Through the Interface

Launching AutoCAD with a specific profile using .NET

This is a follow-up to this previous post, where we used COM to launch the AutoCAD process. Tony Tanzillo rightly pointed out the code in that post could be simplified slightly, so check out his comment for the specifics. Today we're going to look at launching AutoCAD more manually, allowing us to control the working folder and specify command-line parameters. This is to address the specific question of choosing an alternative startup profile for the application, but AutoCAD's command-line parameters allow you to do a great deal more than that. We're going to use the System.Diagnostics namespace to specify... Read more →

Microbenchmarking C# code

Jeremy Tammik, from our DevTech EMEA team, pointed me to this useful and interesting site: http://www.yoda.arachsys.com/csharp/benchmark.html It introduces a very easy way to benchmark functions in your application by simply tagging them with a [Benchmark] attribute (you also need to have included the C# file posted on the above site in your project, of course). Jeremy also highlighted a very pertinent paragraph in the above site: Use local variables where possible. The CLR can do a more optimisations on code which doesn't (for the most part) "escape" from just local variables. For instance, it doesn't need to worry about... Read more →

Getting AutoCAD's current directory from a .NET application

This question came in via a comment from Danny Polkinhorn on this post: After AutoCAD has launched, I often have a need to determine the "Start In" directory specified in the shortcut (Right-click AutoCAD shortcut, Properties, Start in). Is there a way to determine what that directory is? I'm thinking I can use the path of the active drawing (either Drawing1 or the drawing they double-clicked on). Is that a fool-proof way? This is an interesting topic, and raises the questions of what that the "Start In" setting is used for and how it can be modified. The "Start... Read more →

Launching AutoCAD from a .NET application

This topic has been raised a few times, and Adam Nagy, from our DevTech EMEA team, sent a technical response recently with code that I decided to use as the basis for this post. Developers typically want to either integrate functionality into AutoCAD (using its plug-in architecture to add commands, user-interface elements, objects, etc.), or to drive it, automating common tasks. Clearly the line can get blurred between these two areas, but today I’m going to focus on the second category. To help with later explanations, I’d like to introduce two types of application interaction: Out-of-process In this situation... Read more →

Creating an AutoCAD Wipeout using .NET

This topic was suggested via a comment from Dale Bartlett on this post. In AutoCAD 2008 an API was exposed for the Wipeout object. For those of you who aren't familiar with Wipeouts: this handy object was originally developed as part of the AutoCAD Express Tools, and has since been integrated into core AutoCAD. The implementation uses a raster image of the same colour as the drawing canvas to "wipe out" the graphics behind it (assuming it's nearer the front in terms of draw order relative to the entities being masked). This is the main reason the Wipeout class... Read more →

Getting the names of the colors in an AutoCAD color-book using .NET

The last post got me thinking about how to get the names of all the colours that are contained in a particular color-book inside AutoCAD (the last post also contains the explanation for my using both "color" and "colour" in the same sentence, in case that bothers anyone :-). Color-books are stored in .acb files: these files are essentially XML files with the RGB values encoded to prevent people from editing them and polluting the colour definitions on a particular system. So while the RGB information is not directly useful, it is very possible to iterate through these files... Read more →

Using a color-book entry to set the colour of an AutoCAD entity using .NET

Another quick post, as I'm just about to head back home after a long week in Boston. This post comes from a technical solution provided by Sreekar Devatha, from DevTech India. I won't go into detail regarding the following code, but it should be fairly clear what's going on: from a particular colour-name it looks up a colour from a color-book (yes, I know I've used "colour" and "color" in the same sentence, but "color-book" is an AutoCAD term and it's hard for me to drop my u's when I don't have to, even after having lived in the... Read more →

Autodesk Freewheel developer contest

As Scott Sheppard has posted on It's Alive in the Lab, a developer contest for the most innovative Autodesk Freewheel application was launched at AU: http://freewheel.autodesk.com/contest To get a head-start, you might want to check out the source code I've posted here. Good luck! :-) Read more →