Implementation Technology of the secondary development control of AutoCAD

Recently, the Department needs to add DWG file browsing in the software, which involves converting the DWG to BMP format. At the beginning, it was a mess and I still wanted to use ObjectARX to implement it. After some research, ObjectARX is only a development tool for expanding the functions of AutoCAD and cannot be separated from the AutoCAD environment.

First, we need to clarify a concept: the secondary development of AutoCAD is divided into two categories: 1. Function Extension of AutoCAD Software. For example, to draw some very complex graphics, controls can only be used in the AutoCAD software environment; 2, the reading and writing of DWG files is embedded in software outside the AutoCAD environment.

 

In the AutoCAD environment, the file format is DWG, And the DWG file format is confidential. to parse the DWG file, you must crack the file format. Therefore, open design alliance was born. Open Design alliance organization (ODA) is a famous opendwg company. This organization reversed the DWG file. its official website has such a sentence: our most basic statement of philosophy is this: it is users who own their design data, and it is users who shocould control that data. the general meaning is: our basic point of view is that users have their design data, so they should also be controlled by users.

 

AutoCAD is a CAD software manufacturer with the largest share in the market. Apart from the environment of AutoCAD Software, the read/write function of DWG files is embedded in the software. there are indeed many market demands for this function, however, AutoCAD does not want other software companies to operate DWG files from AutoCAD. The principle is simple: if other companies can operate DWG files, other companies can implement a set of AutoCAD software. AutoCAD confidential DWG file format aims to monopolize the CAD market. As a result, a group of companies specializing in developing the read/write embedded controls for DWG files were born, including autodwg. These companies are basically ODA members, can be found through http://www.opendwg.org/member_list.

Although ODA reverse DWG, It is not disclosed to all people. To obtain reverse results, it must become a member. To become a business member, you must pay an annual fee. The payment method is similar to that in China. The most expensive business member is $25000 for the first year, and then $10000 per year. ODA members can have ODA research results and code. It is very difficult to apply for membership, and there are almost no Chinese enterprises in its membership list. This is why such commercial controls are made abroad.

 

If you are not a member, you can still obtain the ODA development API drxsdk. The embedded control of the read/write function of the DWG file is implemented using this SDK, including the autodwgDwgimage. dll.