Ranger Sheck's Blog

There are a lot of good resources out there for Procedural Content Generation. The PCG wiki lists a ton, and if you’re looking to read up on the subject, it’s a great place to start.

A lot of these ideas are derived from the original Nethack game (and predecessors like Rogue and Angband). As the PCG wiki says, there are two basic methods to dungeon generation: you either start with a bunch of rooms and then connect them, or you start with solid rock and carve out a maze.

As you might expect, implementations of the first method are more widely used. I’ve been playing Chocobo’s Dungeon off and on for a while now (over a year, I guess), and whenever I play it I start thinking about procedural generation. It’s quite obvious that the dungeons in Chocobo’s are a bunch of standard room shapes randomly scattered about a floor and then connected via corridors.

There is a code sample and live demo (in javascript) linked toward the end of this article, but if you’re impatient and you want to see what the heck I’m talking about, here is the demo!

Starting with the Rooms

In some cases, the shapes of rooms might themselves be randomly derived. I noticed that in Chocobo’s, there were some definite pre-created room shapes. I decided to try it that way myself. I created a couple of text files to store each room-shape’s data. I used a simple, arbitrary code for “drawing” the rooms with characters:

character	stands for
W	walls
f	floors
+	possible connection points
(space)	empty space

An example room:

W+WWWWW
Wfffff+
WfffffW
WfffWWW
WfffW
+fffW
WW+WW

Toss some Rooms together, one Row at a Time

At first it’s tempting to be really random when throwing rooms together. Most of the time, however, we want our rooms to collectively fit into a nice neat square or rectangle. Personally, I don’t want my rooms too spread out either. Which lead me to the next temptation – just create a grid and put one room in each cell of a grid. I think you can already guess how boring that might look. It’d be like someone built a dungeon on a tic-tac-toe board.

So I’m going for a compromise. First, I start with an arbitrary size limit – like: 30×40. Then I take things one “row” at a time – and by “row”, I mean a row of rooms. I pick a room at random, stick that into a list. I keep track of how much x-space (width) this room is taking up out of my maximum. I pick another random room (narrowing my list down to only rooms that will fit in the space remaining – adding 3 units to account for corridors in between), add it to the list, add up the total used space, and so on.

What I end up with is a handful of room shapes. I randomize the order of my list and start placing them in a row – as if I’m sticking objects side by side into a box – taking care to pad the breaks in between with 3 units to make sure there is minimum room for a corridor. Then I figure out the leftover horizontal space on the end of the box. I redistribute that space randomly throughout the whole “room row”, causing rooms to space out from each other a little if there is extra room.

At this point, the room-row is as tall as the tallest room. I can now shuffle the shorter rooms up and down randomly. Here’s a sample room-row:

W+WWWWW              WWW+W
Wfffff+   WWW+WWW    WfffW
WfffffW   Wfffff+    WfffW
WfffWWW   WfffffW    +fffW
WfffW     +fffffW    WfffWWWWW
+fffW     WWW+WWW    Wfffffff+
WW+WW                WfffffffW
                     W+WWWWWWW

Then we move on to another row of rooms, and another, as long as we have space to accommodate them. The key to keeping this as un-grid-like as possible is variations on room shapes – particularly, variations on widths and heights. Try making rooms that are large, small, long, tall, L shapes (pointing in various directions) and other interesting shapes.

Connecting Rooms with Corridors

There are a few different ways to go about generating corridors. You can specifically try creating them room by room, ensuring that every room is connected to at least one other room; the benefit of this method is that you never have to worry about having a map split into two segments, unreachable from each other.

I decided to go another direction though: almost totally random connections. The side effects of method are: a) you are not guaranteed that all rooms will be connected – you have to do some kind of test (like a flood fill) at the end and discard your dungeon if not all floor tiles are reachable; and b) you get some interesting results where rooms might connect to themselves by an external corridor across one side. I liked this second side effect, since it adds just a little less predictability to the process, so that’s why I’m doing it this way.

First, I find what I call the “nubs” of every room. These are the points out in space, just off the connector points that I used a ‘+’ to designate. I find each ‘+’, then ask “where is the blank space from here”? In other words, from the (x,y) of the ‘+’, I try N, S, E, W until I find the coordinates that have just a space (rather than a ‘f’ or a ‘W’). Then I take a random ordering of the “nubs” and for each one of those, I try connecting it randomly to every other. I check to see if a corridor could be drawn by first checking to see if a rectangle could be drawn, with each nub as a corner. If I can draw a rectangle without crossing any other filled coordinates, then we go ahead and make a corridor.

Drawing a Corridor

Making a corridor is pretty easy, really. You have a start point and end point. First, you have to determine which x-direction and which y-direction you need to go. For example: if your start is 2,3 and your end is 6,7, then you need to go positive in both x and y. If your start is 2,7 and your end is 6,3, then you need to go positive in x but negative in y. Then we randomly decide – either step in the x direction or step in the y direction. Each step we take, we make sure not to go over the ending x or y. For example, if we reach the x destination, then we stop picking x or y randomly and instead just step in y direction the rest of the way.

W+WWWWW          
Wffffffff WWW+WWW
WfffffW f Wfffff+
WfffWWW ffWfffffW
WfffW    fffffffW
+fffW     WWW+WWW
WW+WW           

an example of a randomly drawn corridor

Notice that we didn’t bother with the walls – we’ve only mapped out the floor tiles between the start and the end points. After the floor is drawn, we can add walls by cycling through every floor tile and checking N, S, E, and W of each one. If there is a blank tile next to a floor tile, turn that blank into a ‘W’. Finally, we replace any unused ‘+’ tiles with a ‘W’ as well.

Code Sample and Live Demo

I wrote this code originally in Ruby, since it’s going to become part of the code-base for Aethora (no, you won’t see these kinds of dungeons in Aethora, but you will see a spin-off: a more “dungeon crawler RPG” type of game, less “tactics/strategy” type of game). I’ve taken the time to rewrite the algorithms as javascript so that I can demonstrate it easily on a web page and that more people will be able to dig into it and read it (admitting that more people are familiar with js than ruby).

Requirements for this code: I used jquery this time, so you’ll need that I’m using 1.4.2). I’m also using the small but awesome lowpro library, which allows for an object-oriented style way of writing behaviors for events on elements. This library was extremely useful when used with prototype, since prototype lacks the handy “attach” functions that jquery has, but I still find it nice for jquery because it allows me to organize event handling in a clean way.

If you view the source on the page (that I’m about to link to) you’ll notice a couple of other js files that I’ve created:

• array.js – just a few helper methods for bastardizing the Array prototype to include sum, max, and min
• room_template.js – a simple object class for encapsulating those room shapes that we set up in the beginning
• mapper.js – an object class used to encapsulate the map generation functions

You’ll also see a small block of js in the source of the index file where RoomGenerator is defined – that’s the lowpro behavior. We just attach it to the “generate” form.

The room shapes are in textareas, so go ahead and tweak them if you want. Also you can play with the dimensions – I’ve given you a starting size of 30×30, but put in whatever you want. Use at your own risk!

Procedural Dungeon Generation Demo

One more note – notice that in this demo, we’re not checking to make sure all the rooms are connected. In my real code, what I do is: first generate a dungeon. Second, make a copy of the dungeon. Grab a floor tile of the copy and replace it with an ‘X’, and flood-fill out from there, replacing all f’s with X’s. Then I loop through the copy and make sure there are no f’s left. If there are, then I know those floor tiles were unreachable by flood-fill, and therefore unconnected. I toss out the dungeon and generate a new one (no, it doesn’t really take long to randomly generate these dungeons; a few milliseconds is all). Another option would be to somehow look for a way to force a connection between any disconnected rooms, by just finding any ol’ space where a corridor might fit.

Bonus Round: Converting ‘f’, ‘W’ into images

We’ve covered the generation of the rooms and corridors. If you’re making a text-based game, then just using ‘W’ to designate a wall works just fine. But if you want to convert those walls into image tiles, you’ll want to figure out how to place corners, horizontal walls, vertical walls, connecting walls, and so on.

To simplify this task, I decided to name my walls based on the directions a wall tile connects to other walls. Some examples:

WW
W

The first tile is a corner wall. It connects to a wall to the South and a wall to the East. It’s image name is wall_s_e.
The second tile connects only to the West: wall_w
The bottom tile connects only to the North: wall_n

WWW

The first tile only connects to the East: wall_e
The middle wall tile connects to the East and to the West: wall_e_w.
The last tile connects to the West: wall_w

It may seem a little backwards at first – because you think a wall is sticking out to the South, but it’s connecting to the North, so we call it wall_n instead of wall_s. There is a reason for doing it this way – it’s much easier to write code to detect which directions walls connect in than which directions they “stick out in”.

So anyway, it’s just a matter of looping through all the wall tiles and then checking: do I have a wall to the North? do I have one to the South? East? West? Okay, on to the next wall tile.

Before you know it, you’ve turned your W’s and f’s into tiles:

click the image for a larger version

Well, that’s all for today. If you have any questions, don’t hesitate to ask. I’m too lazy to put a license in the js code itself, but you can consider it licensed under MIT (so do whatever you want with it; credit would be nice, but not required). If anyone has the time to port this code to PHP, Python, perl, .NET, or whatever, please let me know. I can provide a ruby version on request, but if you’re patient, I do plan on releasing a whole giant chunk of the Aethora code base (which is Ruby on Rails) as open source.

Over the last several months, I worked out a whole new interface for Aethora’s battle screen. I’ve learned a lot about javascript in the last couple of years since the original design, and I felt that it was about time to scrap the whole thing and rewrite it from scratch. I’m breaking this article into two parts. The first part here will touch on what was wrong with the old interface a little, and then focus on performance improvements. The second part will focus on “point and click” interface improvements.

Beef with the original

The original design drew the battle map by actually drawing a huge table and putting a map tile in each cell. At the end of every turn, any NPCs that needed to take their turn would do so while the player sat and watched a big “Loading…” box, then the whole page got redrawn, the server globbing a huge amount of HTML back to the browser. The only evidence that any NPCs took their turns was in the battle log.

When you wanted to take an action, you had to first highlight a target. It was like a MMORPG – target first, then act. When you targeted someone, you’d get a list of valid actions depending on whether they were friendly or not, how close you were, and how many Action Points you had left. Some players reported that they often moved PCs one tile at a time, inching their way closer to see when they would be just in range for certain attacks. Many players complained that area-based attacks could not be placed in the center of a group of targets unless one of the targets happened to be standing dead center.

The old interface also featured a bunch of tabbed components to the right of the map. They held, individually, information about the character who’s turn it was, the help screen, the chat screen, the battle log, and the “turn order” screen (which showed all the PCs and NPCs in the order in which they get their turns, each with health and defense bars). Tabs are a great way to group UI elements when you are dealing with multiple pages of configuration, but when they hide elements that players want to see constantly, then they just become a nuisance. In particular, not being able to see the battle log and the full list of PCs/NPCs with their current status was a common player lament.

Setting the bar

I had a couple of goals for the rewrite:

• no full screen page refreshing
• show the player what the NPC are doing during their turns
• minimize the amount of HTML needed
• separate the javascript from the server-side code in a way so that either could be used without the other (having the mindset of an open API)
• fit all the elements onto one compact screen with no tabs hiding information
• improve the user interaction (moving characters and taking actions)
• keep everything as generic as possible to lay the groundwork for PvP/Co-op in the future

The first couple of goals kind of go together. What they amount to is a whole lot of javascript. I took advantage of the object-oriented aspects of javascript and roughly mapped some of my server side objects to javascript objects. When the battle window first opens, some HTML sets up the framing of the layout, and then a couple different ajax calls are made: the map tiles, the “mobs” (short for “mobiles”: in other words, PCs and NPCs), the chat log, the battle log, and the actions that are available for the PC with the “current turn”. Each of these calls fills in a different part of the screen (and actually, the actions-load doesn’t trigger until after the mobs are loaded in).

From this point, I can update any individual components as they are needed. When someone moves their character, the only thing that needs to be reloaded is that mob’s stats: to reflect the deduction of movement points and to set their x,y location on the map. If they take an action against another mob, then both of those mobs need to be updated. In both these cases, the battle log also needs to be updated.

Smaller bites of AJAX – or as the kids say these days… AJAJ?

All of these updates are AJAX calls, although as many people have started to point out, AJAX is not always Asynchronous Javascript and XML. In this case, I, like many others, have set aside XML and opted for the much leaner and easier to read JSON data format. So a request is made to the server, the server does some database lookups and some processing, then sends back a pure data response in JSON form. The javascript then takes the data and decides what to do with it. Since the calls are “asynchronous”, the javascript doesn’t have to wait for all the calls to come back to deal with the data; it can start updating the battle log when that data comes in and if the mob data gets in at the same time, it can process that too, more or less simultaneously.

The bonus of this strategy is that calls to the server are extremely short. The server only looks up a small amount of data and slaps it into JSON format on each call. The side effect is that there are more calls to the server. Would you rather have multiple short requests, or single, large requests on your server? If you’re concerned about connections, you might feel as though single large requests would be a better option. However the advantage to many short requests comes in during optimization.

Bastardizing the server-side code

I haven’t mentioned it to this point, but the server side code I am using is Ruby on Rails. I love Rails for the flexibility it gives me in developing database-backed web applications (insert your own favorite ORM / MVC web framework here – I’m not biased against any, I just happen to like Ruby a great deal). Where Ruby and Rails fall behind is on performance. A Rails server uses up huge chunks of memory, and this limits the number of requests it can take at one time.

When Rails runs in development mode, you can watch the log files and take careful note of the database calls that are being made. This feature allows me to look at each of the requests being made one by one and determine that – if somewhere in all those layers that a web app might have – unnecessary hits to the DB are being made. It also allows me to grab those DB queries and throw them into an EXPLAIN statement so I can determine if indexes are being used. Then I can simplify my Rails code and optimize my DB queries as necessary, to maximize the speed of each of those individual AJAX calls.

And finally, as a major bonus – I was actually able to take some of those simplified queries and plug them into a few lines of PHP. Yeah, that’s right – I can run both Rails and PHP on the same web server – there’s no law against it! So, for example, the battle log – these requests are made constantly while an NPC is taking their turn, so the player gets the impression that they are watching the turn unfold in real time. There is nothing secret in a battle log – no user information or anything. It really is just about grabbing a couple rows of log data and a couple fields of mob data. Using ApacheBench to do a quick speed test, the PHP calls are a little faster than the Rails calls to get the same data. Punch up the number of concurrent connections, and you really start to see a difference: with 5 concurrent connections, the PHP script time was about 2/3rds that of the Rails time. The number of simultaneous Rails processes is limited by memory usage, whereas Apache can fire off PHP scripts by the gobs.

One important thing to note if you’re going to run multiple server-side engines to respond to AJAX calls: be careful not to violate same origin policy. If you need to run different server-side code under different subdomains, make sure to set document.domain (as described in those articles). I’m using the wonderful passenger module, which allows me to run Rails straight out of Apache. In this setup, Apache can bypass Rails to get anything out of the public directory (for images, CSS, javascript, etc). If it finds a php file in the public directory, well then, it’s business as usual. That way I can have: http://mydomain.tld/something/from/rails and http://mydomain.tld/minicall.php – same domain, different server side processing!

That’s it for the performance improvements – I’ll come back and give you another article that focuses on the point-and-click interface improvements.

Been a while since I’ve posted, so I thought I’d at least mention what’s happening in Aethora right now.

We’re currently running an event called “Pioneers Week”. Here’s the short description:

Pioneers Week is the time when people all over Hopilus celebrate the anniversary of the discovery and colonization of their continent. They honor the struggle and the achievements of their forefathers, and due to this great attention to the past and its protagonists, the flow of ather itself shifts, temporarily, creating echoes of those who have lived and worked that walk around in places where they worked and acted.

You can find these echoes – ghosts, as some call them – although you have been told they are rather weak echoes, and that there are more powerful, permanent and natural ones all over Hopilus. All towns have some old town square or town hall where the first colonists of that town appear, and on the roads you may be challenged by others, who are remembered for traveling, and like a challenge or who have failed, and are resentful for it.

The event lasts one “week”, which really means two weeks. This is the second event we’ve done in Aethora, and I think it’s going … well, it’s going ok. One goal we have with events is to make them challenging. The skill system in Aethora gives us the chance to introduce new NPC-only skills just for an event, which really levels the playing field and even the most maxed-out players will find it challenging. Unfortunately, we are finding that we may have made the event a little too challenging. Some players are getting frustrated. The dedicated players know that if they stick with it, and start with the lower level areas and work their way up to the harder stuff, they will enjoy it. However, I think more casual players are turned off by the scenario. If they have played enough to be high level, they tend to start playing the event in the high level areas and then are quickly lambasted by the event NPCs.

So what have we learned from this experience?

Well, for one thing, we’re not going to add event-only “roamers” to the world next time. They can be a real pain in the neck for players – those players that logged out in a high level area, come to the event, and then want to travel back to the low level areas to train up have a chance of being jumped by roaming event NPCs surrounding those high level areas. As you can imagine, players find this a little irritating, because these NPCs are extremely tough. And, as my lead designer put it – not everyone likes being forced into an event.

Secondly, we’re thinking the event should be more focused – in other words, it should have a clearer goal. Perhaps centered around a certain mission or something. We like for certain aspects of the event to be repeatable, so the hardcore players can enjoy it fully, but I think casual players might appreciate achieving a sense of accomplishment by finishing the main “mission” of the event. In our current event, there are two “mini-missions”, but they are really just set-ups for single encounters with rewards for their completion.

Lastly, while an event is great fun and gives us a chance to flex our creative muscles, perhaps even introduce some humor and temporary silliness to the game, we know that “real” updates to the game would probably be more attractive to our player base at this point. Initially, we had hoped that doing a few events would be an easy way to crank out some temporary content to keep players interested in Aethora. Unfortunately, the work behind an event actually takes a lot more time than you might think.

The good news is that we’ll be able to re-use the work that we’ve done and bring two events back each year, with some improvements. In the meantime, it’s time to get back to work on more permanent content and code updates!

If you’ve ever personalized a Google home page, you’ve seen the various gadgets that can be added. These gadgets can also be placed into other web pages, blogs, and so forth pretty easily, and they share a very similar framework with “gadgets” in other sites, such as MySpace’s new MySpace Apps. In this article, I’ll show you how to make a simple gadget that pulls dynamic data from your game and displays it in a nice little box.

Read the rest of this entry

Continuing from Game Design Principles – Part 1.

Game Design Principles behind Aethora (5 through 9 of 9)

5. Good strategy should mean combining lots of different skills. The appearance of a successful strategy that utilizes only one or two skills is an indicator of imbalance.

Everyone who’s ever played a MMORPG knows that balance is always an ongoing issue. The developers are always making adjustments to classes, abilities, equipment, and so forth. The sheer quantity and variety of factors that are involved make the concept of total balance something that’s impossible to achieve during the design phase. You can get pretty close, but one thing a designer has to remember – you design aspects of the game with certain intended uses, and the balancing you provide is based on those intended uses. When players get ahold of the game and start using things in ways you didn’t intend or anticipate, you’re going to discover new imbalances. It’s a fact, Jack.

So one easy rule of thumb that I’m using here, somewhat specific to Aethora, but in general I think a good strategy: If I notice that a player is gearing up all their characters with the same gear, then I can guess that they think they have found an attack or two that is far superior to other attacks. Sometimes, this strategy is a bad one. Other times, the player could be onto something – there may be an attack that makes a battle much easier to win and other attacks are inferior by comparison.

The overall point is, at least for Aethora, the game is party-based. A good party in any RPG should have some variety. Characters tend to fill different roles, such as melee, magic-user, healer, and so forth; or in common MMORPG-speak: Tanks, DPSers (damage-dealers), Buffers, Healers, Crowd-Controllers, and various other “Support” roles. So, in Aethora, I want to see the good players using a broad mixture of skills in combat.

6. Victory in combat on average should be decided by factors in this pecking order: Good strategy > Higher Skill Levels > Better Equipment

Aethora is a tactical, or strategy RPG. Party-based combat on a map is the core of combat, so I try to spend some time thinking about what makes map-based combat fun and challenging. I like to think of a tactical RPG almost as a game of chess; but instead of simply different move-patterns, the pieces have different offensive and defensive abilities. Since the game at it’s core is still a role-playing game, the whole point is to advance character development; so character skill levels should, of course, make a difference when it comes to combat. The secondary method of character development in an RPG has to do with acquiring better equipment, and clearly a well crafted longsword should outperform a rusty fire poker.

So the goal of this principle is this: good equipment is no substitute for adequate skill levels, and skill levels are no substitute for good strategy. In other words, a player should still have a chance to win a fight in which they are outclassed in terms of equipment and skills, to a certain degree, as long as they employ good strategy. Likewise, if a player has a poor strategy going into a fight, expensive equipment will not save them.

To achieve the “Higher Skill Levels > Better Equipment” part of this principle, there is some real basic math going on. The combat formula uses some weighting to give advantage or disadvantage between attacker and defender skill levels, and then a lesser weighting when comparing attacker’s weapon strength with defender’s armor strength. Making “Good Strategy” the most important factor in combat is a little trickier, and it relies pretty heavily on principle #5.

7. No “punishment” paths in missions (quests). Any path that “burns a bridge” should be roughly equal in benefits to any other path.

Mission-writing has been a primary goal of our development team in the last few months, so I felt it necessary to lay down this particular ground rule. It’s very tempting to create a branching point where a player can chose to do the “right thing” or the “wrong thing”; after all, decision making is part of the challenge of doing quests or missions. So if a player chooses the “right thing”, maybe they get a little more gold in the end, or even a better piece of equipment as a reward; and that makes sense. However, it makes me a little uncomfortable to see a situation in which a player might do the “right thing” and gain access to another mission later on, where the player who picks the “wrong thing” ends up at a dead-end.

Mainly this principle has to do with Aethora being somewhat of a “casual” RPG. I’d hate for a player to become frustrated and quit because they missed out on something when they took the wrong path – especially when the decision was tricky (and often these things are not obvious). Since this is an online game, and not a single-player game, there is no previous saved game to reload when you make a mistake.

So I devised a simple formula for “factors of mission outcome equality”: Chance for another mission = 100; unique piece of equipment = 10; monetary reward = 1

In other words, two branching mission paths that both offer another mission are roughly equal (100 vs 100). Two branching paths in which one offers gold but the other offers equipment are close enough to equal (10 vs 1). Branching paths in which one offers a new mission but the other offers only one piece of equipment are not close enough to equal (100 vs 10). But, if you really want to write two branching paths and let one lead to a new mission and another lead to a bag of unique equipment (like say 8 pieces, or 100 vs 80), then I’m more likely to allow such a choice (as long as the storyline makes sense, of course).

What we end up with is less chances for “right” and “wrong” paths and more paths that are just “different” – and I’ve found that these can be much more interesting. You can see that I’ve made an assumption here that what players want most of all is to do more missions; I think for the majority, that’s part of the fun of the game. Completing a quest or a mission is an accomplishment. Therefore, a chance for another mission outweighs material rewards many times over.

8. The best RPGs incorporate fun and engaging gameplay as well as quality story lines. These are two dimensions on one grid; to cover the maximum amount of area possible, both dimensions need to be stretched.

At this point, I’m going to take a moment and re-iterate that these principles are largely based on my personal opinions when it comes to role-playing games. The first part is easy: if gameplay – and by that, let’s be frank, I’m mostly referring to combat – is weak, then I’m not going to play a game. Combat needs to be interesting, engaging, should not feel overly formulaic, should not be too long and should not be too short. That’s a pretty tall order to live up to, but remember, this is a principle – an ideal – I’m aiming for. I’m not claiming that I’ve reached it 100% with Aethora.

To be honest, if the gameplay of a particular CRPG is pretty good but the storyline is inane, there’s still a pretty good chance I will play the game. Let’s face it – storylines in CRPGs for the most part are pretty thin, so players have learned to deal with it. That being said, when I look back on my most memorable experiences with CRPGs, the games that had great storylines stand out the most.

So you see, these two factors can combine to make a great game. However, it’s my opinion that you’ll lose people quicker if gameplay is weak. If gameplay starts out good but becomes tedious later on, you may lose more people that way as well. Ranger Sheck’s inner voice: “If you want people to play the game, you better make the game fun to play.” But, then, I love to write, and I know how memorable a good storyline can be, so with this principle I’m recognizing that good stories are going to help make a mediocre game reach for greatness.

I’m willing to bet some developers (especially browser-based games, where text is easier to work with than graphics) are going to disagree and claim that a good story should carry the most weight. I love a good story! And for that reason, I do a lot of reading. A lot. Even the best storyline in a game cannot come close to a good book, and so when I want a good story, I don’t want to sit in front of my computer screen and read page after page – I’ll sit down with a good book. That’s why it’s my opinion that quality writing can greatly enhance, but not carry, a CRPG.

9. There is a third dimension that is unique to online RPGs: player community and interaction. While more difficult to stretch, this dimension bears much greater potential.

This last principle expands on the previous one, to serve as a reminder of why “online” role-playing games are different than offline CRPGs. Aethora needs a lot of work in this area, because other than buying and selling equipment to other players and some sharing of information through chat and forums, there isn’t much other player interaction. I recognize the fact that having a more interactive community really has a profound effect on the popularity and “stickiness” of an online RPG. Therefore, this principle is here at the bottom, not because it’s the least important, but the one that Aethora needs the most work on.

I have some big plans in this area, and I just need to find some time to work on them: – Player crafting and tradeskills to increase market trading between players. – Contests and tournaments where players can face off against similar groups of NPCs and see who does the best – Player versus player combat (I’m still on the fence about this one, as the nature of a web-based game introduces a lot of potential issues) – The ability for players to own land and populate land with guardians – even to the point at which a player might create an entire “dungeon”, populate it with baddies and treasure and then invite other players to come try their hands at it. My ultimate goal, to put it simply, is to have ways for players to generate content.

Well, that about wraps it up. Comments? Questions?

A couple months ago, I made the change from being the sole developer and writer for my game and invited some of my players to join me in creating a design team. While all the coding responsibilities still rest on my shoulders, the other designers have been contributing artwork, mission plots, non-player character design, weapon and armor design, area design, and so forth. I quickly realized that while it’s possible for people to get a sense of what a coder’s thoughts and motivations are by playing their game, there are still many aspects of a game’s design that are not so easy to interpret.

When I set up a forum for our team to collaborate in, much of the initial conversation was brainstorming about changes or additions to make to the game. I found myself defending and explaining various methods and components of the current design and what those explanations meant for future design. I realized that while I am open to other ideas, there were certain things that I wasn’t likely to budge on. The more I thought about it, the more I began to understand that I had internalized a set of principles that guide the path of development for my game.

Do I think all games should follow these design principles? Certainly not! Many parts of this list were born out of being unhappy with one particular aspect or another of a game that I otherwise enjoyed; some other parts were born out of recognizing which parts of existing games I think were done really well. But without a wide diversity of drivers and factors behind game development, where would we be?

So you may agree with these principles, and you may not. The perspective they are written from lies in the development of a role-playing game; specifically a computer role-playing game (CRPG), and more specifically than that, an online, web-based, strategy (or tactical) role-playing game. To date, combat is the largest aspect of my game, and since it is a tactical RPG in terms of a combat system, some of these principles might only make sense in that context. Others, however, are more universal.

As you read these, please take note: The words are mine, but the thoughts behind them come from an accumulation of years of experience in playing, thinking, and talking about games. I don’t claim any kind of exclusivity or originality on any of these concepts.

Game Design Principles behind Aethora (1 through 4 of 9)

1. No wrong path for character development.

This principle is at the top of the list for a reason – it’s the one that was the foundation for the character system in Aethora. This character system, while not 100% unique, is very rare in the broad range of RPGs out there, because it is classless. In a role playing game, you need roles, and in most games this role is chosen from the start as a job or a class. In some cases, it can be changed or it has branches later on in a character’s development. In Aethora’s case, the character has no class, but simply a set of skills. There are no levels, no experience, no points to spend. When you want your character to learn how to fight with a sword, you have to put a sword in their hand and get them to battle. The more you use a skill (against better and better enemies) the better you get.

The big seeds for this principle are in my frustration with pretty much any role-playing game. As much as I love to game, there are always those people out there with much more time on their hands. There is always someone to figure out which combination of race and class is the best, which branch is the best part of the skill tree to take, etc, etc. Inevitably, I’d be feeling like I made a mistake at some low level or even at the point of character creation that didn’t fully manifest itself until I got to a higher level and realized I’m just not as effective a character as I could be, but there’s no way to correct it without “re-rolling”.

In Aethora, you are not allowed to delete any characters; you can only change their name or appearance at any time. If you decide that one of the roles a PC is playing is not the ideal role for the balance of your party, you simply re-equip them and start them down the path that works for you. No regrets means no re-specing and no re-rolling.

2. Roleplaying for roleplaying’s sake, not as an excuse for convenience.

This principle is not so much a hard and fast rule, but more of a guiding ideal. I think, at the core, what this comes down to is honesty. If players are given some obviously convenient excuse for the blockage of a path or method, then they are going to lose trust in the game designer. Blatant abuse of “magic” explanation or other non-explanation of game mechanics weakens immersion, and when immersion breaks down, a player is going to start to see the “human side” of the developer. If you’ve ever played Pencil and Paper role-playing game, you may remember some moments when your Dungeon Master tried to railroad you down a path that they had meticulously laid out for you. Sometimes a player’s natural reaction to being railroaded, oddly enough, is to try to jump off the tracks. This is the kind of thing that reminds a player that they are playing a game with limitations; and that’s what I mean by “weakening immersion”.

Take the example of a 3D MMORPG. A lot of times, travel can be a real pain for players in a ginormous 3D world. To keep people from getting frustrated, developers might introduce ridable mounts that increase travel speed. This example makes perfect sense – the player doesn’t have to stretch any imagination to get on a horse and move a little faster. Now say, after a while, the developers decide that players aren’t getting to all the new fancy areas they’ve put in, so they want to make travel even more convenient; so they introduce a magical teleport system where any player can walk up to an area and be beamed over to another area fairly easily. While the new system is certainly more convenient for players, this is, in my opinion, an example of breaking the RPG setting and simply making it easier to get to the hack-n-slashing. When a player has to cross a long expanse of land to get to their destination, they develop an appreciation for the vastness of the world their character inhabits. When they bounce around via a loosely-expounded teleportation device, the world becomes a lot smaller.

3. Avoid imposing realism in favor of fun.

In some ways, this principle is the opposite of #2, but it takes a slightly different mentality. When designing an RPG system, it’s tempting to try to be as realistic as possible, whether it’s in combat, travel, basic survival, etc. One of the classic examples is the notion of hunger. In EverQuest, like many text-based MUDs before it, a player is required to carry food and drink with them at all times. In the old MUDs, you used to have to manually eat and drink food until you were satiated. In Everquest, they automated it slightly by making your character periodically eat something from their inventory. If the character had no food, they would start to get hungry (and eventually, once hungry enough, penalized in combat).

For a lot of players, this type of realism is part of the challenge of role-playing. For many others, however, it becomes just a big pain in the neck. It’s not really very mentally challenging, unless you consider trying to remember to buy food when in town a mental challenge. For me as a player, it became the most annoying when I regularly ran out of food while out adventuring and sometimes had to trek back to town just to fill up.

Whenever something like that happens, the player feels like they are doing work rather than playing. Sometimes, you have to do a little work in an RPG – that’s the nature of that style of game. As long as it’s balanced by fun, then a little work is okay – but too much work overshadows fun. That’s kind of a key point, so I’m going to restate it: If I feel like a game is making me do too much work, I’m not going to play it.

4. Heroes don’t have time for pest control jobs, I don’t care how inexperienced they are.

This principle might be specific to the setting, but honestly, I think it can be applied to most role-playing games out there. Ok, sure, the point of an RPG is that you start with small challenges and work up to larger challenges. But why, oh why, do I always have to start out killing rats? Don’t you think it would be a little more fun if we started our characters a little later in their careers? In D&D terms, I’m talking about starting at level 3 or so instead of level 1; when I first start out let me fight some orcs instead of garden snakes. I mean, come on – can you even imagine trying to stab a rat with a dagger? Wouldn’t it make more sense for that shopkeeper to just put down some rat traps or some rat poison?

So why does a typical RPG start you out on pest control duty? To be honest, I think designers like to make those first couple of levels ridiculously easy so (a) you’ll get used to playing the game and (b) you’ll get addicted fast. All of us RPG addicts are sucked in by accomplishments. We live for that “ding” sound, and once we’ve gone from level one to level two, we feel like we’ve made an investment.

The “pest control” concept goes beyond those initial stages of character development, though. For this reason, I’ve made it one of my principles. Whenever you ask a player to: clear an area of infestation/invasion/etc; bring back N number of pelts/sashes/ears; scavenger hunt for ores/oysters/Easter eggs; in any kind of typical mindless hunter/gatherer scenario, you’re basically giving the player busywork. You’re not challenging them with making appropriate decisions or problem solving – you’re acting like that doddering old substitute teacher who would come in and make the class do macaroni pictures or origami rather than attempt the lesson on fractions.

Again, why do we see this style of “quest” so often in RPGs? They make good time-sinks. Sometimes mindless play is actually pretty entertaining; heck, sometimes that’s exactly what we’re looking for in a video game. But personally, I feel like there are enough opportunities in any online RPG to go out and enjoy mindless combat. If I’m really on some kind of Quest or Mission, I want a little more of a challenge. To me, that’s what defines a Quest or Mission: it’s a challenge (and there’s a reward when it’s complete).

Continue reading principles 5 through 9 in Game Design Principles – Part 2.

I posted this on my other, more tech/web-dev oriented blog, but since it’s a great tool (or at least example to learn from) for web-based game developers, I figured I’d mention it here.

MoveableMap is a javascript library (open source, MIT license) that allows you to turn any block of HTML into a draggable, moveable entity within a viewport. Similar to the draggable behavior of Google Maps, but hopefully very easy to implement.

More information and demos can be found here: MoveableMap

Wow, it’s been a while since my last post. I wish I had time to do this more often, but such is life.

I’ve been thinking a lot about statistics lately, and how they can be used in game design. We’ve all seen this problem in any game, particularly indie games (including a lot of browser-based game) – a problem with randomness. Sometimes a game doesn’t appear to leave enough to chance, and it becomes predictable. Other times a game is too random, to the point of frustrating a player when despite skill or a “better hand”, fate can easily turn against them.

This article will be the first in a series of probably three articles on statistics and randomness. Today I’d like to talk about what it means to consider the odds that an event might happen, given multiple attempts at it. For example: if an event has a 25% chance of occurring, you might expect that given 4 attempts at it, you’re pretty much guaranteed success. Given a second thought, we know that not to be exactly true. So what are those odds, anyway? More after the jump.

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Browser-Based Game designers, take note from some of the web-based app designers: the term “Look and Feel” means more than you think! Win back some of those players you frightened away by seeing your game through their eyes and giving them some familiarity to start with.

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Today I learned a new acronym: PBBG. Persistent Browser-Based Game. Acronyms are great because they are these kind of self-importing entities that have the potential to carve something substantial into the world’s vocabulary. Just by the very act of instantiating a new acronym, you’ve taken the first step towards establishment, acceptance, and eventually, household knowledge.

Ok, maybe that’s a bit extreme, but one thing you can say about an acronym – the subject of an acronym is being talked about enough and with enough consistency to warrant abbreviation.

I’m here to embrace PBBG. I happen to be the sole developer of a PBBG (a label I applied just today, of course) called Pioneers of Aethora (more about that later). It’s actually an extreme convenience for this acronym to come along. I’ve been googling about, trying to find suitable testers for my game, and lemme tell ya – it’s hard to nail down what a PBBG is. You’ve got your web-based games, probably 99% of which are Flash-based and are most definitely not persistent (unless you count scoreboards). Then there’s “online RPGs”, which typically lands you in MMORPG-dreaming land. Or you can try “Indie games”, which will probably help you find some great sites and forums, but I’ve noticed that’s these places are usually looking at downloadable/installable games (they’re usually receptive to web-based games to some degree, but it’s not their focus). Lastly, trying to search on anything too generic with “rpg” in it drums up a whole lotta stuff about Pen and Paper RPGs (including independently produced P&P RPGs, which I would have found extremely cool at one time).

So what exactly is a PBBG? Well, there’s a definition at http://pbbg.com/ that’s pretty good. Essentially, we’re talking a game that you play in your browser; as in no installable/executable. But it’s not one of these puzzle/casual/action/arcade kinds of games where you play, get a score, try to beat your score, get addicted, try to beat everyone else’s score, etc. Instead, the game is persistent. Typically, this means it’s going to be a role-playing game of some kind. You create a character (or characters, or a kingdom, or a pet monster), you play a little, you go away, you come back tomorrow and pick up where you left off.

It’s the pretty standard concept behind an RPG, but I’m glad someone created this acronym to distinguish these browser-based RPGs from other web-based games, and as well from non-browser based “online/multiplayer” RPGs.

It’s not just the name, or the acronym, however, that makes me happy about this; it’s the fact that we’re witnessing a new gaming genre being established. Sure, it may be yet another spinoff or sub-genre of some pre-existing concepts, but the scaffolding for this PBBG genre has some very unique and exciting characteristics. The last couple years have been all about Web 2.0, and while it’s hard to distinguish hype from reality, there are aspects of Web 2.0 that lend themselves very nicely to web-based gaming.

Let’s consider some of the hurdles an independent game developer faces when constructing a game.

• UI development. Personally, I’ve started work on a few games myself that began as text-based, and when it came time to start adding a graphical interface, well… that just steepened my learning curve a bit, didn’t it? With a web-based game, you can do a hellavalotta presentation with HTML and CSS, and when you need to, javascript can fill in the cracks.
• Data retention. Serializing classes and writing them to files, reading them later, trying to keep them indexed, etc. I never got very far with that part either. With a PBBG, you’re most likely developing with a language that has built-in hooks into any database you could think of (not to mention memory caching options).
• Networking. I never got this far with any of my games. I had a lot of spectacular plans, lemme tell ya, but it wasn’t gonna happen. Obviously, not an issue in PBBGs – you get the networking for free.

There’s probably other stuff I’m not thinking of. All this PBBG talk makes me think there are others out there just like me – big aspirations for developing a game independently, but too many obstacles. Now I’ve got this game that’s downright playable. The progress of web technology has given us a new platform, a new sandbox to play in, where our unrealistic and perpetually unfinished projects can get closer to actuality. Just like the youtubers who suddenly discovered that they too could film a video and share it with thousands of people, we’re realizing that we can develop our own multiplayer, networked, persistent games.

And we don’t have to use C. Or C++. Or C#. Or (as Q-Bert would say) C#$%^&.

Have Kingdom of Loathing and Neopets paved the way for a gaming revolution? Or just another cool acronym? Here’s hoping it’s both.