Quantumstate’s Blog

Piracy is becoming more widespread. There are many different things which are pirated via computers however I will just look at software. Open source software does also seem to be growing in popularity but more slowly than the growth of piracy.

Does piracy have a negative effect for open source software? I think it probably does. First we should look at what attracts people to open source software, what its benefits are.

First they will be attracted if the software is good. Firefox is a good example of an open source program which became popular because it was well made and better than Internet Explorer. People will recommend software to each other if they find it good.

The other major factor is that it is free. Free in the sense that it costs no money. Most users don’t know the difference between freeware and open source software. There will be a few idealistic people but these are a small minority.

I will ignore the quality for now because that isn’t really affected by piracy, at least not in the short term. In the long term lack of money could make a difference to quality but I will ignore this.

Piracy makes commercial software available for free. There is a small risk of being caught which will deter some people who don’t want to break the law, but it is not a very serious risk. So this removes one of the major advantages that open source software gives. So I would imagine that piracy is having a negative effect on open source software’s acceptance.

Yesterday I went to see a couple of Christmas lectures with my school. There was both a maths and a chemistry lecture. Both lectures were pretty good and they definitely made me look forward to what university might be like. Of course it is hard to tell because they covered some of the more fun content.

The chemistry was in the morning and was done by a couple of chemists from Southampton University. They did plenty of fun experiments. They started off with cryogenics so they had the dry and and liquid nitrogen to freeze things with. They lit a balloon full of oxygen and helium to show us a fast reaction which was pretty loud. Also they showed us some things which glowed. You really need to see things like this to appreciate them though, my description definitely doesn’t do them justice.

The Maths lecture was by David Acheson from Jesus College, Oxford. His talk was really interesting, he showed us some interesting proofs and little mathematical tricks. He has a website which has some of the things that he showed us on it. The programs that he has on there are quite fun to look at and fairly informative. He also plays the guitar and so he played a bit to us, he says that otherwise he wouldn’t get to play it to anybody.

Just to finish off here are a couple of the puzzles that he gave us to do over the interval. They are fairly common puzzles so you may have heard them before.

What is the value of sqrt(1+sqrt(1+sqrt(1+…))) with the square roots going on to infinity. The answer is best left in surd form since then it si clear you haven’t just used a pocket calculator.

If a spider is in the corner of a 1×1x1 cube and the spider wishes to reach the opposite corner how long is the shortest route. The spider can walk anywhere on a surface but cannot fly.

I have now made an update to my physics engine. I have put in some basic collision detection which is rectangles only so far so there will be no circles in sight this time. The balls change colour when they collide, I put this in for debugging and I thought it looked pretty so i haven’t bother to remove it from the display.js file.

Also there are different size square now (rectangles also work but I prefer squares). Also they actually bounce off the right hand wall rather than bouncing off something just past the right hand wall. In my example there is no check to see if the squares overlap at the start and the collision detection can’t handle the big overlap so if you get this refresh the page and hope you don’t get an overlap.

At the moment the collision detection is fairly crude because it just handles rectangle to rectangle. I have planned out a few algorithms for circle-circle collision and more advance square-square collision which should work with rotated square.

If you come across any bugs please tell me. I have found some bugs that have been quite rare when I was testing before (one happened when the squares collided so that the corners hit each other) so I may bot have picked some of them up.

http://www.quantumstate.co.uk/physics/physics2/