Programming

If you’re developing ARX modules that need to be registered as a COM server, you’re faced with some decisions about how to register them. In the old days before anyone cared about user permissions, registration could be safely accomplished at runtime, even via AutoLISP. Unfortunately runtime COM server registration just doesn’t work reliably any more under limited user accounts, not to mention registry redirection on 64-bit platforms. There is only one reliable way to register COM servers, and that’s doing it at install time under elevated privileges. ...

You may not have noticed, but AutoLISP is still alive and kicking. This is evidenced by the growing community of developers and hobbyist programmers using the latest release of OpenDCL, the free graphical user interface library for AutoLISP applications. If you’re not familiar with OpenDCL, check out the newly released OpenDCL 6.

The MFC version that ships with Visual Studio 2010 is known to cause major explosions in file size when you link statically. To avoid that problem, I use the Visual Studio 2008 build tools for such cases. I recently got quite a surprise when I rebuilt one such MFC application and discovered that the executable had ballooned from 400kb to 2MB in the space of one week despite only very minor changes. ...

When I heard that Bricsys had shipped Bricscad for Linux, I was anxious to get to work on supporting the Linux platform. The first order of business was getting familiar with Linux. For that, I chose Ubuntu 10.10 32-bit running on a VMWare Workstation 7.1 virtual machine hosted on my Windows 7 64-bit workstation. ...

If you’re an ObjectARX programmer, you may still be using Visual Studio 2008 because you’ve been told that you must. It’s true that you need Visual Studio 2008 installed to compile native ObjectARX code, but with Daffodil you can do all your work in the Visual Studio 2010 IDE. ...

One of the stages in simplifying an AutoCAD software problem is to rule out (or in) third party add-ons as the cause. To do that, you’ll need a “plain vanilla” test bed configuration that consists of only the out-of-the-box components with no add-ons loaded. ...

When a customer reports a drawing-specific issue, the next stage in simplifying the problem is to eliminate all drawing content that has no bearing on the problem. Unless the drawing object that causes the problem is obvious and can be immediately ascertained, I use the divide-and-conquer method to zero in on the cause. ...

One of the most important skills in resolving technical problems is not problem solving, but problem definition. Stripping a problem down to its essence often makes the solution obvious. I think this is generally true, but especially true in my experience with software tech support and tracking down software bugs. ...

One of the required tools in a programmer’s toolbox is a tool for comparing files. File comparison utilities have come a long way since the original Unix diff command, but this genre of utilities is still referred to as diff tools. For Windows, I use an open source diff utility called WinMerge. WinMerge includes a shell extension that makes it easy to use from within Windows Explorer. ...

Heap corruption bugs in C++ code can present some difficult debugging challenges. Often the actual corruption goes unnoticed until some apparently random point in the future when the corrupt memory is accessed by unrelated code. In such cases, it’s almost impossible to infer the location of the bug using typical debugging tools. ...

I have more or less completed the task of migrating my internal projects to Visual Studio 2010. Native C++ programmers are pretty low on the totem pole of programming coolness these days, but Microsoft did throw us a few bones. At this point I have to say I’m ambivalent overall with VS 2010, but I really like some of the architectural changes and I’m excited about the future. ...

I was hoping that Microsoft would address the need to target earlier versions of Visual Studio within the Visual Studio 2010 IDE, but since they decided to punt, I tackled the problem myself. I’ve released my solution as an open source project named Daffodil for Visual Studio. ...