18 June 2010

Cakeage and Portal

Mmm, cake.

It has recently been birthday season in my family. Angela, Dad and I all have our birthdays within an 8-day period at the start of June. While we were out for dinner at a Sydney restaurant, there was discussion of whether a cakeage fee would apply at the restaurant.

What is cakeage? It’s a per-person fee charged by a restaurant to serve a dessert you have brought to the restaurant, typically a birthday cake. The term, as far as I can tell, is a neologism derived from corkage — a similar fee changed to serve a bottle of wine brought by the customer.

I’m not sure where I sit on the debate over whether cakeage should be charged by restaurants. On the pro side, the restaurant loses the ability to sell you any of their delicious desserts. Usually the cakeage fee is much less than the price of a dessert too. On the anti, there’s not much effort put into serving cakes at many restaurants (we normally take our own candles and matches, for example) so what is the charge actually for? On the balance, I’d probably say that I’m okay with restaurants charging fees like this, as long as they’re clearly advertised. It then becomes a matter of competition between restaurants, where the customers can decide whether they’re willing to pay such fees and vote with their feet.

In the end, I don’t think we were charged cakeage by the restaurant. Even if we were though, it would have likely been a very small component of the final bill.

On the topic of cake, there’s been a bit of fanfare recently about the upcoming release of Portal 2 by Valve Software. The original Portal game is one I’ve only become familiar with recently, since Valve released the game on the Mac. However, it is one of the most engaging and interesting games I’ve played in years so I thought I’d write a little bit about it. (The reference to cake is in the game; you’ll get it when you play it.)

You start the game in what appears to be a scientific research facility. You’re standing inside a large glass box with a bed and a radio. After a few moments, a portal — which looks like a large mirror with a bright blue border — appears on one of the walls inside your glass box. There is also a corresponding portal with an orange border on the wall of the room outside of your glass box. Stepping through the blue portal takes you to where the orange portal is, outside the glass box, where you start playing the game.

The initial stages of the game have you stepping through existing portals, but you quickly acquire a portal gun, which allows you to create blue and orange portals of your own. You can create portals on almost any horizontal or vertical surface in the game. The challenge of the game is to use these portals to navigate your way through a bunch of levels with a variety of hazards.

What is perhaps most interesting about the game is the game physics used when moving through a portal. Wikipedia has an excellent diagram:

Portal physics diagram showing falling into a portal in order to increase horizontal velocity
Portal physics diagram

Momentum is preserved when moving through a portal, so you can use gravity to accelerate you vertically into the blue portal, then position the orange portal such that this is translated into horiztonal velocity and helps you reach an otherwise unreachable location.

Not just momentum is preserved, however. Your angle and direction-of-view relative to the portal are also preserved when you exit the portal. This makes jumping through some portals quite visually exhilirating when you come out “upside down” and gravity quickly swings your view around the right way up.

All in all, it’s a very impressive demo of what Valve’s game engine is capable of. Portal is an incredibly addictive puzzle game with the immersiveness of a first-person shooter. I’d really recommend checking it out, and if you don’t want to pay $20 for a game that’s two years old (I got my copy for free), definitely keep an eye out for Portal 2 coming later this year.