Monday, February 22, 2010

Collision detection and physics in XNA

It’s like a Lego owner admitting that they prefer Duplo, but I’m fond of C# and XNA for game making. If you don’t need every ounce of performance, then C# can greatly cut down your coding time.

One of the things which is lacking from XNA is a collision/physics system. There are some ‘wrapped’ unmanaged libraries, but if you want to leave the door open to running your game on 360 then you need a 100% unmanaged solution.

I just came across JibLibX (via here), which is a native port of JibLib (i.e. someone took the C++ code and rewrote it in C#). I’ve only run the sample so far, but it looks good.

Here’s a video of someone having fun with JibLibX.

Friday, February 19, 2010

Why penny stock tips are a scam

The following is conjecture on my part, but it seems sound to me.

Here’s my easy, step by step guide to becoming seriously rich with penny stocks.

  • Create a simple website telling people to sign up for your penny stock tips.
  • Advertise the site anywhere where uneducated potential investors might be. (The greedier and stupider the better.)
  • Choose a penny stock which seems like a good investment. Ideally you’ll do some good research and find a sound deal, but you can just pick one at random if you like.
  • Gradually buy up a bunch of stock in that company at its current low price.
  • Create 'sell orders’ with your broker to sell the stock if it goes up by a certain percentage, let’s say 25% up from where you just bought it.
  • Write a convincing letter about why you think this stock is about to “EXPLODE!”. Say you’ve got some magic system which is almost always right.
  • Mail all the people on your mailing list to tell them to ‘buy it right away’.


  • Your mail goes out, and some percentage of your readers buy the stock.
  • As penny stocks have low volume, there are few people currently attempting to sell the stock. This means that the people with sell orders (you) can pretty much ‘name their price’. This is different with regular stocks where the volume is so high that there are lots of people trying to sell the stock around the current price.
  • They buy their stock from you, at the price you decided that you wanted.
  • The stock price (i.e. what people are paying for the stock) shoots up, just as you predicted! (You’re a genius!)
  • The people buying the stock have a short period to resell it to others caught in the frenzy.
  • Then things calm down. There are no more frantic buyers to push the price up. Some people sell at a loss to get back out, and the price of the stock starts falling back down to the pre-boom level. Unfortunately, your helpers are stuck with stock that’s hard to sell and people aren’t buying – but that’s not your problem.
  • You get to cite the huge gains as proof positive of your skills, which makes more people trust you in your next pick!

I was excited by penny stocks until I worked this out. I might be a bit wrong in parts, but my magic system tells me I’m pretty close.

I also found this post on Yahoo! Answers to be quite sanity inducing.

Monday, February 01, 2010

HTML5 and O3D

I keep on hearing about the existence of HTML5, and how it takes a big bite out of the need for flash. Here’s a cool (40min) video about the main things in it.

The message appears to be ‘this stuff is all available now, have at it’. Mention of Internet Explorer is strangely missing, but I know IE has at least some support.



Another interesting up and coming technology O3D, which “is an open-source web API for creating rich, interactive 3D applications in the browser”. I looked at a demo, and you write your app/game in JavaScript.

Here’s a (1min) video of O3D in action.


It’s going to be interesting to see where the internet and gaming is in a few years. It looks like we might all be learning JavaScript :)