in a drawing, such as lines, circles, and arcs
• Create and manipulate nongraphical objects in a drawing, such as layers, dimension styles, and named views
• Perform mathematical and geometric calculations
• Request input from or display messages to the user at the Command prompt
• Interact with files and directories in the operating system
• Read from and write to external files
• Connect to applications that support ActiveX and COM
• Display dialog boxes and get input from the end user
AutoLISP code can be entered directly at the Command prompt or loaded using a LSP file. Once an AutoLISP program has been loaded, you can execute the custom functions from the Command prompt. Functions executed from the Command prompt can be similar to standard AutoCAD commands, but the programmer determines the prompts that should be displayed. It is also possible to use AutoLISP code with a command macro that is activated from the AutoCAD user interface or a tool on a tool palette.
VBA in AutoCAD
VBA is often overlooked as one of the options available to extend the AutoCAD program. There is no additional software to purchase, but you must download and install a release-specific secondary component to use VBA. You can leverage VBA to perform simple tasks, such as inserting a title block with a specific insertion point, scale, and rotation and placing the block reference on a specific layer. To perform the same tasks manually, end users would have to first set a layer as current, choose the block they want to insert, and specify the properties of the block, which in the case of a title block are almost always the same.
The VBA programming language and AutoCAD Object library can be used to do the following:
• Create and manipulate graphical objects in a drawing, such as lines, circles, and arcs
• Create and manipulate nongraphical objects in a drawing, such as layers, dimension styles, and named views
• Perform mathematical and geometric calculations
• Request input from or display messages to the user at the Command prompt
• Interact with files and directories in the operating system
• Read from and write to external files
• Connect to applications that support ActiveX and COM
• Display user forms and get input from the end user
VBA code statements are entered into the Visual Basic Editor and stored in a DVB file. Once a VBA project has been loaded, you can execute the macros through the Macros dialog box. Unlike standard AutoCAD commands, macros cannot be executed from the Command prompt, but once executed, a macro can prompt users for values at the Command prompt or with a user form. It is possible to execute a macro from a command macro that is activated with a command button displayed in the AutoCAD user interface or as a tool on a tool palette.
What to Expect
This book is organized to help to customize AutoCAD, learn the fundamentals of AutoLISP, and how to use the objects in the AutoCAD Object library with the VBA programming language. Additional resources and files containing the example code found throughout this book can be found on the companion website, www.sybex.com/go/autocadcustomization.
Chapter 1 : Establishing the Foundation for Drawing Standards In this chapter, you'll learn how to establish drawing standards. Drawing standards allow you to enforce consistency across multiple drawings. By enforcing a set of standards, you can easily share your drawings and make them look the same when plotting them.
Chapter 2 : Working with Nongraphical Objects In this chapter, you'll learn how nongraphical objects affect display and output of objects in a drawing. Nongraphical objects such as layers and text styles make it easy to update the look of all the objects that reference them.
Chapter 3 : Building the Real World One Block at a Time In this chapter, you'll learn how to create and manage blocks. Blocks allow you to logically create object groupings that can be used several times in the same drawing. For example, you could create a small assembly of parts and insert it more than once in a drawing. If the assembly changes, you just need to update the block and all instances of that block are changed.
Chapter 4 : Manipulating the Drawing Environment In this chapter, you'll learn how to change the AutoCAD drawing environment. During start up, you can control several of the settings that affect the AutoCAD program. These settings can affect the display of the user interface, behavior of tools in the drawing environment, and where AutoCAD looks for support files.
Chapter 5 : Customizing the AutoCAD User Interface for Windows In this chapter, you'll learn how to customize the elements and display of the AutoCAD user interface on Windows. The Customize User Interface (CUI) Editor allows you to create and manage the tools that are displayed by the AutoCAD user interface.
Chapter 6 : Customizing the AutoCAD User Interface for Mac In this chapter, you'll learn how to customize the elements and display of the AutoCAD user interface on Mac OS. The Customize dialog box allows you to create and manage the tools displayed by the AutoCAD user interface.
Chapter 7 : Creating Tools and Tool Palettes In this chapter, you'll learn how to create and customize tool palettes in AutoCAD on Windows. Tool palettes allow you to create a visual set of tools that can be used to insert blocks, start commands, or even hatch a closed area. Tool palettes are available on Windows only.
Chapter 8 : Automating Repetitive Tasks In this chapter, you will learn how to create scripts and action macros to automate repetitive tasks. Script files and action macros allow you to combine multiple commands into simple logical sequences without needing to know a programming language. Action macros are supported on Windows only.
Chapter 9 : Defining Shapes, Linetypes, and Hatch Patterns In this chapter, you will learn how to create custom shapes, linetypes, and hatch patterns that you can use to control the way line work appears in a drawing. The AutoCAD install provides a limited number of standard shapes, linetypes, and hatch patterns. You can extend the standard definitions by creating your own shapes, linetypes, and hatch patterns for use in your drawings.
Chapter 10 : Using, Loading, and Managing Custom Files In this chapter, you will learn how to use, manage, and migrate custom files. After you have spent the time customizing AutoCAD, all you have left to do is deploy and manage your files.
Chapter 11 : Quick Start for New AutoLISP Programmers In this chapter, you'll get an introduction to the AutoLISP programming language. I begin by showing you how to enter AutoLISP expressions at the Command prompt and execute standard AutoCAD commands. After that, you are eased into some basic programming concepts that allow you to perform conditional tests and repeat expressions. The chapter wraps up with creating and loading an AutoLISP file into the AutoCAD program.