BM-Bloggers

The blogs of Black Marble staff

Terrarium

We are pleased to announce that we have successfully produced a Terrarium Academic version for the AI for Games course at the University of Bradford.  The Academic version of Terrarium has a simpler API for developing, as well as Terrain for navigation and Terrain Design Tools, and a bulk game server to allow terrains and bugs to be loaded and run, and a scoring system to turn it into a competitive environment.

'Symbols not loaded' when trying to debug dynamically loaded assemblies in VS.NET

Here is an interesting one for all those who are trying to debug DLL assemblies that you load dynamically in your application.

For example, you have a .Net DLL project in VS.Net 2003 that is set to launch a .Net EXE when you hit F5. In your EXE, using a File Open dialog, you select and then load your .Net DLL and run the code within it. So basically the DLL is not bound or declared to the EXE at compile time, but you still want to be able to set breakpoints in your DLL that get hit when required.

Assembly asm = Assembly.LoadFrom( “mydll.dll” );

This all works fine, you can use the classes in the assembly and debug from within VS.Net. However, the LoadFrom call does place a lock on the file that is only released when the main EXE unloads. Now this may not be an issue for you, but it was for us. You can get round this locking by creating your own Application Domain for loaded DLL assemblies but that is a bit complex. There is a simpler option; that is to load the DLL assembly via a FileStream

FileStream fs = new FileStream(“mydll.dll”,FileMode.Open);
new byte[fs.Length];
fs.Read(b,0,(int)fs.Length);
Assembly asm = Assembly.Load(b);

This places no lock on the file, so the underlying DLL file can be deleted/replaced/reloaded to your hearts content whist the EXE is running.

However there is a problem for debugging, in VS.Net you get the message that the breakpoint in your DLL can never be reached as the symbols are not loaded for the assembly. By the way the way to check what debug symbols (if any) are loaded is to use the Modules window in VS.Net Debug|Windows.

If you use LoadFrom the assembly is loaded and any associated debug symbols (.PDB files) if present, allowing VS.Net to debug into the assembly. This is not the case with the FileStream, you only load what you ask for, if you want a .PDB as well you have to load it manually. To do this you need to use FileStream twice, the first loads the DLL into one byte array, the second loads the .PDB into another byte array. Then use another form of the Load method using both arrays.

Hope this save someone the time it lost us !

Richard

AIFG at the UoB for MS

The Virus Game, for Microsoft and the University of Bradford, was finished and has become an integral part of the AI for Games course at the University. The Virus Game is a tile based board game and has been produced in both a desktop and a bulk game server versions.

Robert

Tech Update for IT Managers & Developers

Black Marble's annual Tech Update for IT managers and Developer took place today. In the developer segment we reprised Chris A's & Don Box's Lap around Longhorn for the local audience.  It was very well received, see you at next years update

Robert

Developing Software for the future Microsoft Platform

Richard and I attended the event Developing Software for the future Microsoft Platform, where we saw Chris Anderson & Don Box's Lap Around Longhorn, it was very entertaining. A series of very interesting demonstrations of WinFS showed how powerful a file system could be. Bill Gates gave the closing session, which provided an interesting insight into the industry.
This was followed by the London Bloggers dinner at Masala Zone with Chris An & Don Box.  However, we had to leave early - to catch our train back to the frozen north - not as a reflection on the food & company, which were both excellent.

Robert

BM-Bloggers is open!

Well this is the first posting to our new BM-Bloggers site. What is BM-Bloggers, it is a blog shared by the all the developers of Black Marble to comment on the development world as they see it. Hope you find it if interest.

Richard