Components of ObjectARX applications. Hello everyone, In this article I will introduce the components of ObjectARX™ applications and tools required to develop them ( Fig.1). I know it looks scary. But it gives you amazing customization abilities.
Fig.1 Components of an ObjectARX projec t
As I mentioned in my previous article, ObjectARX™ applications are “. dll” files. Of course, there may be other files like “ .xls”, “.doc”, “.exe”, “.bmp” ect… or other resource files written in other programming languages, “.php”, “.asp” files, database, hardware driver connec con nectio tions, ns, etc etc… … dep depend ending ing on wh what at yo your ur Ob Objec jectA tARX™ RX™ pro projec jectt incl includ udes. es. You sho should uld consider it a project composed of many components and files, rather than a code snippet that can be copy-pasted as part of a macro. This “.dll” file, has “.ARX”, or “.DBX” extension. The main application, which I mentioned above, must be ARX file; however if you create your custom objects, which are derived from AutoCAD objects classes, these classes are stored in a DBX extension file, which is linked to main ARX file. At the starting it becomes scary, why two different files, not one? This idea arises from the separation of UI (user interface) from f rom database operations.
ARX file
In this file you keep the code related to the user interface like toolbars, MFC (Microsoft Founda Fou ndatio tion n Cla Classe sses, s, wh which ich is the sta standa ndard rd dia dialog log bo boxes xes,, but button tons, s, scr scroll oll bar barss etc etc.. tha thatt Microsoft use in Windows applications), AutoCAD commands that your application handle (just like the standard commands you enter from the command line), and other code that organize the general operation of you application. DBX file
In this file, you keep your own “custom classes”. Those who don’t know what “ objectoriented programming programming” is, should skip this part, unless they want to discover a new way
of programming. Those who know about it should also skip because I will try to explain it :) As I mentioned in my previous article, one of the most exciting features of ObjectARX programming is ability to create your own custom objects, which may be related to the concept of “object-oriented programming” in AutoCAD. I will try to explain with an example. As it is mentioned in this article, TABLE command is introduced with AutoCAD 2005®. This table entity is a custom object derived from several line, and text entities combined together to form a TABLE object. I am sure that most of the ObjectARX™ programmers have already created their TABLE objects before AutoCAD 2005®, and used it in their own applications. At least, I have done that. These DBX files or the custom objects inside them are totally reusable, and customizable. Once you create one custom object, you can use it in different applications or you can derive new custom objects from them and adapt them to your new problem. C++ Compiler
Compiler, is a program which compiles the code into and “.exe” or “.dll” file. Thus, we will use a separate program to write our code. Here is a table for C++ compilers for AutoCAD and C++ versions. Sorry for users of versions before 2000, I started with R14
ARXWizard
It is included in ObjectARX™ SDK (Software Development Kit), which can be downloaded from www.objectarx.com for different versions of AutoCAD. This wizard enables us to create our ObjectARX™ projects, files and objects from default templates and add/modify commands (to AutoCAD) that our application will handle. It is nearly impossible to create a working project for a newbie without ARXWizard. When you install it, it adds a toolbar inside VS2002 and adds itself to the other wizards of VS. AutoCAD Libraries
They are also included in SDK. They are inside /inc and /lib folders. Actually, you do not need to deal with these files personally. You just enter these directories into your project settings and compiler. As I mentioned in my previous article, the main idea of ObjectARX™ programming is using AutoCAD’s own source code, but not limited to it, which is composed of these libraries. These libraries include AutoCAD’s own object classes and global functions (like shortcut functions to database related works; angle, distance measurement functions and much more…). MFC (Microsoft Foundation Classes) Libraries
Libraries to use standard Microsoft dialog boxes, buttons etc… Note that, even if you can use your external resources and MFC libraries, AutoCAD libraries also include objects derived from MFC. COM+ (Component Object Model) Connections
For those who used a VBA macro or any other program that enables AutoCAD to communicate with other programs (like EXCEL), has already used COM without noticing it. COM is an intermediate platform which enables different programs (even written in different programming languages) to communicate with each other. Your own Libraries
You can use your own libraries or any other library that is created with C++ or any other programming language. Web Server Connections
For now it’s just my imagination; who needs to include a web server inside an ObjectARX™ application? However, with the development of internet, it enters every field. It is possible to
implement some PHP, ASP, JAVA, AJAX whatever web language you want, through an ObjectARX™ application, will run on a server and work as a part of your project. As you see, I am just trying to enlarge your imagination, because there are no limits for the components that can be added to an ObjectARX™ application. Those I mentioned are only limited to my programming experiences, for more experienced and talented programmers there may be much more… Thanks for reading, and please stay tuned. In my next article, for those who are willing to write their first program, I will explain the installation of basic components ( Fig.1) for an Object ARX application, so that shortly we can write our first “Hello World” program
A brief information about ObjectARX… 1 February 2008, Friday 7:22
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Hello everbody, Today, I will give brief information about ObjectARX, which is one of the innovative steps in history of AutoCAD. It is another way for programming in AutoCAD, just like AutoLISP and VBA. Main difference of it is the programming languages it uses, which is C++ in versions up to AutoCAD 2007® and C++.NET starting with this version. However, as it uses C++ language and it requires knowledge of the programming structure of AutoCAD, DLL (dynamically linked library) etc. it took interest of mainly software developers who develop AutoCAD integrated software products, that are customized in special subjects (i.e. plug-ins, add-ons, modules that are used to aid specific kinds of drawings like reinforced concrete, steel detailing drawings, architectural drawings etc.). Compared to other two customization tools AutoLISP and VBA, ObjectARX is the most complicated one. For example, if you are about to write a code to draw one simple line you can do it in AutoLISP and VBA with only a few lines, besides you can do this inside AutoCAD through the relevant editor. But if you do it with ObjectARX, you will have to prepare a new project in a C++ compiler like Visual Studio, and create up 1-5 (changing from the experience of programmer) code files that needs be compiled together with the AutoCAD libraries the and write up to 100 lines of code. This may sound annoying or just crazy. But the point is, due to the fact that your ObjectARX application is using some part of the original AutoCAD source with ObjectARX, you can control a huge part of run-time environment of AutoCAD. You can manipulate/change the reactions of AutoCAD to specific
actions, you can add new reactions that AutoCAD does when predefined conditions occur, you can add temporary graphics, drawing aids, dynamic objects, user interfaces, database connections, communication with other software/hardware etc.. you can even change whatever you don’t like in AutoCAD’s operation sequence or logic
; shortly whatever you
can program in C++, whatever you can imagine. What you create with ObjectARX is a DLL file, which can be loaded into AutoCAD, similar to loading AutoLISP or VBA applications. It is not different from any other DLL that AutoCAD uses. This is achieved by using some part of the AutoCAD source code. When AutoDESK introduced ObjectARX concept, what they did is simply to open some of their source code (which is indeed a very precious commercial secret) so that third party software developers could use this source code to develop their own applications that works as a part of AutoCAD. This enabled developers to use AutoCAD only for the user interface of their own program or they simply created some specific tools that work as a part of AutoCAD, help those who already use AutoCAD to prepare their drawings. Main idea is that you can apply the “object-oriented programming” with C++. This means that you can use AutoCAD’s basic objects to create your own objects. When you are making a drawing what you are doing is simply to put together the basic drawing objects like lines, texts, points etc. together in a systematic and oriented manner
. For example you are creating a signboard by putting
together a line object as post a text object as something written on it, and a circle, suppose that it is a circular sign board. If you look into any drawing prepared with AutoCAD or any CAD tool, you can such objects prepared in the same manner. What if you could have directly created a signboard object. Up to this point, idea is same as writing a macro, or creating a block, or an attribute. However idea of creating “custom objects” with ObjectARX is far beyond these. While creating a block, you are limited to what AutoDESK has programmed for BLOCK objects, but with ObjectARX you can take the already existing Block object that AutoDESK has programmed inside AutoCAD and add properties or modify existing properties. You can append your own objects, algorithms, combine different objects together and add dynamic properties to the object that is affected by the things that change when you are drawing etc. Here I could only give only a brief information about ObjectARX and what you can do with it. However, due to the wide range of possibilities and control it gives to the programmer, its capacity are limited to the capacity of the ObjectARX programmer
. In my next article, I
will explain the components required for creating an ObjectARX application (C compiler and AutoCAD libraries). Please stay tuned:)
Object ARX software development kit 6 October 2007, Saturday 7:21
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Hello everybody, Today I would like to introduce Object ARX Software Development Kit (SDK). You can download
your
free
copy
of
ARX
SDK
from
www.objectarx.com
or
www.autodesk.com/objectarx. Click on Samples and Documentation and download
executable achieves depending on the version of AutoCAD for which you want to develop ObjectARX applications. Extract them into your hard drive, and you will get the content as shown in Fig. 1.
Fig. 1 Contents of ObjectARX SDK
For different version contents of SDK changes, however general structure and usage is same only some utilities, documentation and samples change depending on the new features introduced in each version of AutoCAD and also in ObjectARX. Of course, the contents of lib and inc folders also change, but you cannot already use them to develop applications for other versions. Now, let’s go over each of each folder in SDK. ARXLABS
In this folder you will find the tutorial help file for developing ObjectARX applications. If you are not familiar with concept of programming with C++ and Visual Studio, it will be hard to follow these tutorials. However, if you follow the instructions one by one it would be a great practice to develop your first ObjectARX application.
DOCS
In this folder you will find the other help files. The main file is arxdoc, which includes all of the other help files. But I suggest you to create a shortcut to your desktop or elsewhere for arxdev, which will be the main reference as it includes definitions of all of AutoCAD’s components that can be used in development of ObjectARX applications. LIB – INC
These two folders are where you can find the library and header files that Visual Studio will be linked to, in order to create ObjectARX applications. SAMPLES
Here you can find the samples for ObjectARX projects. They are also classified for different subjects. Unfortunately they include only the files that make up the project, so they need to be compiled with Visual Studio to create the ObjectARX application. CLASSMAP
In this folder there is an AutoCAD drawing file that shows the classes included in the SDK and their hierarchy. These classes are originally the real classes that are used in AutoCAD. What the SDK does is, it gives the programmer access to these classes by the library files and header files in inc and lib folders so that we can use these classes and their full functionality to develop our applications or create our own classes from them. REDISTRIB
In this folder there are some files that can be included in redistribution packages, so that we can create our own installation files. UTILS
In this folder, you can find utility files. Depending on the AutoCAD version, there are different utility programs in this folder. The most important utility program to be used, especially if you are new to ObjectARX programming, is ARXWizards. When you install ARXWizards, then your Visual Studio will obtain the functionality to create ObjectARX applications from templates and other wizards for implementing members and classes inside Visual Studio in a very easy way.
That’s all for today. Have a nice day.
Programming languages in AutoCAD 20 August 2007, Monday 9:25
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As Taliasoft team, we have been developing applications that work integrated wtih AutoCAD for 16 years. Since the foundation of our company, we created applications for some of the biggest companies in Turkey, like ABB, AEG, Mercedes Benz Türk, Eczacıbaşı Bath Kitchen Ltd., Mood Ltd. We published many publications in various magazines regarding AutoCAD™ applications. And today, we are sharing our knowledge with you through this platform. And from time to time, we are presenting some small applications to you in this web page. We call some of the applications as programs that are AutoLISP , or .NET, or ObjectARX based applications. Even now, I can hear you saying ‘I wonder which one of the programming languages is more suitable for me?‘. In this article, I will try to explain and clarify more details
about
this
subject.
Perhaps, one of the best features of AutoCAD that is the reason why it is selected by many users is that it is a customizable software program. Just like the difference between MAC and PC, even though there are better drawing programs, due to the fact that it is customizable, AutoCAD has been one of the most favourite programs of people who are working in CAD works. Because, nearly all of the user interface of AutoCAD, including its menus, status bar, command line, looking, inside outside…, can be customized. In this article, we will only deal with the programming languages which are used for making parametric drawings. First of all let’s see the summary list:
Table 1 - AutoCAD programming and macro languages Now, let’s briefly go over each of the programming languages: SCRIPT:
It creates text files that has SCR extension. It is used to execute simple AutoCAD (TM) commands one after another. It is generally used for taking repeatedly print outs, slide shows etc. However, even if it is still applicable in today’s versions of AutoCAD, SCR files are replaced by modern commands. DIESEL:
When it is first released, its aim was to give several information regarding coordinates and angles through status bar. On the other hand, it is developed more and it can also be used to create menu macros. It has limited areas of usage, however it can be used for very practical purposes. Let’s have a look at the example together: Command: New value for MODEMACRO, or . for none <”">: $(getvar,clayer)
modemacro
If you change the value of MODEMACRO variable with a DIESEL expression, then you can see the result of this function through the status bar. Layer name that is used in the example is being written on the status line. AutoLISP:
Previously, we used to create LSP files by using any text editor and use these files as AutoLISP programs. However, since AutoCAD™ 2000, we are using Visual LISP program. By using this program, we can one or more LISP files under one project and can be compiled so that they cannot be read. Compiled LISP file includes all of the LISP files and it takes FAS extension. AutoLISP is a programming language which is very easy to learn. It has a very high tolerance with respect to trial and error. Experienced programmers can make very advanced operations by using AutoLISP. Advantages : Easy to learn, it does not require any other additional programming tools
when Visual LISP that exists in AutoCAD is used. It has a very high tolerance with respect to trial and error. Intermediate level complex jobs can be made with LISP in a parametric manner. Disadvantages : User interface is quite had to use. You have to learn the programming
language called DCL. It is not suitable for doing jobs that require speed and performance. It cannot communicate with databases (Except special commands). ADS
(
AutoCAD
Development
System
):
First time AutoCAD™ meets a structural programming language that can be compiled like C, was with ADS. However, lifetime of this language was not so long. Right after it, ObjectARX came and ADS was no longer popular. You need to use compiler programs like Watcom C or Metaware C. However, due to the fact that these compilers did not have IDE, you used to create the C files in an external text editor. Extension of the files were ADS or EXE. Advantages: Compiled code was used to run faster and it was more secure. It was nearly
possible to access all of the features that exist in AutoCAD (TM). Even it was very difficult, it was also possible to connect to databases. Operation system file operations was much faster and easier. Disadvantages : It is very hard to learn C. Compilers that were used was a total headache.
User interface was possible again by using DCL. It was very hard to complete a project unless you create your own library.
Object
ARX
(
AutoCAD
Runtime
Extensions
):
AutoCAD™ met Visual C++ ( Visual Studio 6.0 ( VS6 ) ) in R13 version. It was a revolutionary new feature to create your own AutoCAD™ entities by using C++. In addition, these new entities that you create was able to be edited by using the standard commands of AutoCAD like MOVE, ERASE, COPY as if it is an original AutoCAD entity. Of course it is quite difficult to make this definition. On the other hand, due to the fact that we were using VS6, it was now available to access MFC libraries. This meant that we were now able to use Windows (TM) windows and controls as our user interface, or directly connect to databases, network communication, internet access etc… File extensions can be ARX or DBX. These files are originally DLL files. Advantages : It can create secure files that are very fast during execution. It is very easy
to create database connections and user interfaces. It works in the same level as the internal commands of AutoCAD. Disadvantages: It is very hard to learn. You can make the projects much faster by using
your own libraries DCL
(
Dialog
Control
Language
):
It is possible to create user interfaces while programming with AutoLISP and ADS by this programming language. Main principle can be described as giving a key a label or a property to each of dialog controls. By using this key, you can directly access to the dialog control. It is still in use. File extension is DCL. You can examine the files under AutoCAD (TM) and have an idea about it. .NET
:
By using Visual Studio 2002 or 2005 ( VS2005 ), you can create C#, VB.NET DLL projects. MANAGED EXTENSION DLL which is prepared by AutoCAD as ‘ObjectARX wrapper are assigned to the project as references. Extension of the file that was created is DLL and it is loaded into AutoCAD by using NETLOAD command. Advantages: It is easy to learn. It is quite simple to define a user interface. It is very easy
o connect to databases. You can very easily use the code that you have written in your other projects. Disadvantages: This system is very open to reverse engineering, which means that your
DLL files can easily be interpreted. Microsoft Co. Should work a little bit more about this subject. It works quite slower when compared to Object ARX. You cannot define your own
custom entity. Due to the fact that the created application works in APPLICATION DOMAIN, you cannot remove it from system memory before shutting down AutoCAD. Because of this i t creates a big headache during software development and debugging. VBA
(
Visual
Basic
for
Applications
)
:
This is a system that AutoDESK used to obtain Windows™ compatible certificate. You can create simple VB projects similar to the way that you can create VB macros in EXCEL. Our author Serkan ÖZANT is creating channel drawings programs by suing this system. Advantages: It is very easy to learn. It is very easy to create user interfaces. It is very
easy to connect to databases. Disadvantages: Those who use VBA knows very well that it is very hard to access DLLs and
may create different problems in different computers. In addition, as AutoDESK created this system unwillingly, it is not very helpful for the user. It works relatively slowly. It is expected anytime that it may break something in AutoCAD screen. Technorati Tags: AutoCAD, C++, AutoLISP , Visual LISP, VBA for AutoCAD
Customization Methods in AutoCAD. 12 June 2007, Tuesday 7:55
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General proggraming information There are three different methods that can be used for customization, or in other words programming your own applications in AutoCAD. Below, you can see these three methods as sorted from less complicated to most complicated one. -AutoLISP Macros (Programming language: -VBA Macros (Programming language: Visual -ObjectARX and DBX modules (Programming language: C++)
VisualLISP) Basic)
Let’s examine this there methods together… 1-AutoLISP Macros:
VisualLISP is the oldest of programming languages used in AutoCAD. It might be a little bit old fashioned when compared to today’s complicated programming languages. However, it is extremely useful for custom applications that are developed to use AutoCAD’s own
commands and for purposed that are repeated several times. Compared to other programming methods, it is the easier to learn and use. Another one of its main advantages is that it can be used directly as AutoCAD’s original environment and as if it is AutoCAD’s own commands. 2-VBA Macros:
Visual Basic is specially developed for those who do not require a complicated programming language to develop large, complicated applications; but need less complicated and easy to understand and use programming languages. Its usage and learning procedure is much more easier compared to other programming languages. When compared to LISP it provides wider ranges variations of applications. Similar to LISP, it includes a VISUAL BASIC Editor which is integrated into AutoCAD. This editor is the same editor that is integrated into Ms Office applications like word, excel that is used for creating VBA macros in these applications. Probably, it’s greatest advantage is that it can be programmed through other applications like Word, Excel using the VBA editor of these applications and enable all these programs to communicate with each other in a very easy manner. 3-OBJECT ARX DBX Modules:
When compared to others, this is the one that provides wider range of possibilities but on the contrary, that most complicated one to learn and use. C++ programming language is more complicated compared to LISP and Visual Basic languages that is used in other methods. Other two programming languages are more like scripting languages. They are more efficient to automate basic tasks that repeat themselves. On the other hand, ObjectARX programming uses AutoCAD’s own source code to develop more sophisticated and
specialized applications. Due to the fact that, C++ is an object oriented programming language, you can create your own objects that are specialized for special purposes, either by using AutoCAD’s own objects or entirely new. They are more then a script or a macro. By using ObjectARX, specialized programs that run under AutoCAD, which uses AutoCAD’s user interface as its own graphical interface can be programmed.
But all these make ObjectARX applications more complicated. For example simple tasks like drawing basic entities may require only 2-3 lines of code in AutoLISP and VBA, however same task may be programmed by using 100 lines of code in ObjectARX.
Creating AcDbMaterial object 4: Creating a textured material 17 January 2007, Wednesday 9:21
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Author
Erhan Toker
Profession
Architect M.Sc. Autodesk Authorized Consultant Software Specialist
e-mail
AutoCAD 2007 Now, we have enough information related to materials. So, we can create a general textured material. We can define texture properties by creating another AcGiMaterialMap object in addition to the standard color. Textures are made up of pictures that are already existing in the drawing or saved as a file in hard drive. In our example function, we assume that texture file ( tName ) is stored inside hard drive as a picture file. Here is our function ( Fig. 1):
Fig. 1. To assign properties like Tile, Crop etc… to material definition, you can use AcGiMapper object. However, I suggest tat you should do this operation by the mapping which will be assigned to the material to be texturized. That will be the subject of our next article.
Creating an AcDbMaterial Object - 1 7 December 2006, Thursday 9:42
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Author
Erhan Toker
Profession
Architect M.Sc. Autodesk Authorized Consultant Software Specialist
e-mail
Autocad 2007 programming
In this series of articles, I will explain how to create a AcDbMaterial object in the drawing database. Although this process is very easy, there are some certain points that you should be careful about. I will explain these points and the process to you step by step. Before adding any material to drawing database, you should check if another material with the same name exists in the database. For this reason, we will define hasMaterial(…) funtion first (Fig.1).
Fig.1 Input parameters:
*db : Pointer to drawing database. AcDbDatabase *matName : Material name to query. const ACHAR AcDbObjectId &id : Object ID of the found material. If there is no ‘matName’
material in drawing database, AcDbObjectId::kNull
this
parameter
will
Return true :Material name is exists false :Material is not exists in drawing database. In
AutoCAD
drawings,
( AcDbDictionary
material object).
definitions In
be
in are
order
to
assigned
the
value: database.
drawing
stored reach
inside this
value .
a
dictionary dictionary
AcDbDatabase::getMaterialDictionary(…) function is used. After opening the
dictionary as -open for read-; material is searched inside the dictionary by using AcDbDictionary::getAt(…) function. If the material is found in the dictionary, getAt() function also gets the Object Id of the material. After the process is completed,
dictionary is closed and the return value is returned.
Creating AcDbMaterial Object 2 13 December 2006, Wednesday 9:33
Author
Erhan Toker
Profession
Architect M.Sc.
Print This Post
Autodesk Authorized Consultant Software Specialist e-mail
Autocad 2007 and higher versions
In my previous article, we have checked if the material, we want to create, exists in the drawing database or not. As the second step, we will see how to add a new material to the database. To do this, we will create addMaterial( ... ) function and examine it. ( Fig. 1 )
Fig. 1 Input parameters:
AcDbDatabase *db: Pointer to drawing database. AcDbMaterial *mat: New material definition object. AcDbObjectId &idm: Object ID of the created material. bool overWrite: pass ‘true’ to overwrite existing materials, ‘false’ to avoid overwrite. Return value:
true: Material successfully false: Unable to add material.
added
in
to
dictionary.
First we will check if the material exists in the drawing or not. To do this, we are using the ( hasMaterial() ) function (with mat->name() ) which we have created and explained
in the previous article. If the material that we will add exists in the project, depending on the
overWrite boolean (if it is TRUE or FALSE) variable, either we will directly exit the function or we will overwrite the new material over the existing one. Due to the fact that, by default AcDbDictioanary::setAt() function overwrites the entries that has the same
name, there is no need to delete the old one. After adding the material to the dictionary, we must not forget to close the dictionary and material object. Finally, I would like to remind you that we are not deleting the AcDbMaterial *mat object, we are just closing it.
Creating AcDbMaterial object 3 11 January 2007, Thursday 9:19
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Author
Erhan Toker
Profession
Architect M.Sc. Autodesk Authorized Consultant Software Specialist
e-mail
AutoCAD 2007 After defining hasMaterial() and addMaterial() functions, from now on, we are ready to create a simple texture material. Any AutoCAD material has one or more of diffuse, bump, specular, refraction, opacitiy and reflection properties. At least, a simple material has a diffuse color and in this article I will explain such a material. A simple material only has the property of color diffusion. In ObjectARX library, color object is AcGiMaterialColor. Let’s define a color now (Fig. 1):
Fig. 1.
Together with setMethod() method, we can use kInherit ( last used color from AcGi stream ) or kOverride ( new color definition) options. And, by using setColor() method, we are defining the color that the material is going to make diffused by using RGB components. Besides, we are setting the diffusivity rate of the color by using setFactor() method. Now, let’s create a material and define its diffusion properties ( Fig.2 ).
Fig. 2.
Our material definition is almost finished. However, diffusion property doesn’t spread enough light by itself. We are adding the same color to our material by using setAmbient() function (Fig. 3) as an environment property by using 0.5 factor.
Fig. 3.
Now, our material is ready to be added to the drawing. We are inserting the new material that we have created into drawing data base by using addMaterial() method ( Fig.4 ).
Fig. 4.
I would like to finalize my article by noting that, pointer acdbWDB points to current drawing database, #define
and
it
acdbWDB
workingDatabase(). Related articles
Creating an AcDbMaterial Object - 1 Creating AcDbMaterial Object 2
is
a
macro
definition.
acdbHostApplicationServices()->
