从VCT到DXF数据格式转换_费中强

UG入门教程之-ug和autocadd 的dxf转换一、从Auto CAD到UG因为Auto CAD转出的DXF文件不包含公英制单位信息，所以在Auto CAD产生的DXF文件转入UG 之前，必须进行单位设定。

修改文件dxftoug.def中的单位设定：UNITS = Metric （公制）或者English （英制）。

二、从UG到Auto CAD为了使Auto CAD能识别UG的字体，在UG产生的DXF文件转入Auto CAD之前, 按照以下步骤安装DXF字型文件。

将ugtodxf目录下的字型文件ugtxt.shp和ugmtxt.shp复制到Auto CAD的字库目录下。

编译（compile）字型文件，产生两个文件ugtxt.shx和ugmtxt.shx。

在将UG的drawing转成DXF时，为避免带入实体信息。

应关闭两个转换选择项曲面（Surfaces）和实体（Solids)，或修改文件ugtodxf.def如下：...UGI_CURVE_MASK = Points,Lines,Arcs,Conics,B-Curves,Silhouette Curves,Solid Edges on Drawings,All Solid EdgesUGI_SURF_MASK =UGI_ANNOT_MASK = Dimensions,Notes,Labels,ID Symbols,Tolerances,Centerlines,Crosshatching,Draft Aid by Parts,Stand Alone Symbols,Symbol FontsUGI_STRUCT_MASK = Groups,Views,Drawings,Components,Reference SetsUGI_SOLID_MASK =。

•Download demo project - 167 KbIntroductionWhat is DXF?Drawing Interchange Format (DXF) files enable the interchange of drawings between AutoCAD and other programs. DXF files can be either ASCII or binary formats. Because ASCII DXF files are more common than the binary format, CadLib uses ASCII DXF format.What is CadLib?The CadLib is not a Computer Aided Design (CAD) program. It is a tool for creating DXF files that are used in the CAD programs. It consists of two parts. One of them is a Dynamic Link Library to create the DXF file. The other part is the programming interface. It is a class that integrates the cadio.dll functions. It can be used in Microsoft Visual C++ projects. In addition, the cadio.dll can be used in other Win32 programs.Why use CadLib?In some programs, it is needed to create a drawing output for use in other programs such as AutoCad. For example, in a "Building Detail Sheet Generator Program", the program needs to create a drawing output. And the most standard format for communicating drawing data is DXF.DXF file structureThe DXF format is a tagged data representation of all the information contained in a drawing file. Tagged data means that each data element in the file is preceded by an integer number that is called a group code. A group code's value indicates what type of data element follows. This value also indicates the meaning of a data element for a given object (or record) type. Virtually all user-specified information in a drawing file can be represented in DXF format. (from AutoCad's DXF reference)A DXF file consists of some sections. Each section has some drawing data in itself. The CadLib uses the following sections:1.HEADER2.TABLES3.BLOCKS4.ENTITIESThe main reference for DXF file structure that is used for CadLib is the AutoCad's DXF reference. You can find more information about DXF file structure here.ClassesThe classes are interfaces between CadIO.dll and the main program. "Test" has come with CadLib to demonstrate how to generate a DXF file with CDxfFileWrite and CDrawing classes.CDxfFileWrite classCDxfFileWrite gathers all the commands needed to directly create a DXF file. Usage of CDxfFileWrite is as follows:1.Create the DXF fileCollapse | Copy CodeCDxfFileWrite dxffile;dxffile.Create( "d:\\test.dxf" );2.Begin and end the HEADER section. It's here for compatibility with some CADprograms. Others work without having HEADER section.Collapse | Copy Code// Header Section ------------------------------------------dxffile.BeginSection(SEC_HEADER);dxffile.EndSection();// close HEADER section ------------------------------------3.Begin the TABLES section and put the LAYER, LTYPE, STYLE, DIMSTYLEtable-types as many as you want and then close the sectionCollapse | Copy Code// Tables Section ------------------------------------------dxffile.BeginSection(SEC_TABLES);// LTYPE table type -------------------------dxffile.BeginTableType(TAB_LTYPE);DXFLTYPE ltype;double elem[4];// ContinuousZeroMemory(<ype, sizeof(ltype)); = "Continuous";ltype.DescriptiveText = "Solid line";dxffile.AddLinetype(<ype);// DASHDOT2ZeroMemory(<ype, sizeof(ltype)); = "DASHDOT2";ltype.DescriptiveText = "Dash dot (.5x) _._._._._._._._._._._._._._._.";ltype.ElementsNumber = 4;ltype.TotalPatternLength = 0.5;dimstyle.DIMEXE = 0.1800; // Extension line size after Dimlinedimstyle.DIMEXO = 0.0625; // Offset from origindimstyle.DIMBLK1 = "ClosedFilled";// 1st Arrow headdimstyle.DIMBLK2 = "ClosedFilled";// 2nd Arrow headdimstyle.DIMASZ = 0.1800; // Arrow sizedimstyle.DIMTXSTY = "Style1"; // Text styledimstyle.DIMCLRT = 3; // Text colordimstyle.DIMTXT = 0.1800; // Text heightdimstyle.DIMTAD = 1; // Vertical Text Placementdimstyle.DIMGAP = 0.0900; // Offset from dimension linedxffile.AddDimStyle(&dimstyle);dxffile.EndTableType();// close DIMSTYLE table type ----------------dxffile.EndSection();// close TABLES section ------------------------------------4.Begin ENTITIES section and put entities data (LINE, CIRCLE, SOLID, TEXT,ARC, POINT, DIMLINEAR) and finally close the sectionCollapse | Copy Code// Entities Section ------------------------------------------dxffile.BeginSection(SEC_ENTITIES);// set current layer to Layer2dxffile.SetCurrentLayer("Layer2");// draw a linedxffile.Line(1.2, 3.3, 7.5, 7.7);// draw a circledxffile.Circle(7.8, 4.3, 1.75);// set current layer to Layer4dxffile.SetCurrentLayer("Layer4");// draw a solidREALPOINT points[4];points[0].x = 10.4; points[0].y = 7.2;points[1].x = 13.6; points[1].y = 7.4;points[2].x = 13.1; points[2].y = 4.9;points[3].x = 10.9; points[3].y = 5.9;Solid(4, points);// set current textstyle to Style1dxffile.SetCurrentTextStyle("Style1");// draw textdxffile.Text("Sample Text", 5.9, 6.7, 0.3, 35);// draw a dimension linedxffile.SetCurrentDimStyle("DIM1");dxffile.DimLinear(6.05, 3, 9.55, 3, 9.55, 2, 0, "3.50");dxffile.EndSection();// close ENTITIES section ----------------------------------5.Close the DXF fileCollapse | Copy Codedxffile.Close();CDrawing classCDrawing class has all the commands to create a drawing in memory and save it as a DXF file. Usage of CDrawing is as follows:1.Create the on-memory drawingCollapse | Copy CodeCDrawing drw;drw.Create( );2.Create new LAYER, LTYPE, STYLE, DIMSTYLE table-types as many as youwant.Collapse | Copy Code// Tables Section ------------------------------------------// LTYPE table type -------------------------LTYPE ltype;OBJHANDLE objhandle1;// ContinuousZeroMemory(<ype, sizeof(ltype));strcpy(, "Continuous");strcpy(ltype.DescriptiveText, "Solid line");objhandle1 = drw.AddLinetype(<ype);// DIM1ZeroMemory(&dimstyle, sizeof(dimstyle));strcpy(, "DIM1"); // DimStyle Namedimstyle.dimclrd = 2; // Dimension line & Arrow heads colordimstyle.dimdle = 0.0000; // Dimension line size after Extensionline dimstyle.dimclre = 2; // Extension line colordimstyle.dimexe = 0.1800; // Extension line size after Dimlinedimstyle.dimexo = 0.0625; // Offset from originstrcpy(dimstyle.dimblk1, "ClosedFilled");// 1st Arrow headstrcpy(dimstyle.dimblk2, "ClosedFilled");// 2nd Arrow headdimstyle.dimasz = 0.1800; // Arrow sizedimstyle.dimtxstyObjhandle = objhandle1;// Text styledimstyle.dimclrt = 3; // Text colordimstyle.dimtxt = 0.1800; // Text heightdimstyle.dimtad = 1; // Vertical Text Placementdimstyle.dimgap = 0.0900; // Offset from dimension linedrw.AddDimStyle(&dimstyle);3.Make entities data (LINE, CIRCLE, SOLID, TEXT, ARC, POINT, DIMLINEAR,POLYLINE).Collapse | Copy Code// Entities Section ------------------------------------------// set current layer to Layer2drw.SetLayer("Layer2");// draw a linedrw.Line(1.2, 3.3, 7.5, 7.7);// draw a circledrw.Circle(7.8, 4.3, 1.75);// set current layer to Layer1drw.SetLayer("Layer1");// draw a solidREALPOINT points[4];points[0].x = 10.4; points[0].y = 7.2;points[1].x = 13.6; points[1].y = 7.4;points[2].x = 13.1; points[2].y = 4.9;points[3].x = 10.9; points[3].y = 5.9;drw.Solid(points[0], points[1], points[2], points[3]);// set current textstyle to Style1drw.SetTextStyle("Style1");// draw textdrw.Text("Sample Text", 5.9, 6.7, 0.3, 35);// draw a dimension linedrw.SetDimStyle("DIM1");drw.DimLinear(6.05, 3, 9.55, 3, 9.55, 2, 0, "3.50");4.Save data to a DXF file.Collapse | Copy Codedrw.SaveDXFFile(DxfFileName);5.Destroy CDrawing and free allocated memory.Collapse | Copy Codedrw.Destroy();Loading data from a DXF file1.Create the on-memory drawing.Collapse | Copy CodeCDrawing drw;drw.Create( );e LoadDXFFile member function to load DXF file into memory.Collapse | Copy Codedrw.LoadDXFFile("Sample.dxf");That's all!ConclusionSince I am a Civil Engineer, I decided to write a program to generate a beam or columns detail sheet without the use of AutoCAD. I have written a program that, with a little data about beam or column, will create the detail sheet automatically. Output of this program is a DXF file and it can be shown in AutoCAD or it can be plotted with it. This program can save the time for drawing the detail sheet with AutoCAD. If you are an AutoCAD operator, you will understand the meaning ofwords that are used in this article, or if you are a programmer who wants to write a program to create DXF files, first you need a little knowledge about AutoCAD or the drawing programs such as is mentioned above. This code can be useful for programmers who need to create DXF files from their programs. CadLib is not the best one and also there are many commercial software for creating DXF files but they are not open source. Feel free to change the code. Your comments in regards to this article will cause the improvement of CadLib.History•20 Dec 2002o First release of CadLib•19 Jan 2003o Some bug fixeso Added Dimension-Line support. It's a combination of other entity commands like "Line" and "Solid"o Added BLOCKS section supporto Added Arc, Point and InsertBlock commands for ENTITIES sectiono Text command has been improved•11 May 2003o Added CDrawing class to store drawing data in memory and change the data before saving it as a DXF file.•28 June 2003o Added DXF read capability to CDrawing classo Some bug fixes of CDrawing class when writing data to a DXF file •22 Nov 2003 (CadLib Version 2.00)o Added Drawing View capabilityo Added PolyLine command (by Tran duy Dung)o Improved DXF loading speedo Some bug fixes of drawing memory management functions •24 Aug 2004 (CadLib Version 2.10)o Added ZoomExtents Functiono Improved Viewing functions to show Dashed Lineso Added "ChangeEntity" & "DeleteEntity" commandso Added Dimension view capabilityo Fixed a bug occures when viewing a rotated blocko Improved viewing of textsLicenseThis article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)About the Author用C读取DXF文件Author: eryar@摘要：本文简要介绍了一下DXF文件的组成。

/*-------------------------------------------------* Header.C *读取DXF文件中HEADER段中DXF文件版本号的小程序。 * eryar@ 02-05-08 18:55 *----------------------------------------------------*/ #include <stdio.h> #include <stdlib.h> #include <string.h> #define STRLEN 30 int main(int argc, char *argv[]) { int code; /*存储组码*/ char codevalue[STRLEN]; /*存储组码对应的值*/ FILE *dxf; /*文件指针*/ char filename[STRLEN]; /*文件名*/ char suffix[6] = ".dxf"; /*只输入文件名打开DXF文件，不用输后缀.*/ printf("请输入文件名:"); gets(filename); strcat(filename,suffix); dxf = fopen(filename,"r"); /*打开文件进行读操作*/ if(!dxf) { printf("打开文件出错!/n按任意键退出..."); getch(); exit(0); } else
#define STRLEN 60 #define DATASIZE sizeof(EntityData) /*-----每个实体的结构-----*/ //你可在在此添加其它的实体 //为了提高精度，变量可定义为双精度型 typedef struct tagLine { float x1,y1,z1; float x2,y2,z2; }LINE; typedef struct tagCircle { float x,y,z; float radius; }CIRCLE;//给tagcircle起个别名叫circle /*------------------------*/ typedef union specialData { LINE line; CIRCLE circle; }privateData; /*------实体的数据结构-------*/ typedef struct commonData { char id[STRLEN]; /*实体标识字符串*/ char layer[STRLEN]; /*层名字符串*/ privateData data; /*特有数据块*/ struct commonData *next; /*用于构建链表*/ }EntityData;

段描述等，有点类似于 SuperMap 中的属性表结构； 属性数据就是根据属性数据结构来保存属性数据，导入至 SuperMap 中就是数据集
的属性表内容。 2.2. 导入土地利用数据交换格式（VCT） 2.0
根据《TD/T1016‐2007 土地利用数据库标准》土地利用数据交换格式（VCT） 2.0 文件 包含 8 个层，29 个层要素，其中矢量层要素 25 个。SuperMap 支持这 25 个矢量层要素的导 入，对于栅格数据的 4 个层要素通过 TIFF/BMP 文件单独导入即可。
配置文件，如果配置文件检测合法，则根据配置文件中的内容，对需要导出的面和线数据集 进行拓扑预处理，根据面数据集对应的边界线数据集，在面数据集属性表中创建 Memo 型 的字段 TOPOLINE，记录组成每个面对象的弧段标识码串。下图中，选中的地类图斑，构成 其边界的有四条弧段，则预处理后在该对象的属性表中，TOPOLINE 字段记录的是一串标识 码” 1150427,1152260,1152261,‐1152249”，负值表示弧段的坐标方向为逆时针。如下图所 示：
Set objInParams = Nothing Set objDataPump = Nothing Set objDs = Nothing End Sub
用户只需要设置导入的文件类型、文件路径名即可，方法会自动按照源 VCT 中的要素 类型创建相应的数据集，默认情况下，数据集名称与 VCT 中的要素名称相同。建议一个数 据源下只存放一个 VCT 文件的内容，否则因为要素名称重复，导入另一个 VCT 文件到同一 数据源下，方法会返回失败。下图为示例 代码运行后，导入到当前数据源中 的所有数据集：
VCT 格式数据的导入与导出
1. 关于标准 VCT 格式