1、 PDF外文：http:/ 本科毕业设计（论文） 外 文翻译 年 级： 2004 级 学 号： 20041235 姓 名：任 XXX 专 业：机械设计制造及其自动化 指导老师： 2008 年 06 月外 文翻译 &nbs
2、p; 第 1 页 英文翻译 1 英文 ON COMPUTERISATION AND REPRESENTATIONOF CHARACTERS The commercial need to computerise contours of objects has intensified over recent years as more and more applications endeavour to see
3、k the benefits of visualisation. The primary aim has been to gain a computerised model which closely resembles the original shape and form. The digital form lends itself to be processed by fast processors, and their output to be displayed on graphic de
4、vices such as screen displays and laser printers. The benefits of the digital form are also extended to cater for numerically controlled machines. These are employed to produce outlines through cutting or engraving on paper, metal, plastic or wood. When it comes to digitling
5、the outlines of characters, additional considerationshave to be included in the modelling, design, phase. The aim of these is to capture the uniqueness and the distinct features of a font, which traditionally were realised by a proficient artisans hand and eye. Modern approaches endeavour to gain th
6、e same impact by using a set of pre-defined specifications in the design process. The goal of which is not just to model accurately a desired font, but also to ensure that the displayed version is both legible and aestheticallyacceptable. This paper provides an insight about the design methods used
7、to both model and represent the contours of Latin characters and fonts. It describes the role of the spline as a means of realising the modelling aspect. To this regard, the spline descriptions used by Postscript (BCzier cubic) and TrueType (parabolic) are looked at, and a comparat
8、iveanalysis made. The discussion throughout is levelled at providing a practical understanding of the subject matter. 1.0 Introduction The quest for an accurate and aesthetically acceptable representation of outlines of shape has traditionally been undertaken by experienced artisans. They produced d
9、esired results by using a skilled hand, having an eye for fine detail and an appreciation of the type and form of the shape itself. This process of generating outlines found popularity in the field of typography, where an exact production and reproduction of contours of characters is req
10、uired. The task for the typographer was not just to draw a given outline, but also to 外 文翻译 第 2 页 capture the distinct features of a particular font type. This manual process of modelling characte
11、r outlines becomes rather tedious and time-consuming when one realises that there are thousands of Latin font types available, each comprisingof at least 100 characters. With the arrival of computers, attempts have been made to automate the design process.This has resulted in software programs under
12、 the headings of computer-aided-design (CAD), manufacture (CAM) and geometric-design (CAGD) being developed. The modem typographer uses a particular design package to capture and model a desired font. The process works with some pre-defined specifications,ensuring that the modelled image embodiesthe
13、 desired font features. In view of modem commercial requirements for a fast and accurate means of computerising a given outline, most design systems make use of a mathematical description. This has the attraction, when compared to the manual approach, of providing a modelled
14、image at a faster rate and yielding within, and between, design systems. In addition, the resulting image is in a form which can be transformed (translated, rotated, scaled Ftc) without distortion by using a simple and an appropriated matrix. The simplest mathematical d
15、escription makes use of straight line segments from point to point around the outline. An example of the approach is depicted in Fig 1. Clearly, it can be seen that the resulting model gives a coarse representation of the original. More data points and thus line segments will be required to yield th
16、e desired outcome. Even then, it is not certain whether the resulting representation would be acceptable for aesthetic reasons. Another shortcoming with the line modelling approach is the amount of continuity it gives between joining segments. As it stands, the system can at most provide zero
