Graphic Processing For Complex Text And Table In Engineering Drawing Software

A complete engineering drawing is not simply composed of geometry graphics, and usually it also contains some descriptive texts which convey the information that can’t be expressed by the geometry graphics, those texts are usually complex texts. As a data carrier, table has a clear structure and is easy to be understood, BOM and title bar is the most frequently used tables in engineering drawing software. How to process the complex text and table quickly and efficiently is a great practical value research topics for the engineering drawing software.The purpose of this study is to develop an engineering drawing software which has full functions, reliable performance and good interactive interface. By the in-depth analysis and research of the DWGDirect library, the graphics processing capabilities of the complex text and table have been designed on the JHCAD software platform with the help of Visual C++and object-oriented programming technology.The work which has been done in this paper is in the follow by two aspects. By the in-depth analysis of complex text encoding in AutoCAD, the complex text encoding rules and optimization methods are summed up. Have introduced the glyph description of TrueType font and SHX font, and analyzed the complex text conversion process from character code to text graphics in engineering drawing software. Combined with the multi-text class provided by the DWGDirect library, a complex text object class has been defined in JHCAD with the help of object-oriented programming technology. Have analyzed the complex text processing methods respectively from two aspects of complex text creation and editing, and achieved the complex text in What You See Is What You Get. Based on the theory of Computer Graphics, a method of postioning the member characters by the character graphic area is given. Several special text processing methods are given, and this has improved the text processing capability of JHCAD.By the analysis of several typical table processing methods in the engineering drawing software and the requirement of JHCAD software platform, a table tool has been designed. Based on the basic principle of table drawing and cell drawing, the drawing process of table has been optimized, and this has greatly improved the efficiency of table drawing. Have analyzed the table editing and the solutions are given from three aspects:the adjustment of cell size, the cell merging and splitting, the table data input and editing. After repeated debugging and testing in JHCAD software platform, the procedure written on the research of this paper has received a good application, and has a good pratical value.