drawing editors, design activities supported by CAD systems, and graphical user interface construction. GRACE provides mechanisms for explicit and implicit constraint specification using simple and natural means. These include simple direct manipulation methods and a constraints-by-demonstration facility that incorporates both novel heuristics for inferring user-demonstrated relations in an economical fashion and a natural-language explanation tool that helps the user understand the system's inferencing behavior. An overview of GRACE's user interface is presented and details about how users specify graphical relations and query the system to obtain information about them are provided     

基于VB的数学曲线动态绘制

Windows是一个具有图形界面的操作系统,运行在Windows环境下的Visual Basic提供了丰富的图形功能.本文介绍数学曲线的动态绘制方法.     

The Amulet environment: new models for effective user interfacesoftware development

The Amulet user interface development environment makes it easier for programmers to create highly interactive, graphical user interface software for Unix, Windows and the Macintosh. Amulet uses new models for objects, constraints, animation, input, output, commands, and undo. The object system is a prototype instance model in which there is no distinction between classes and instances or between methods and data. The constraint system allows any value of any object to be computed by arbitrary code and supports multiple constraint solvers. Animations can be attached to existing objects with a single line of code. Input from the user is handled by “interactor” objects which support reuse of behavior objects. The output model provides a declarative definition of the graphics and supports automatic refresh. Command objects encapsulate all of the information needed about operations, including support for various ways to undo them. A key feature of the Amulet design is that all graphical objects and behaviors of those objects are explicitly represented at run time, so the system can provide a number of high level built-in functions, including automatic display and editing of objects, and external analysis and control of interfaces. Amulet integrates these capabilities in a flexible and effective manner     

A Top Down Method for Interactive Drawing

Traditional interactive drawing programs adopt a bottom-up approach, allowing the user to construct a picture by the use of discrete tools, for example, lines, circles, rectangles, and so on. This paper presents a different approach, which allows users to construct graphical objects by stretching and cutting existing objects. The representation is simply implemented, based on a ring of cubic Bezier curves, and use of the de Casteljau algorithm.     

XAnimate: an educational tool for robot graphical simulation

XAnimate has been developed at The Ohio State University to provide portable graphical simulation capabilities at no cost. XAnimate's graphical user interface, C library of functions, and a set of predefined objects enable users to easily display animated wireframe images or solid color objects for robotics systems of any topological structure. The use of X Windows and C allows the package to be ported to almost any Unix system     

CompSurf: an environment for exploring surface reconstruction methods on a grid

CompSurf is a novel visualization system that enables researchers in the area of geographic information systems to compare multiple surface reconstruction techniques simultaneously. The system displays two digital elevation models and grid-based contours from which the surfaces are derived. The researcher can view the surfaces from any angle and examine statistics for each. The system's object oriented design allows the researcher to add new interpolation or approximation methods easily; a dynamically linked library obviates the need for system recompilation. A graphical user interface allows easy manipulation or computation of surfaces, and automatically incorporates new reconstruction methods added to the system.     

Graphically Defining New Building Blocks in ThingLab

ThingLab is a constraint-oriented, interactive graphical system for building simulations. A typical problem in ThingLab (and in systems like it) is that, to define an object with a new kind of constraint, the user must leave the graphical domain and write code in the underlying implementation language. This makes it difficult for less experienced users to add new kinds of constraints or to modify existing ones. As a step toward solving this problem, the system described here allows the graphical definition of objects that include new kinds of constraints. This is supported by an interface in which a user can open two views on an object being defined, a use view and a construction view. The use view shows the object's normal appearance; the construction view contains additional objects and constraints, which serve to graphically specify the new constraints on the defined object.     

NPU-2D微机交互绘图系统

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。     

Design and development of EASEL: a portable UIMS tool

EASEL is a layout and graphical editor which allows users to describe graphically the appearance of objects which are to be manipulated at run-time by the UIMS and the application. Objects may have multiple representations and users may manipulate and change these representations using the EASEL system. Different graphical user interfaces can be easily generated and evaluated at run-time with no need for recompilation. This paper describes the design and development of the EASEL system.     

Object-oriented specification of user interfaces

This paper presents an object-oriented approach for the specification of graphical user interfaces. Specification starts with the analysis of the end user's operations. The user interface is then designed on the basis of this analysis. Operation analysis is followed by structure and component specification which presents the dialogue structure of the application and the contents of each dialogue. Visualization produces the final screen layouts, and task specification documents the usage of the user interface for the purpose of creating user's guides. The method presented in this paper makes it easier for a designer to take the end user's needs into account. Still, it does not automatically guarantee good quality user interfaces. The top-down nature of the method allows the designer to concentrate on the most important aspects of the user interface and split the design procedure into manageable pieces. Also, the visibility of the process allows the designer to communicate with other people while specifying the user interface. This paper connects the method with the object-oriented specification of entire applications. It briefly explains the connections with object-oriented analysis and design, and demonstrates how to implement the specified user interface in an object oriented fashion. The approach presented in this paper is being applied in the development of a large network management system with about two million lines of C++ code running in the XII environment. Still, the method does not require the specification being implemented with any specific windowing system. The only requirement is that the user interface is based on graphical elements, such as dialogues, push-buttons and text fields.     

基于GTK+的嵌入式图形系统性能优化研究

现有GTK+on DirectFB图形系统对硬件加速的优化不够,在国产嵌入式平台上开发的图形系统性能偏低。为此,提出图形系统的性能优化方法。优化图形构件的存储分配策略,用于减少CPU访问显存和内存速度的差异。采用绘图指令的底层扩展方法,提高椭圆填充、多边形填充等扩展绘图指令的执行效率。测试数据表明,在开启硬件加速情况下,构件存储分配优化策略可使CPU绘图指令的执行速度提高数倍至数十倍,与传统应用层扩展方法相比,扩展绘图指令的底层扩展方法硬件加速比高出5倍左右。     

A Dynamic Gesture Language and Graphical Feedback for Interaction in a 3D User Interface

In user interfaces of modern systems, users get the impression of directly interacting with application objects. In 3D based user interfaces, novel input devices, like hand and force input devices, are being introduced. They aim at providing natural ways of interaction. The use of a hand input device allows the recognition of static poses and dynamic gestures performed by a user's hand. This paper describes the use of a hand input device for interacting with a 3D graphical application. A dynamic gesture language, which allows users to teach some hand gestures, is presented. Furthermore, a user interface integrating the recognition of these gestures and providing feedback for them, is introduced. Particular attention has been spent on implementing a tool for easy specification of dynamic gestures, and on strategies for providing graphical feedback to users' interactions. To demonstrate that the introduced 3D user interface features, and the way the system presents graphical feedback, are not restricted to a hand input device, a force input device has also been integrated into the user interface.     

Techniques for Edge Stratification of Complex Graph Drawings

We propose an approach that allows a user (e.g., an analyst) to explore a layout produced by any graph drawing algorithm, in order to reduce the visual complexity and clarify its presentation. Our approach is based on stratifying the drawing into layers with desired properties; to this aim, heuristics are presented. The produced layers can be explored and combined by the user to gradually acquire details. We present a user study to test the effectiveness of our approach. Furthermore, we performed an experimental analysis on popular force-directed graph drawing algorithms, in order to evaluate what is the algorithm that produces the smallest number of layers and if there is any correlation between the number of crossings and the number of layers of a graph layout. The proposed approach is useful to explore graph layouts, as confirmed by the presented user study. Furthermore, interesting considerations arise from the experimental evaluation, in particular, our results suggest that the number of layers of a graph layout may represent a reliable measure of its visual complexity. The algorithms presented in this paper can be effectively applied to graph layouts with a few hundreds of edges and vertices. For larger drawings that contain lots of crossings, the time complexity of our algorithms grows quadratically in the number of edges and more efficient techniques need to be devised. The proposed approach takes as input a layout produced by any graph drawing algorithm, therefore it can be applied in a variety of application domains. Several research directions can be explored to extend our framework and to devise new visualization paradigms to effectively present stratified drawings.     

Computerized control system and interface for flexible micromanipulator control

Micro- and nanomanipulators are essential for a broad range of applications requiring precise micro- and nanoscopic spatial control such as those in micromanufacturing and single cell analysis. These manipulators are often manually controlled using an attached joystick and can be difficult for operators to use efficiently. This paper describes a system developed in MATLAB to control a well-known, commercial micromanipulator in a user friendly and versatile manner through a graphical user interface (GUI). The control system and interface allows several types of flexible movement controls in three-axis, Cartesian space, including single movements, multiple queued movements, and mouse-following continuous movements. The system uses image processing for closed loop feedback to ensure precise and accurate control over the movement of the manipulator’s end effector. The system can be used on any electronic device capable of running the free MATLAB Runtime Environment (MRE) and the system is extensible to simultaneously control other instruments capable of serial communication.     

Prtds — a pascal run-time diagnostics system

A run-time diagnostics system has been described that allows the user to interrogate a program fully in source language terms. In particular, dynamically created data structures are catered for. The diagnostics system allows all objects including those created dynamically to be interrogated and can display a graphical representation of linked data structures. This paper describes the implementation of such a system with the language Pascal on a GEC 4080.