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This is a little pet project I did a while ago. It’s a FreeCell puzzle‘s solver API.

The idea is to provide a basic validation engine and board management (pretty much like my old chess validation), so people can write FreeCell solvers on top of it. It has basic board setup (of multiple sizes), movement legalisation, and a basic Solver class, which you must derive to create your own solvers.

There’s even a BruteFroceSolver that can solve a few small boards, and that gives you an idea on how to create your own solvers. However, the API is not clear enough yet that children could start playing with it, and that’s the real goal of this project: to get kids interested in solving complex optimisation problems in an easy way.

Freecell is a perfect game for it. Most boards can be solved (only a handful of them were proven – by exhaustion – not solvable), some movements can be rolled back and you can freely re-use cards that have already been placed into the foundations (their final destination) back in the game again.

It’s out of the scope of this project to produce a full-featured graphic interface for kids, but making the API easy enough so they understand the concepts without dragging themselves into idiosyncrasies of C++ is important.

Compiler optimisations

The reason why I did this was to make some of the optimisations compiler engineers have to do more appealing to non-compiler engineers or children with a taste for complex problems. But what does this have to do with compilers? The analogy is a bit far-fetching and somewhat reverse, but it’s interesting nevertheless and it was worth the shot.

Programming languages are transformed into graphs inside the compiler, which should represent the intentions of the original programmer. This graphs are often optimised multiple times until you end up with a stream of instructions representing the source code in the machine language.

Ignore for now the optimisations on those graphs, and focus on the final part: selecting machine instructions that can represent that final graph in the machine language (assembly). This selection can pick any assembly instruction at will, but it has to put them into a very specific order to represent the same semantics (not just syntactic) of the original program. Since many instructions have side effects, pipeline interactions, special flags set or cleaned up, it’s not trivial to produce correct code if you don’t check and re-check all conditions every time. This is a known complex optimisation problem and can be responsible for changes in speed or code size in orders of magnitude.

What does it have to do with the Freecell puzzle? Well, in Freecell, you have a number of cards and you have to put them in a specific order, just like assembly instructions. But in this case, the analogy is reverse: the “sequence” is trivial, but the “instructions” are hard to get.

There are other similarities. For example, you have four free cells, and they can only hold one value at a time. They are similar to registers, and manipulating them, gives you a good taste of how hard it is to do register scheduling when building the assembly result. But in this case, it’s much harder to spill (move the data back to memory, or in this case, card back to cascades), since there are strict rules on how to move cards around.

Reusing cards from the foundations is similar to expanding single instructions into a sequence of them in order to circumvent pipeline stalls. In real compilers you could expand a multiply+add (very useful for digital signal processing) into two instructions: multiply and add, if that gives you some advantage on special cases on special chips. In Freecell, you can use a 9 on top of a 10, to move an 8 from another cascade and free up a card that you need to clean up your freecells (registers).

I’m sure you can find many more similarities, even if you have to skew the rules a bit (or completely reverse them), but that’s not the point. The point is to interest people into complex optimisation techniques without the hassle of learning a whole new section of computer science, especially if that section puts fear in most people in the first place.

Massively multiplayer online role-playing game (MMORPG) are not new. The first I remember playing is the Legend Of the Red Dragon (LORD), but before that, of course, I’ve played other (real-life) multiplayer RPG games as well, and they were never quite the same thing.

Of course, at that time the graphic cards couldn’t quite compete with our imagination (not to mention connection speeds), but a lot has improved in both fronts, and lots of very good looking games have arrived, but still, there’s something missing. For years I couldn’t put my finger on it, but recently I think I nailed the issue: user driven content.

The interface

Most of the MMORGP are war games. World of Warcraft, LOTR online, Vendetta, Star Trek Online, Regnum and so many others rely on war to be fun. Of course, all of them have the side issues, some trade or silly missions, but the real fun is going to the battlefield.

If you look from the technical side of things, this is not surprising at all. Aside from good graphics, one of the hardest things to do in a game is a good interface. Very few games are perfect like Tetris. I gave Tetris to both my sons when they were about 2 years old and after about a minute they were already playing. There is no need to instructions, tutorials or any training and still today I find it quite fun. This is why it’s probably the most successful game in history.

But it’s all about the interface. It’s easy to create a seamless interface for Tetris. Try to create an interface for a strategy game that doesn’t require some hours of training, or an interface for first-person games that actually allows you to know where you are, or an interface for adventure games that doesn’t make you click in half-dozen places to get anything. Many have tried, all have failed.

At the dawn of internet games, strategy and quake were dominant. That’s because the internet wasn’t so fast and both were quite good in saving bandwidth. Quake had a special fix to avoid sending one packet for every bullet and only one packet when you press the trigger and another when you release it, the rest was up to the client.

But in war games, the interface is pretty much established. World of Warcraft didn’t invent anything, they just mixed Warcraft with Lara Croft (rubbish interface, by the way). Space ship games got the interface from Wing Commander (Vendetta got it from W.C. Privateer), Lord of the Rings and Regnum mixed Second Life with old-style RPG (even with the same deficiencies) and Star Trek Online copied from everyone above.

Now, the interface for a good strategy or adventure game is somewhat complicated. For a first-person 3D RPG, even worse. It doesn’t have to be mind controlled to be easy, nor you have to use 3D glasses or any immersion technology to be fun. Simplifying the game is one way, but then it’s even harder to make it more interesting.

It’s the user, stupid!

I can see only one way to add value to a game that is simple but still fun: user driven content.

You can enrich the world in which you’re immersed into. For instance, Zynga is quickly gathering an impressive amount of users by adding a lot of content. I don’t play those games, but people around me do and I can see why it’s so addictive. There are so many things to do and the frequency of updates is so impressive that it’s almost impossible not to be driven to it.

You might think that the games are too simple, and the graphics are average, but the interface is extremely simple, the challenges are simple, yet still challenging, and the number of paths you can choose for your character are enormous. In this case, the user experience is driven by his own choices. The content is so rich that each and every place is completely different from every other, solely driven by user choices.

Not many game companies (certainly not the indie ones) have time or money to do that. So, why are indie games generally more interesting than commercial ones? They go back to square one, simplify the game and optimise the interface. EA would never release something like Angry Birds or World of Goo, and yet those are the two best games I played in a long time. But, world of Goo is over and Angry Birds require constant attention (seasonal versions) to keep selling or making money (from ads).

They are missing the user content. It might not be their style, nor objective, but that’s a difference between Deep Purple and a one-hit-band.

Back to MMORGP

So, from all MMORPGs, there are many good looking, some with good challenges and a lot of slaughtering fun, but I tire quite quickly from playing them. The last I played was Vendetta. Quite good graphically, it has some reasonably accurate physics simulation (what drove me to it) but not accurate enough to keep me playing. The content tires too quickly to be fun after a few hours and even though I had 8 hours of free play, I spent less than two and dropped it.

This was always a pain, since Final Fantasy and the like, building up the character, hitting slugs for XP, fight-heal-run until you level up. Though Final Fantasy was better, as it normally would throw you on level 10 or so, so you didn’t need too much of levelling up. But why? Who likes beating 253 slugs to get 1000 experience points, going to level 2 and being able to equip a copper sword that doesn’t even cut a snail’s shell?

One of the best MMORGP experiences I had recently was Regnum. This is a free game made in Argentina and has a lot of content, good interface and a healthy community. They do the normal quest levelling up technique and it works quite well until level 15 or so. After that, it’s hitting bears, golems and phantoms for half a year until you can go outside and beat other users.

I got outside prematurely (couldn’t bother to wait) and the experience was also not great. Huge lag on big crowds, people disappearing in mid-air and appearing a few meters away, etc. But the most annoying of all was the content. It was always the same fort that we had to protect, always the same keep we had to attack, always the same talk on how our race is superior to your race, etc.

I haven’t seen Lord of the Rings (which sucks on Linux) or Star Trek Online (which doesn’t even run), but I bet they can get a bit further. They’re there to compete with World of Warcraft, not Regnum, but the fate will be the same: boring.

So, after quite a big rant, how would I do it?

User content

First, a memory refresh: all free first-person shooter I know of are a re-make of Quake. They use the same engine, the same world builders, the same techniques. On Debian repositories you’ll find at least a dozen, all of them running on some version of Quake. Nexuiz, Tremulous, Open Arena, Urban Terror, etc.

Not only the Quake engine is open source, but it was built to be extensible and that, even before the source was opened by ID. I made some levels for Doom, there were good editors at the time (1994?), probably there are full development suites today.

The user has the power to extend, create, evolve and transform your game in ways that you never thought possible. To think that only the few people you hire are good enough to create game content is to be, to say the least, naive.

Now, all those games are segmented. Nexuiz levels don’t connect to Tremulous levels. That’s because the mods (as they’re called) are independent. To be able to play all those different games you need to download a whole lot of data (objects, music, game logic, physics settings, etc) and each game has it radically different. Sarge with a rocket launcher would be invincible in most of other quake variants.

But that is, in my opinion, the missing link between short spurs of fun and long lasting enjoyment. I want to be able t build my world (like Zynga), but in a world with free movement (like Quake) with quests (like MMORPGs) made by the users themselves (like no FP-game I know) in a connected world. It cannot penalise those that connect seldom, or those that connect through text terminals, Android phones or browser users in any way.

As some games have started to understand, people like different things in games. I like building stuff and optimizing structures, some like carnage, others like to level up or wait 45 minutes for a virtual beef pie to be ready. You cannot have all that in one game if you’re the only content generator.

Also, if the engine is not open, people won’t be able to enhance it for their particular worlds. It doesn’t have to be open source, but it has to have a good API and an efficient plugin system. Tools to create mods and content is also essential, but the real deal is to give the users freedom to create their versions of the game and be able to connect them all.

If every game is also a server, people can create their small worlds inside the bigger world, that is in the central server. A business strategy would be, then, to host those worlds for people that really cared about them. Either host for free in exchange of ads and content generation, or paid hosting for the more serious users. You can also easily sell content, but more importantly, you can create a whole marketplace of content driven by the users! Read Neil Stephenson’s Snow Crash and you know what I mean.

I think Apple and Google have proven over and over that a market with apps generated by the users is very effective indeed! Intel is just following the same path with their new App store, so yes, this is a good business strategy. But, it’s still fun for a wider range of people, from game addicts to casual gamers, from heavy modders to passive Facebook users.

There are many ways of doing that, maybe not all of them will be successful, but at least from my point of view, until that day arrives, no game will be fun.

I’m not the one to normally do reviews or ads, but this is one well worth doing. Humble bundle is an initiative hosted by Wolfire studio, in which five other studios (2D Boy, Bit Blot, Cryptic Sea, Frictional Games and the recently joined Amanita Design) joined their award-winning indie games into a bundle with two charities (EFF and Child’s Play) that you can pay whatever you want, to be shared amongst them.

All games work on Linux and Mac (as well as Windows), are of excellent quality (I loved them) and separately would cost around 80 bucks. The average buy price for the bundle is around $8.50, but some people have paid $1000 already. Funny, though, that now they’re separating the average per platform, and Linux users pay, on average, $14 while Windows users pay $7, with Mac in between. A clear message to professional game studios out there, isn’t it?

About the games, they’re the type that are always fun to play and don’t try to be more than they should. There are no state-of-the-art 3D graphics, blood, bullets and zillions of details, but they’re solid, consistent and plain fun. I already had World of Goo (from 2D Boy) and loved it. All the rest I discovered with the bundle and I have to say that I was not expecting them to be that good. The only bad news is that you have only one more day to buy them, so hurry, get your bundle now while it’s still available.

The games

World of Goo: Maybe the most famous of all, it’s even available for Wii. It’s addictive and family friendly, has many tricks and very clever levels to play. It’s a very simple concept, balls stick to other balls and you have to reach the pipe to save them. But what they’ve done with that simple concept was a powerful and very clever combination of physical properties that give the game an extra challenge. What most impressed me was the way physics was embedded in the game. Things have weight and momentum, sticks break if the momentum is too great, some balls weight less than air and float, while others burn in contact with fire. A masterpiece.

Aquaria: I thought this would be the least interesting of all, but I was wrong. Very wrong. The graphics and music are very nice and the physics of the game is well built, but the way the game builds up is the best. It’s a mix of Ecco with Loom, where you’re a sea creature (mermaid?) and have to sing songs to get powers or to interact with the game. The more you play, the more you discover new things and the more powerful you become. Really clever and a bit more addictive than I was waiting for…

Gish: You are a tar ball (not the Unix tar, though) and have to go through tunnels with dangers to find your tar girl (?). The story is stupid, but the game is fun. You can be slippery or sticky to interact with the maze and some elements that have simple physics, which add some fun. There are also some enemies to make it more difficult. Sometimes it’s a bit annoying, when it depends more on luck (if you get the timing of many things right in a row) than actually logic or skill. The save style is also not the best, I was on the fourth level and asked for a reset (to restart the fourth level again), but it reset the whole thing and sent me to the first level, which I’m not playing again. The music is great, though.

Lugaru HD: A 3D Lara Croft bloody kung-fu bunny style. The background story is more for necessity of having one than actually relevant. The idea is to go on skirmishing, cutting jugulars, sneaking and knocking down characters in the game as you go along. The 3D graphics are not particularly impressive and the camera is not innovative, but the game has some charm for those that like a fight for the sake of fights. Funny.

Penumbra: If you like being scared, this is your game. It’s rated 16+ and you can see very little while playing. But you can hear things growling, your own heart beating and the best part is when you see something that scares the hell out of you and you despair and give away your hide out. The graphics are good, simple but well cared for. The effects (blurs, fades, night vision, fear) are very well done and in sync with the game and story. The interface is pretty simple and impressively easy, making the game much more fun than the traditional FPS I’ve played so far. The best part is, you don’t fight, you hide and run. It remembers me Thief, where fighting is the last thing you want to do, but with the difference is that in Thief, you could, in this one, you’re a puss. If you fight, you’ll most likely die.

Samorost 2: It’s a flash game, that’s all I know. Flash is not particularly stable on any platform and Linux is especially unstable, so I couldn’t make it run in the first attempt. For me, and most gamers I know, a game has to work. This is why it’s so hard to play early open source games, because you’re looking for a few minutes of fun and not actually fiddling with your system. I have spent more time writing this paragraph than trying to play Samorost and I will only try it again if I upgrade my Linux (in hoping the Flash problem will go away by itself). Pity.

Well, that’s it. Go and get your humble bundle that it’s well worth, plus you help some other people in the process. Helping indie studios is very important for me. First, it levels the play-field and help them grow. Second, they tend to be much more platform independent, and decent games for Linux are scarce. Last, they tend to have the best ideas. Most game studios license one or two game engines and create dozens of similar games with that, in hope to get more value for their money. Also, they tend to stick with the current ideas that sell, instead of innovating.

By buying the bundle you are, at the very least, helping to have better games in the future.

A while ago I wrote an article about Agile and Scrum and wanted to write another one following my recent experience with Agile. However, somehow I couldn’t add anything of that great value to my original post that would be worth a new one.

And now I know I don’t have to. In this fantastic post, Gwaredd takes a deep look into all failures and successes of Agile, with the common misconceptions of believers and decision-makers. In the end, the so called “Post Agile”, is just plain common sense.

Why is it so hard for the game industry to get the online experience? I understand the media industry being utterly ignorant about how to make sense of the internet, but gaming is about pure fun, isn’t it? The new survey done in UK is more than proof of the obvious fact that people will use all resources of the internet to get what they want, whether it’s illegal or not.

After all, who defines what’s legal and what’s not? The UK government already said that it’s OK to invade one’s privacy for the matter of general security, even when everybody knows that any government has no clue on what’s security and what’s not. Not to mention the Orwellian attitudes of certain US companies seem not to raise any eyebrow from the local government or the general public…

That said, games are a different matter. Offline games still need have some kind of protection, but online games should rely on online commerce, and that can only be complete if the user has a full online experience. So, what do I mean by full online experience?

You don’t always have access to your own computer. Sometimes you have just a remote connection, sometimes only your mobile phone or a web browser. Sometimes you have an old laptop with no decent graphic card and those golden times when you have a brand new game machine with four graphic cards. 10 years ago, mobile phones were not as today, but even though my current mobile has a 3D graphic card in it, it’s closer to the lower end when compared to desktops or even laptops.

So, what’s the catch? Imagine a game that you can play exactly the same game irrespective of where you play it.

There are lots of new online games, so called ORPG (online RPG) or the bigger brothers (MMORPG, massively-multi-player ORPG), but all of them rely on a Windows machine with OpenGL2 and DirectX 10 to play it, even though not half of it really need that kind of realism to be fun.

Moreover, when you’re at the toilet and you want to keep playing your battles, you could easily get your mobile and use a stripped down version with little graphic elements but with the same basic principles. When you’re at your parent’s and the only thing you have is dial-up, you can connect via SSH and play the console version. At least to manage your stuff, talk to your friends or plan future battles.

The hard part in all this, I understand, is to manage different players playing with different levels of graphic detail. Scripts on online games are normally prohibited because it eases too much cheating, and that would be the way of battling via a SSH connection… Players with better graphic cards would have the advantage of seeing more of the battlefield than its friends with a mobile phone, or even using a much better mouse/joystick and a much bigger keyboard (short-cuts are *very* important in online gaming).

With the new mobiles and their motion sensor and GPS interfaces, that wouldn’t be a much bigger difference, as you could wave the mobile to have a quicker glance and even use voice-control for some features that is still lacking support in desktop but it’s surprisingly popular in mobile devices. All in all, having at least three platforms: high-end and low-end graphics plus a mobile version, would be a major breakthrough in online gaming. I just wonder why game makers are not even hinting in that direction…

The console version is pushing a bit, I know, I just love the console…