# All entries for Thursday 11 November 2004

## November 11, 2004

Follow-up to Google's aptitude test from Autology: John Dale's blog

An elegant set of answers to the Google aptitude test can be found here. I wish I understood enough Mathematica to have been able to figure out how to use it to solve the problems, especially #17 which intrigued me at the time. I can see what their expression is doing, but I wouldn't have been able to write it.

### Game development: Harder than you think

This article is a really interesting primer on why writing video games is so much harder now than it was ten or fifteen years ago. Some interesting insights into the relatively poor fit of compilers and profilers to games development, and the pain associated with the build-and-test cycle for modern games. But as a games developer from many years ago, the bit that really made me wince was this:-

A programmer just isn't going to be competent in a modern game without a decent grasp of basic linear algebra, as well as geometry in 2D and 3D. We often use 4D representations for basic operations (4D homogeneous coordinates for general linear transformations, and the quaternions to represent rotations) so the ability to reason about higher dimensions is extremely useful. Basic calculus is necessary for all kinds of simulation and rendering tasks. For many rendering tasks, signal-processing mathematics is very important – both linear signal processing as well as the murkier study of spherical harmonics. For any kind of sophisticated simulation, you'll want experience with numerical analysis and differential forms.

Ouch.

Until about five minutes ago, I'd believed that 3G phones didn't really have any compelling use for their extra bandwidth and built-in video cleverness. Downloadable pop videos? Movie trailers? Show your friends the view from your hotel window? Who cares, or wants to pay £2.50 a go?

But I was wrong. If you're deaf, two-way video means you can have a phone conversation with sign language or even lip reading. That is just amazing and it's one of those ideas which as soon as you hear it, seems so obvious as to be barely worth stating – but interestingly it seems that the 3G designers didn't anticipate this use at all.

Luckily, they didn't need to: according to the journal Mobile, 60% of Sweden's hearing-impaired population signed up within three months of a promotion being launched by 3. Awesome.