Monthly Archives: April 2007

McAfee Security Center

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Being an avid blogger, I would like to exercise my huge influence over this internets by publicly declaring how much of an idiot I am for installing McAfee SecurityCenter, which is perhaps the worst piece of software I have ever used.

I’ve been a happy user of AVG Anti-Virus and Sygate Personal Firewall for quite a while but seeing as I got given a 12-month subscription to McAfee, I thought: "Hey, you get what you pay for" and promptly installed it. 

And there the problems began.

  • The time it took for the computer to load was about 20 seconds extra, compared to the previous setup.
  • McAfee failed to work out which IPs were on my local network and I had to spend an evening working out why file/print sharing was no longer working.
  • Every time I turned on the computer, McAfee told me that the Privacy Service had updated and telling me to restart the computer. If I agreed, I would have to wait for the computer to boot up twice before actually managing to get any work done.
  • After an update, McAfee broke and popped up with the error: "Application resources could not be loaded successfully. Please reinstall McAfee SecurityCenter."
  • An uninstall gave "An error occured whilst uninstalling McAfee SecurityCenter." Clicking on the "Close" button caused the uninstaller to crash.

I’m back to AVG and Sygate now, and the only positive outcome of installing McAfee was managing to waste the money of my ISP who provided it to me.

</rant>

Corner.js

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Christian Effenberger created Corner.js which is a really beautiful unobtrusive Javascript to add effects to images in your webpage. It allows you to add corners, shading and drop shadows simply by inserting a small Javascript file into your page and a CSS class.

Christian told me the script was based on Reflection.js. Indeed, the two scripts are very similar: Reflection.js adds a "wet floor" effect typically associated with Web 2.0 whilst Corner.js has some nice image effects which are more "traditional".

Corner.js 

If you’ve used Reflection.js you’ll be right at home with Corner.js – you essentially use it in the same way.

Again, many of the benefits of Reflection.js over server-side processing exist with Corner.js: you can use it with off-site images and forum avatars and you can change the parameters of the corner/shadows by changing just a few numbers rather than having to get Photoshop out.

Kudos to Christian for creating a great script which I’m sure will be another great addition to the toolkit of web designers.

Does anybody else know of any similar scripts which adds effects to images unobtrusively, similar to Reflection.js and Corner.js? 

PHP Fractal Generator

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I was bored so I thought I’d write a PHP script to generate fractals (like you do). The Mandlebrot set is probably the most well-known fractal so I chose to write a script to generate fractals using the Mandlebrot set:

This is a 500×500 fractal plotted for x (real) values between -1.5 and 0.5 and y (imaginary) values between -1 and 1.

How it Works

The mathematics behind the mandlebrot set involve:

  • complex numbers (x+yi)
  • quadratics
  • argand diagram
  • limits

A complex numbers consists of a real component and an imaginary component. i is the square root of -1. A complex number could look like 3+2i, where 3 is the real component and 2 is the imaginary component.

An argand diagram is like a two dimensional number line. With normal real numbers, we can plot them on a one dimension number line, with negative infinity on one end, and positive infinity on the other end. Because complex numbers have an imaginary component too, we need a two-dimensional plane to plot the number.

The Mandlebrot set involves iterating through a sequence:

In words: the first value in the sequence is 0. To find the next value in the sequence, we square the current value and add the complex number (which is the variable). Depending on the input, the sequence will either tend towards infinity or it will remain bounded and oscillate/repeat. If the sequence remains bounded, then it is inside the Mandlebrot set. On my script, I’ve marked these pixels as black.

For those values outside the Mandlebrot set, we use colour to denote how long it takes to reach infinity (in fact we use a shortcut and stop when |z| > 2).

Quadratics come in when we square a complex number – you can just square them as you would with any other quadratic. However, i^2 = -1.

Conclusion

I think it’s pretty amazing how we can generate infinitely complex patterns using such simple mathematics. There is probably only about 10 lines of mathematics in the script; the rest is all PHP/image stuff.

A few notes:

  • The script is pretty server intensive. The source code I’ve provided is configured to produce a 100×100 image by default. This took 2 minutes to execute on my machine, but 5 seconds on my friends machine. Both of them are roughly the same spec. Your mileage may vary.
  • If you try to generate an image with too many pixels, your PC may crash. You have been warned 🙂
  • Try changing the x/y min/max values to zoom or to pan.
  • Feel free to hack the script, rip it apart or do whatever you want with it. It’s public domain.

Green Electronics

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The Greenpeace ranking of the "greenness" of computer companies is interesting and quite a nice way of deciding how "green" the technology you purchase is, especially as climate change seems to have become such a trendy issue recently.

 

Best 5

  • Lenovo – 8.0
  • Nokia – 7.3
  • Sony Ericsson – 7.0
  • Dell – 7.0
  • Samsung – 6.3

Scores out of 10.  Higher is better.

Worst 5

  • Apple – 2.7
  • Panasonic – 3.6
  • LGE – 3.6
  • Sony – 4.0
  • Toshiba – 4.3

Scores out of 10; lower is worse.

 

I’m actually quite surprised that Apple is the least green out of all the technology companies. Apple have consistently come very low on the rankings. Greenpeace on Apple: "low scores on almost all criteria and no progress".

With Apple putting so much of an emphasis on a quality and how "cool" their products are, it’s a shame they’re not taking much notice of the environment. After all, with climate change becoming a hot issue (ha), more and more people are going to be taking notice of these ratings.

It’s also a surprise to see Chinese company Lenovo at the top; just last year, they came last.

Criteria used by Greenpeace for determining how green technology companies are include the chemicals used in products, end-of-life disposal management and the amount of waste equipment recycled.  

Still looking for the Wow

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I gave Windows Vista a go on a secondary computer and I’m still looking for the Wow. It really doesn’t do anything better than XP. The applications that I use are all the same, but I’ve had several problems with hardware working correctly, drivers, UAC driving me up the wall and generally Vista being slower than XP. The learning curve from XP to Vista actually wasn’t high at all; Vista was pretty intuitive. The compatibility problems are the main thing.

I use my computer as a tool – a tool to play games, watch television and videos, listen to music, chat to people and to surf the internet. The two things which are important to allow me to do that are quality of hardware and quality of software. All my software, and all my hardware works with Windows XP. Now the chances are I could upgrade to Vista and benefit from transparent title bars, but it’ll require many hours of work to locate new versions of software, upgrade and resolve compatibility issues.

Costs vs Benefits

On the face of it, £60 for an upgrade to Windows which looks slightly nicer and allegedly has improved security is actually quite attractive. But the monetary costs only scrape the surface. There are many other costs:

  • Time required to create backups
  • Time required to solve hardware, driver issues. Possibly an additional monetary cost in purchasing new hardware or upgrading existing hardware.
  • Time required to find software, updates, subscribe to relevant mailing lists awaiting Vista patches. Temporary loss of productivity in the meantime.
  • Temporary loss in productivity from relearning location of features, etc. 

There is also an opportunity