# It's All Geek to Me

Posts about technology, with a focus on web development with Python.

I am the author of Beginning Games Development with Python and PyGame.

I've just uploaded a new version of Game Objects. The 3D maths classes (Vector2, Vector3 and Matrix44) are reasonably stable now. I'd like to invite Python coders to play around with them, and suggest any improvements. My intention was to make something that was very easy to use, but well optimized. Game Objects is public domain. Do what you want with the code - go crazy!

There is no documentation at the moment I'm afraid, but here are a few edited highlights.

I don't often say this, but I miss something from C++ that I can't do in Python. What I miss is unions. I know they can be dangerous and aren't supported consistently across compilers, but damn it, they can occasionally be useful.

I'm working on a 4x4 matrix class (for 3D maths) as part of my Game Objects library. It's something I have done several times in C++, where I create a union of a two dimensional array and four Vector4 classes. That way the matrix is conceptually both a grid of numbers and four vectors, which allows for quite elegant code. For example if I have a CMatrix class that stores the transform for a spaceship and I want to move it forward 2 units, I might use code like this.

Many moons ago I implemented Langton Ants on a ZX Spectrum 48K, and I have been fascinated by it ever since. I thought it would be fun to implement it in PyGame.

Langton ants are simple creatures. They live in a grid of squares that can be one of two colors, and follow these two simple rules.

That is all they do. They don't ponder the meaning of life or current affairs, they just check the color of the square they are on and then turn and move. You would think that something this simple would quickly get in to a cyclical pattern, but it turns out that Langton ants like to make crazy complex patterns and don't repeat themselves. Humor me, while I write a Python script to test it.

First thing we need to do is define a few constants for use in the script, as follows.

sea monkeys. If you are not familiar with sea monkeys - they are a kind of brine shrimp that has been marketed as a kids toy. They come as a little sachet of eggs with a plastic tank. You add water and they hatch within hours. It's the most marvelous, stress-busting executive toy you can buy. I loved my sea monkeys so much, it inspired me to write an artificial life demo (for PC).

I use my laptop for instant messaging and picking up my email while I'm working. It's not quite as good as having dual monitors but it means I can easily work and chat / refer to emails without having to shuffle windows about. Occasionally I need to transfer something from the laptop to my main machine - which can be a pain because I have to minimize windows, find the file, drag it on to a shortcut then find it on the other desktop. What I want is to be able to access the clipboard on the laptop from my main work PC, so that all I would have to do to copy a file from my laptop would be to copy it to the clipboard then press, say Shift+Ctrl+V on the other machine to suck it over the network. And I want it to work with text, urls and anything else that can be copied to the clipboard. And I want it to be free. :-)

A recent post on reddit.com sparked a debate on the following snippet of C code.

The denizens of reddit have been musing over the the output of the code; is it 13 or 14? It can be either depending on the compiler used - or something else entirely - as the result is undefined, which another denizen noted. Sometimes I wonder if the C language was designed purely to provide challenging job interview questions.

Even though I was a C/C++ programmer for a lot longer than I have been a Python programmer, the entire concept of a valid language construct being undefined is offensive to me. Seriously. It's like month old milk; makes me screw my face up and turn away in disgust. In contrast, Python smells like a mixture of freshly cut grass and new car smell.

I hate it so much. I've had willmcgugan.com for many years, and in the early days I was complacent about posting my email address in newsgroups / BBs etc. Consequently I get an impressive amount of spam. I use SpamBayes, which worked great in the beginning, but now training it seems almost as much effort as deleting the spam manually.

Since I can't nuke the spammers from orbit, I've restricted my email address to . Unfortunately this means that you will no longer be able to email me at studmuffin@willmcgugan.com or youreallyrockmyworldiwanttohaveyourbabies@willmcgugan.com (sorry). I have also enabled SPF on my domain. I'm not exactly clear on what that is, but easydns.com claim it will cut down on spam, so I am giving it a go.

Okay, I would be the first to admit that I am getting carried away with these little PyGame experiments. This one renders 3D lissajous figures, which are kind of like a 3D spirograph drawings. It's the first time I have use Game Objects in anything other than a test, and is a good example of simple Vector and Matrix math. Enjoy!

Pygame is a wonderful API for creating games and rich media applications, but the diffulty in distributing PyGame creations may be holding it back from the big time. When you write a game / application / demo, the first thing you want to do is have your friends and family play it, then you want to launch it on the internet, and perhaps even profit from it. To distribute a PyGame app you currently have two choices. You could ask people to install Python and Pygame, plus any other modules you may have used. Which is fine for other Python programmers, but your grandmother may find it tricky - "Are you sure I should click on the snake, dear - what if it has a virus?". The other option is to build a package with Py2exe or similar tool, which works great but requires a little effort to get working and will generate a large bundle of files - and then you are left with the tedious task of making an installer.

The one thing that has always bugged me about sprites in PyGame is that they are so damn finite. Why should I be restricted to an upper bounded number of sprites in my game? Fortunately, I figured out a way of breaking the finite sprite limit, and render an infinite number of sprites to the screen - without any reduction in the frame rate!

Now before you try to convince me this is impossible with such arguments that as "an infinite number of sprites requires an infinite amount of memory", bare in mind that I consider the laws of mathematics to be more rules than actual laws. And rules were meant to be broken, as they say. Not convinced? Download and run this demo, and tell me when you run out of memory. Requires Python and PyGame.