The demoscene first appeared during the 8-bit era on computers such as the Commodore 64 and ZX Spectrum, and came to prominence during the rise of the 16/32-bit home computers (the Atari ST and the Amiga). In the early years, demos had a strong connection with software cracking. When a cracked program was started, the cracker or his team would take credit with a graphical introduction called a “crack intro” (shortened cracktro). Later, the making of intros and standalone demos evolved into a new subculture independent of the software piracy scene.

Prior to the popularity of IBM PC compatibles, most home computers of a given line had relatively little variance in their basic hardware, which made their capabilities practically identical. Therefore, the variations among demos created for one computer line were attributed to programming alone, rather than one computer having better hardware. This created a competitive environment in which demoscene groups would try to outperform each other in creating amazing effects, and often to demonstrate why they felt one machine was better than another (for example Commodore 64 or Amiga versus Atari 800 or ST).

Demo writers went to great lengths to get every last ounce of performance out of their target machine. Where games and application writers were concerned with the stability and functionality of their software, the demo writer was typically interested in how many CPU cycles a routine would consume and, more generally, how best to squeeze great activity onto the screen. Writers went so far as to exploit known hardware errors to produce effects that the manufacturer of the computer had not intended. The perception that the demo scene was going to extremes and charting new territory added to its draw.

Even with modern technology, where much of the effects seen in demos could be replicated in programs like 3D Studio Max, the point of demos are not just the beautiful visuals and music but the abilities of the programmers involved to write code so tight, so efficient, that something might be several megabytes if rendered in a 3D program comes out to less than 100k. So here’s IHC’s favorites from the demo scene of the last few years. These demos are in no particular order, and while we’ve provided Flash video links to each demo, the greatest joy is downloading them (PC only) and giving your graphic cards something fun to chew on.[via I Heart Chaos]

I love Ely’s DragTile component (demo). However, I have always wished that it were easier to extend its behavior to encompass different layouts. To me, that immediately suggests a (big) refactoring. For those of you who have never done refactoring or who don’t refactor as often as you should, I thought it might be fun to walk through this step by step.

What is refactoring?

Refactoring is the process of incrementally changing the structure of your code without changing the outward functionality. It may seem silly to focus on not changing the functionality, but it is actually pretty important.

The idea is that there are two distinct phases of work: coding and refactoring. During coding, you add new functionality. During refactoring, you restructure your code while making sure that it continues to work properly. Not changing functionality during refactoring gives you a strong reference point as you make lots of iterative changes to the structure. You know your refactoring was successful if the new code still does what the old code did.

Refactoring for better reuse

Usually, you refactor code so that it can be more flexible or more reusable that it currently is. Sometimes, the change that is required is obvious. In other cases, you have to think a little before figuring out how to transform your code.

In this particular case, we want to make it easier to change layouts. Looking at the DragTile code, there is quite a bit that would be the same no matter what the layout is, and relatively little that needs to change with each new layout algorithm. Because the layout algorithm is something that is likely to change in various use cases, it is probably a good idea to isolate this functionality into a separate class.

Tip 1: Cleanly separate out the code that you think will need to change often into a separate class.

The most obvious way to divide up the DragTile layout code from the rest of the DragTile code is through inheritance:

Splitting things up in this way allows us to create a new subclass with a different layout (say, a circle) while reusing the logic that might be common to both, such as the code to talk to item renderers and do animation.

The other main way to split things up is through composition:

In this case, the container delegates to another object in order to do layout. There are a number of advantages to this approach:

1. Using delegates often makes it possible to modify behavior at runtime. After we are finished with this particular refactoring, we should be able to change the layout of one of our containers without reparenting. Woohoo!!
2. Decomposing larger classes into smaller classes can make it easier to evolve different parts of the system separately as needs change. For example, let’s say we later decide to split up FlexibleContainer into two classes: one that is lightweight for easy download, and another that is robust, to handle caching, localization, etc. Should “DragTile” inherit from the light one or the robust one? If layout is handled through delegation, you may not need to choose.
3. Composition often allows for greater decoupling. For example, let’s say you are building a photo organizer module. With the inheritance approach above, it would be difficult to create the module in such a way that the photo module knows absolutely nothing about the layout. With the composition approach, you could provide a default layout (say, Tile), while allowing the user of the module to pass in a different layout if needed.

All of this leads to the next tip, which is:

Tip 2: Think hard before using inheritance. Composition is almost always a better way to separate out the flexible part of a class from the invariant part.

So now we have a general idea of what we want to separate out, and how we want to do it. We’ll start digging into actual code in the next post.

[via kuwamoto.org]

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How do you recognise good programmers if you’re a business guy?

It’s not as easy as it sounds. CV experience is only of limited use here, because great programmers don’t always have the “official” experience to demonstrate that they’re great. In fact, a lot of that CV experience can be misleading. Yet there are a number of subtle cues that you can get, even from the CV, to figure out whether someone’s a great programmer.

I consider myself to be a pretty good programmer. At the same time, I’ve spent a fair amount of time on the business side of the fence, filtering technical CVs for projects, interviewing people, etc. Thanks to this, I think I have a bit of experience in recognising good programmers, and I want to share it in this article, in the hope that it may help other “business guys” to recognise good programmers. And, who knows, perhaps some programmers who have the potential to be good but haven’t really exploited this can also read this and realise what they need to do to become good (although, as I’ll argue, that’s definitely not accessible to all programmers!).

In his article The 18 mistakes that kill startups, Paul Graham makes the following point:

“… what killed most of the startups in the e-commerce business back in the 90s, it was bad programmers. A lot of those companies were started by business guys who thought the way startups worked was that you had some clever idea and then hired programmers to implement it. That’s actually much harder than it sounds—almost impossibly hard in fact—because business guys can’t tell which are the good programmers. They don’t even get a shot at the best ones, because no one really good wants a job implementing the vision of a business guy.

In practice what happens is that the business guys choose people they think are good programmers (it says here on his resume that he’s a Microsoft Certified Developer) but who aren’t. Then they’re mystified to find that their startup lumbers along like a World War II bomber while their competitors scream past like jet fighters. This kind of startup is in the same position as a big company, but without the advantages.

So how do you pick good programmers if you’re not a programmer? I don’t think there’s an answer. I was about to say you’d have to find a good programmer to help you hire people. But if you can’t recognize good programmers, how would you even do that?”

I disagree with Mr Graham on this one. I think there are a number of very strong indicators of a “good programmer” (and, conversely, strong indicators of a “not-so-good programmer”) that even a business guy can recognise. I’ll summarise some key indicators and counter-indicators in a list at the end of the article.

#1 : Passion

In my corporate experience, I met a kind of technical guy I’d never met before: the career programmer. This is a person who’s doing IT because they think it’s a good career. They don’t do any programming in their spare time. They’re shocked when they find out I have a LAN and 3 computers at home. They just do it at work. They don’t learn new stuff unless sent on a training program (or motivated by the need to get a job that requires that technology). They do “programming” as a day job. They don’t really want to talk about it outside of work. When they do, they talk with a distinctive lack of enthusiasm. Basically, they lack passion.

I believe that good developers are always passionate about programming. Good developers would do some programming even if they weren’t being paid for it. Good programmers will have a tendency to talk your ear off about some technical detail of what they’re working on (but while clearly believing, sincerely, that what they’re talking about is really worth talking about). Some people might see that as maladapted social skills (which it is), but if you want to recognise a good developer, this passion for what they’re doing at the expense of social smoothness is a very strong indicator. Can you get this guy to excitedly chat up a technology that he’s using, for a whole half hour, without losing steam? Then you might be onto a winner.

#2 : Self-teaching and love of learning

Programming is the ultimate moving target. Not a year goes by without some new technology robbing an old, established standard blind and changing half the development universe. This is not to say that all good programmers pick up these changes and ride the bleeding edge. However, there’s a class of programmers that will never, ever pick up a new technology unless forced to, because they don’t like learning new stuff. These programmers will typically have learnt programming at university, and expect to get by on whatever skills they picked up there, plus whatever courses their company is willing to send them on.

If you’re thinking of hiring someone as a programmer, and he ever utters the words “I can work with that, just send me on a training course for a week and I’ll be good at it”, don’t hire that guy. A good programmer doesn’t need a training course to learn a new technology. In fact, the great programmer will be the one talking your ear off about a new technology that you haven’t even heard of, explaining to you why you must use it in your business, even if none of your staff knows how to use it. Even if it’s a technology he doesn’t know how to use yet.

#3 : Intelligence

Some business people assume that lack of social tact and lack of intelligence are the same. Actually, intelligence has several facets, and emotional/social intelligence is only one of them. Good programmers aren’t dumb. Ever. In fact, good programmers are usually amongst the smartest people you know. Many of them will actually have pretty good social skills too. The cliché of the programmer who’s incapable of having a conversation is just that - a cliché. I’ve been to a few meetings of the London Ruby User Group and I can say that with only a very few exceptions, most people there are smart, talkative, sociable, have varied interests, etc. You wouldn’t look at them chattering away in the pub and think “what a bunch of geeks!” - at least until you approach a group and realise they’re talking about the best way to design a RESTful application with a heavy UI frontend.

This doesn’t mean that they’ll all feel comfortable in every social context. But it does mean that if the context is comfortable and non-threatening enough, you’ll be able to have as great a conversation with them as you would with the most “socially enabled” people (perhaps better, since most good programmers I know like their conversation to revolve around actually useful topics, rather than just inane banter).

Don’t ever hire a dumb person thinking they’re a good developer. They’re not. If you can’t have a great conversation with them in a relaxed social context, they’re very likely not a good programmer. On the other hand, anyone who’s clearly very smart at the very least has a strong potential to be a good or great programmer.

#4 : Hidden experience

This is correlated with the “Passion” point, but it is such a strong indicator that I’d like to emphasise it with its own point.

I started programming when I was about 9, on a Commodore 64. I then migrated onto the PC, did some Pascal. When I was 14 I wrote a raycasting engine in C and Assembler, spent a large amount of time playing with cool graphic effects that you could get your computer to do by messing directly with the video card. This was what I call my “coccoon stage”. When I entered that stage, I was a mediocre programmer, and lacked the confidence to do anything really complicated. When I finished it, I had gained that confidence. I knew that I could code pretty much anything so long as I put my mind to it.

Has that ever appeared on my CV? Nope.

I strongly believe that most good programmers will have a hidden iceberg or two like this that doesn’t appear on their CV or profile. Something they think isn’t really relevant, because it’s not “proper experience”, but which actually represents an awesome accomplishment. A good question to ask a potential “good programmer” in an interview would be “can you tell me about a personal project - even or especially one that’s completely irrelevant - that you did in your spare time, and that’s not on your CV?” If they can’t (unless their CV is 20 pages long), they’re probably not a good programmer. Even a programmer with an exhaustive CV will have some significant projects that are missing from there.

#5 : Variety of technologies

This one’s pretty simple. Because of the love of learning and toying with new technologies that comes with the package of being a “good programmer”, it’s inevitable that any “good programmer” over the age of 22 will be fluent in a dozen different technologies. They can’t help it. Learning a new technology is one of the most fun things a programmer with any passion can do. So they’ll do it all the time, and accumulate a portfolio of things they’ve “played around with”. They may not be experts at all of them, but all decent programmers will be fluent in a large inventory of unrelated technologies.

That “unrelated” bit is the subtle twist. Every half-decent java programmer will be able to list a set of technologies like “Java, J2EE, Ant, XML, SQL, Hibernate, Spring, Struts, EJB, Shell scripting”, etc.. But those are all part of the same technology stack, all directly related to each other. This is possibly hard to recognise for non-programmers, but it is possible to tell whether their technology stack is varied by talking to them about it, and asking them how the different technologies they know relate to each other. Over-specialisation in a single technology stack is an indicator of a not-so-good programmer.

Finally, if some of those technologies are at the bleeding edge, that’s a good positive indicator. For instance, today (November 2007), knowledge of Merb, Flex, RSpec, HAML, UJS, and many others… Please note that these are fairly closely related technologies, so in a couple of years, someone who knows all these will be equivalent to someone familiar with the Java stack listed in the previous paragraph.

Update: As a clarification to this point, there’s in fact two indicators here: variety and bleeding edge. Those are separate indicators. A good variety of technologies across a period of time is a positive indicator, whether or not the technologies are bleeding edge. And bleeding edge technologies are a positive indicator, whether or not there’s a variety of them.

#6 : Formal qualifications

This is more a of non-indicator than a counter-indicator. The key point to outline here is that formal qualifications don’t mean squat when you’re trying to recognise a good programmer. Many good programmers will have a degree in Computer Science. Many won’t. Certifications, like MCSE or SCJP or the like, don’t mean anything either. These are designed to be accessible and desirable to all. The only thing they indicate is a certain level of knowledge of a technology. They’re safeguards that allow technology recruitment people in large corporations to know “ok, this guy knows java, he’s got a certification to prove it” without having to interview them.

If you’re hiring for a small business, or you need really smart developers for a crack team that will implement agile development in your enterprise, you should disregard most formal qualifications as noise. They really don’t tell you very much about whether the programmer is good. Similarly, disregard age. Some programmers are awesome at 18. Others are awesome at 40. You can’t base your decisions about programmer quality on age (though you might decide to hire people around a certain age to have a better fit in the company; please do note that age discrimination is illegal in most countries!).

As a final note to this, in my experience most average or poor programmers start programming at university, for their Computer Science course. Most good programmers started programming long before, and the degree was just a natural continuation of their hobby. If your potential programmer didn’t do any programming before university, and all his experience starts when she got her first job, she’s probably not a good programmer.

Disclaimer

None of the indicators above or below are sure-fire indicators. You will find great programmers who break some of those moulds. However, my view is, you’ll rarely find a great programmer that breaks all of them. Similarly, you may find poor programmers that meet (or appear to meet) some of these criteria. But I do strongly believe that the more of these criteria a programmer meets, the more likely they are to be one of those elusive “good programmers” that, as a business guy, you need to partner with.

The criteria in bullets

So, in summary, here are some indicators and counter-indicators that should help you recognise a good programmer.

Positive indicators:

• Passionate about technology
• Programs as a hobby
• Will talk your ear off on a technical subject if encouraged
• Significant (and often numerous) personal side-projects over the years
• Learns new technologies on his/her own
• Opinionated about which technologies are better for various usages
• Very uncomfortable about the idea of working with a technology he doesn’t believe to be “right”
• Clearly smart, can have great conversations on a variety of topics
• Started programming long before university/work
• Has some hidden “icebergs”, large personal projects under the CV radar
• Knowledge of a large variety of unrelated technologies (may not be on CV)

Negative indicators:

• Programming is a day job
• Don’t really want to “talk shop”, even when encouraged to
• Learns new technologies in company-sponsored courses
• Happy to work with whatever technology you’ve picked, “all technologies are good”
• Doesn’t seem too smart
• Started programming at university
• All programming experience is on the CV
• Focused mainly on one or two technology stacks (e.g. everything to do with developing a java application), with no experience outside of it

I hope these help. Let me know below if you have any comments, or anything to add to them!

Thanks for reading.

Source:http://www.inter-sections.net/2007/11/13/how-to-recognise-a-good-programmer/

We’ve had many a leaked Dell fall into our laps over the years, but this one is already shaping up to be our fave. We don’t have a name, date, or price on it yet, but we can tell you this number is aiming to be 20mm (0.78-inches) thick, with an aluminum extrusion and carbon-fiber chassis — exotic materials rarely found in Round Rock machines. It’ll also have an LED backlit display, but all of the above is still pretty early so there may be changes made before it goes into production — which, by our standards, can’t be soon enough.

[via Engadget]

For those not paying attention, there’s a “leaked” Macworld 2008 keynote making the rounds today, and we’d just like to make sure you know it’s completely and utterly false. Not only is it one of many fabricated keynotes making the rounds this year, and part of an annual ritual of keynote fabrications, but it even manages to be self-damning with its listing of a Mac Pro refresh — which obviously happened last week. Let’s try a little harder, people!

[via Engadget]

On the real, we’re not quite sure we’re ready to sink hard-earned dollars into a digital media “ecosystem” crafted by the same folks working up mobile printers and craptastic portable DVD players, but we suppose we can’t kvetch over any extra competition. Apparently, the firm’s Freescape initiative is based around the Digital Media Exchange (pictured), which stores your precious content and passes it along to other Freescape products — you know, like the accompanying Digital Media Extender, wireless digiframe and wireless PMP. No word on a price for any of this kit just yet, but we’ve all ideas that’s a-okay with the most of you.

[Via Pocket-Lint]

It may not be the biggest name in consumer electronics, but when it comes to stuffing megapixels into ridiculously-skinny packages, there aren’t many out there who do it better than BenQ. Case in point is the new eight megapixel DSC X800, which, at just 9.8 millimeters at its thinnest point (14mm at its fattest), is not only slimmer than the recently-announced DC X835, it even gives the company’s trimmest seven megapixel shooter, the 12.5-millimeter DC X725, a run for its money. Besides its pocketability, however, this model doesn’t offer much in the way of high-end features: 3x optical zoom, 3-inch LCD, digital image stabilization, VGA movie mode, and a rather non-standard microSD slot are par for the course here. Keep reading after the break for another angle / color combo of the as-yet-unpriced shooter, which should be shipping sometime this quarter.

[Via Slashgear]

In a piece primarily focused on Blu-ray over at Business Week, a bit of scrolling led to quite the interesting tidbit: Sony has apparently been able to slash the production cost of its PlayStation 3 in half. More specifically, it was noted that the firm has been able to “shrink the PS3’s chips and tweak its design,” which aided in getting the cost per machine “to around $400 now, from above $800 just before it went on sale in November 2006.” According to Nikko Citigroup’s Kota Ezawa, the biggest culprit for such an improvement is the “reduction in the parts count.” Still, we wouldn’t get our hopes up for yet another price cut just yet, but at least things are moving in the right direction.

[Via PS3Fanboy]

Phiaton — not to be confused with Volkswagen’s futile attempt to break into the luxury sedan market — is setting out to grab dollars from audio geeks that have a thing for style. The firm is actually part of Cresyn, and is attempting to put its name on the map by introducing four new exotic looking headphones, a pair of oddly-designed earbuds and a vivid music docking station. Regrettably, there are no prices to share on any of the aforementioned gear, but if you’ve ever secretly craved cans wrapped in faux alligator skin, this company is sure to impress.

[Via CNET]