In order to give this blog (and my own inane ramblings) some focus I will be looking at comparing the Unreal Development Kit vs XNA from someone in the professional industry, but coming at developing for both of these packages as a newb (my professional experience has mostly been in C/C++ and OpenGL and C# with Unity).
Coming from a Unity background the XNA project was fairly intuitive, with only slight modifications (mostly in options and casing). Unity uses lower case for accessors and variables: Vector2.zero, while XNA uses uppercase: Vector2.Zero. I was surprised by the number of options the XNA color value had (like Color.Wheat), otherwise I felt very at home with Visual Studio (Express) and the C# code. Working through some tutorial code I was able to setup the build of the game to run a simple image to the game window. The major difference up to this point is workflow, without an in-game editor developing for XNA will likely require iterative testing of values to tweak certain elements of the game play instead of runtime tweaking (we could of course write functionality that would expose setting some of these values at runtime, but it would have to be done for every case).
Getting into the UDK was a bit more of a learning curve. The editor itself was fairly intuitive (it is similar in some ways to Maya) but as a newb to Unreal there were of course things that I would have to look up the documentation for. It is far less of a jump in and start coding experience with the UDK and much more of an explore the editor and figuring out the directory structure of a project (as well as installing nFringe) and learning the different tools (Unreal FrontEnd versus Unreal Editor). Reading the documentation on a lack of debugger in the UDK is a bit of an issue, which would slightly favor XNA development (with breakpoints etc) versus a lot of debug statements. Also having to learn the syntax of a new language UnrealScript will likely take some getting used to.
From someone coming from a Unity background XNA seems like a much easier initial conversion to begin coding (especially if using C# with Unity). Howerver Unreal does offer some intriguing options that both XNA and Unity do not appear to have. With a bit more practice with the build process and Unreal editor setup I will try and create some small examples to compare the differences in creating different game play elements.
Until next time...
Michael Hubbard
http://michaelhubbard.ca
End of Part 1.