论《At the Gates》与《文明5》的设计差异
当跟别人第一次谈起我的新游戏《At the Gates》（以下简称ATG）时，别人通常会问我，“你的新作与《文明5》相比如何？”在本文中，我将详细地回答这个问题！
这个决定的主要因素是，保证所有ATG的功能与它最重要的地图演化功能相结合。我的目标是以任何可能的方式实现这一功能。对于战斗，这是由供给系统完成的。缺少有效供给的单位会很快变得无用，这与《Unity of Command》类似。
Revisiting the Design of Civ 5
by Jon Shafer
Upon first telling people about my new game, At the Gates, I’m often asked, “How does it compare to Civ 5, the last title you designed?” Well, in this article I’ll be providing an in-depth response to that very question!
However, before really getting into the details (this is a long essay folks!) I’d like to step back and wax philosophical for a moment.
Civ 5 was a great success both critically and financially, and I’m especially proud of what the team accomplished. But there’s no ignoring the fact that Civ 5′s gameplay didn’t live up to everyone’s expectations.
I have no problem admitting that my design wasn’t perfect – we improve through constructive criticism and self-reflection, and that is another reason why I’m writing this. It wasn’t always easy, but I’ve answered many of the questions that at one time perplexed me.
Below, I’ll be sharing the design lessons I learned during and after Civ 5′s development, along with explaining how I’m actually applying said lessons in ATG.
Alright then, it’s about time we got this show on the road!
Out of all aspects of Civ 5 that I was involved with, I’m particularly proud of what our team accomplished with the UI.
Picking up a new strategy game is always tough, and a key factor in shaping that learning curve is how much help the interface provides (or doesn’t). We did a great job of focusing the player’s attention on what really matters. The size of each interface element reflects its relative importance, e.g. the end turn button is bigger than the button which shows toggleable map options. Rarely-used actions like disbanding a unit were tucked away into sub-screens. I have very much carried this philosophy forward into ATG.
My one disappointment with the UI was the general lack of “power features” tailored for hardcore fans. Ultimately, we didn’t end up with as many information overlays, screens or modes as I would have liked. One of my early goals was to have an alternate “expert” switch that you could flip, adding a significant quantity of detailed information to the screens and mouseovers. User-created mods have added this feature to both Civ 4 and Civ 5, but integrating it into the full games is obviously preferable.
This functionality is already supported in the structure of the ATG interface system, and it won’t be much work to flesh it out in full. I’m looking forward to seeing the community’s reaction to the finished version, and improving it even further during the alpha and beta testing process!
My experience with developing Civ 5′s diplomacy system has had the strongest influence on my present-day game design philosophy; the next most significant isn’t even in the same ballpark.
My original goal was for the AI leaders to act human. But humans are ambiguous, moody and sometimes just plain crazy. This can be interesting when you’re dealing with actual, real humans, but I learned the important lesson that when you’re simulating one with a computer there’s no way to make this fun. Any attempt to do so just turns into random, unproductive noise.
I came to realize that while diplomacy is a unique challenge, it’s ultimately still just a gameplay system just like any other. Regardless of whether your enjoyment is derived from roleplaying or simply a game’s core mechanics, if your opponents’ goals and behavior aren’t clear then you’ll have absolutely no idea what’s going on or what to do.
In Civ 5, you might have been lifelong allies with a leader, but once you enter the late-game he has no qualms backstabbing you in order to win. With this being the case, what’s the point of investing in relationships at all?
By no means should AI leaders be completely predictable. However, they do need a clear rhyme and reason behind their actions. The computer opponents in Civ 5 were completely enslaved to their gameplay situation, and as a result they appeared random and very little of their personalities shone through.
They were all crazy, and in the exact same way. In the months after the game was released I modified their behavior to be more predictable, but it was too late to completely change course. The biggest takeaway from this is that the only thing which matters in a game is the experience inside the player’s head. It doesn’t matter what your intentions are or what’s going on under the hood if the end result just isn’t fun.
Like other 4X games, diplomacy in ATG is built around your “relations” metric with other leaders. But compared with Civ 5, what goes into that number and what it does is very clear. For example, if you’re at -5 with a leader, he’ll never trade with you, while at +10 he’ll always agree to help out in a war if requested. Rather than trying to decipher what the RNG (random number generator)-based AI is “thinking,” your objective is instead to find as many ways as you can (afford) to boost that Relations number. Once you’ve done so, a variety of options for how your new friend can assist you become available.
Diplomacy is more than just fiddling with numbers though. There is still some randomness in the system, but not nearly as much as in Civ 5. Leaders in ATG have very distinctive agendas and behaviors: Attila the Hun is honorable, but vicious. Athanaric of the Goths is a religious fanatic. Drest of the Picts is kind of crazy, and you know you can’t trust him.
Out of everything related to diplomacy, leader requests are probably ATG’s ”sexiest” bullet point. In many other 4X games the road to friendship often involves little more than giving someone a big pile of money or technologies.
In ATG building up relations is primarily done by completing requests for leaders when specific crises afflict them. Coming to Attila’s aid in a war or giving him food when his people are starving in the middle of winter will earn you major, major points. Sure, giving him a fat stack of cash certainly won’t hurt, but building true friendships isn’t quite that easy!
Our goal with ATG is to produce the best diplomacy system. Ever. It certainly won’t be easy, but with what I’ve learned, a strong combination of character personalities and solid mechanics I believe that this is a goal very much within our reach.
The AI in the base version of Civ 5 was… not as strong as it could be, shall we say.
Working on this system was another experience that taught me a great deal about design and development. I wrote the AI code that handled the computer opponents’ high-level strategic goals, economy and diplomacy.
Like most engineers, I really enjoy architecting elegant and flexible structures. Civ 5′s AI was a beautiful mesh of interwoven systems, and even included the ability to record virtually everything to a massive log file. Unfortunately, my enjoyment of building caused me to fall in love with the design rather than its actual impact. I was very proud of my code. But it really wasn’t very good.
What many people don’t know about AI programming is that one of the greatest challenges is getting your artificial players to actually do what you think you’re making them do! The AI code in a big strategy game is typically so complex that you end up with a variety of pieces that either don’t function as expected, or worse, don’t do anything.
Another problem with my AI was the randomness, which is something I’ve already talked about at length. The computer opponents were weighted towards a variety of possibilities, with a healthy serving of RNG (random number generator) on the side. This meant they floated from one “strategy” to another without any real cohesion behind those decisions. This approach is nice in theory, but if you want a strong AI there are times when you need to force it to behave in very specific manner.
What all of this adds up to is that with ATG I’m staying completely focused on the end goal: results. This means a much simpler AI system, which in turn will result in a much stronger opponent.
When you as the developer know exactly what an AI player is doing and why, it becomes much easier to recognize bad behavior and fix it. And the fewer moving parts you have the easier it is to tell what’s going on.
Along with my new approach with AI design, Jonathan, our architect, is a programming wizard and has several ideas for how we can make this code super efficient. This will allow us to use far more processing power than we could otherwise, while keeping end turn lengths short to boot. I’m by no means the most skilled programmer in the world, but with the two of us together I have confidence the AI in ATG will offer players a very real challenge.
One of the big changes I made to Civ 5 on the economic front was the shift from resources being “boolean” (where you either have them or you don’t) to “quantified,” where you can have zero of a single resource type, or two of it, or maybe eighteen. I still feel that making them quantified was a solid design decision, but for a variety of reasons the execution wasn’t everything I wanted it to be.
Civ 5 featured a ”popcap” resource model where eight Iron basically provides eight “slots” that you can use to build (you guessed it) eight Swordsmen, or Catapults or whatever. ATG will instead feature a more traditional “stockpile” resource model where quantities build up over time and are then spent all at once in chunks. This requires more micromanagement than the popcap model, which was one of the reasons why I steered clear of it in Civ 5. In ATG, though, the focus is on the strategic level (empire-wide resource management) instead of the tactical level (city and population management), making this a much better fit.
In Civ 5, players ended up with easy access to a bit of every resource and there was almost no reason to trade. In the real world, swapping goods is worthwhile because of the effects of supply and demand. In Civ 5 there was almost no demand since you could be virtually self-sufficient. This will be completely different in ATG, where the threat of critical shortages will always be right around the corner, and bringing in much-needed resources via trade might very well be necessary for survival.
My removal of the health system in Civ 5 also had repercussions elsewhere. This greatly reduced the value of non-strategic resources (like wheat), and in retrospect it’s clear that I didn’t manage to fill that void with something else. ATG has far fewer resource types than Civ 5, but the ones which do exist are all very important. The map is absolutely vital in a 4X game, and that needs to be the case for everything on it as well. If you see something on a tile and think it’s not a big deal, that is a flaw that needs to be fixed.
Another issue with the Civ 5 resources system was that the difference between having 2 and 5 Swordsmen isn’t really a big deal when compared with the possibility of not havingany Swordsmen. If I were able to go back and change the design I probably would have resources show up in more limited quantities and make the units and buildings they unlock much more unique and powerful.
Most armies would be composed of ”lower tier” of units like spearmen, with the occasional swordsman or catapult spicing up the battlefield by serving as targets or threats to avoid. It would require some work to balance and players would all need roughly equal access to resources of some kind, but I very much believe this type of approach could work.
I made a number of tweaks to the traditional Civ economic system with v5, and as with the resources the results were a mixed bag.
My intention with the global happiness mechanic was to make it possible for smaller empires to compete with much larger ones. The problem was that a global metric butts heads with the natural cadence of the entire genre. I mean, the second X in 4X stands for “expansion” for crying out loud! I lost sight of this as I pursued other objectives.
The problem was that happiness strongly encouraged you to stay small and the penalties for not obliging with this demand were quite harsh. It was virtually impossible to build the large, sprawling empires which had always been a feature in the series and served as the entire point playing for many people. I still believe that there are ways to make smaller empires viable, but it shouldn’t come at the expense of those who enjoy expanding. Penalties should be challenges to overcome, not an insurmountable wall to be frustrated by.
Carrying forward lessons from my experience with global happiness, ATG is much more freeform when it comes to expansion. There are factors in the game which discourage mindless spamming of settlements, but none of them are as heavy-handed as exponential maintenance, corruption or empire-wide unhappiness.
For one, the world of ATG is much more dangerous than that of Civ 5. Everyone is hungry and searching for cheap and easy snacks. Balancing economics and defense is absolutely crucial, and intentionally a tricky tightrope to walk. Additionally, the economic value provided by settlements is not particularly significant, as most resources can only be produced by improvements.
Further, each individual settlement you control eats into your food supply above and beyond what the population consumes. Food is extremely important, and wasting it extremely foolish. You can certainly build a massive empire in ATG if you so choose, but always make sure you can feed and protect it!
My removal of the research/commerce/culture sliders also came with positives and negatives. I’ve always found fiddling with sliders in strategy games to be boring busywork, and in that sense I don’t miss them. But the sliders also had a hidden value that I didn’t realize until later – they gave players the ability to shift directions at any time.
I’ve written at length about the importance of adaptation in strategy games. Unfortunately, once the sliders were gone players were basically permanently locked into their past economic choices.
There was no way to sacrifice research in order to upgrade your army, for example. Rewarding long-term planning is certainly a worthy endeavor, but you still need to provide tools to allow players to change course when necessary.
I like both the Policies system featured in Civ 5 and the Civics system from Civ 4, which are simply two different takes on the same concept: the ability to shape the “character” of your empire.
With Policies, I wanted it to feel like you were slowly accumulating this identity over time. After all, Japan and Germany changed significantly after World War 2, but they’re still Japanese and German, and maintain that legacy of honor, hard work, etc.
By contrast, Civics allowed you to completely reforge your empire on a dime. Sure, there were costs associated with doing so, but it was very much possible to transform from a pious peace-loving people into the warmonger scourge from hell. This is kind of odd, but it has a huge gameplay benefit.
Both systems have their strengths and weaknesses, but I now find the design of Civics more appealing, because of that capacity to make sudden and dramatic shifts.
In ATG we’ve basically rolled the tech tree and government systems into a single Romanization Perks system. A new Perk can be chosen for each Roman city you capture and Roman diplomatic request you complete. As with Civics, you can later re-allocate your choices, although doing so temporarily lowers the stability of your empire (which reduces taxation, troop morale, etc.).
Along with my belief that adaptation is good just on principle, there’s another reason why I took more of a Civics-esque approach with ATG. The game is hard. The seasons are usually working against you. Resources are running out. Your neighbors are constantly eyeing up your improvements. The Romans are significantly stronger than you much of the time.
Players need tools to overcome these challenges, and one of those will be the ability to switch Romanization Perks at any time. This allows you slide into a completely different strategy to deal with whatever hostile and ever-changing circumstances you’re currently facing.
Not only is there a good gameplay reason to make it possible to easily change Romanization perks, but there’s also a historical one. During late antiquity the identity of the barbarian tribes evolved dramatically over short periods of time. After all, you don’t see Goths walking around these days! … Okay, come on guys, you know what I meant!
By far the most significant change I made with Civ 5 was to way in which wars were fought. Instead of large stacks of units crashing into one another as had always been the case in the previous Civ games, there was now 1UPT (one unit per tile). This forced players to spread out their armies across the landscape, instead of piling everything into a single tile.
This was a model very much inspired by the old wargame Panzer General. On the whole, I would say that the combat mechanics are indeed better in Civ 5 than in any other entry in the series. But as is the theme of this article, there’s a downside to consider as well.
One of the biggest challenges unearthed by 1UPT was writing a competent combat AI. I wasn’t the one who developed this particular AI subsystem, and the member of the team who was tasked with this did a great job of making lemonade out of the design lemons I’d given him. Needless to say, programming an AI which can effectively maneuver dozens of units around in extremely tactically-confined spaces is incredibly difficult.
The reason why this wasn’t an issue in Panzer General was that their AI didn’t actually need to do anything. It was always on the defensive, and a large part of that game was simply solving the “puzzle” of how to best crack open enemy strongholds. It was plenty sufficient if your opponents simply ordered a single tank to stir up some trouble every so often.
What made Panzer General fun was you blitzkrieg-ing through Europe while your enemies quickly and dramatically fell before your might. However, in a Civ game, the AI has to be capable of launching full-scale invasions, sometimes on different landmasses. Needless to say, we’re talking about a challenge on completely different scale.
Speaking of scale, another significant issue with 1UPT was that the maps wasn’t really suited for it. The joy of Panzer General was pulling off clever maneuvers and secretly encircling your helpless enemies. Unfortunately, in Civ 5 nasty bottlenecks aren’t uncommon and this tempers much of the natural value added by 1UPT. Ultimately, there just wasn’t enough room to do the fun part.
To address this, I could have done something crazy like added sub-tiles to the existing grid. I really don’t think this would have been a good idea though, as the whole point in having a tiles is that everything happens on the same playing field, which makes it very easy to tell what’s going on. Once you start muddying the waters of what goes where, you lose that clarity and mechanical chunkiness tiles offer. And at that point, you might as well just get rid of them entirely.
Speculation aside, the reality was that the congestion caused by 1UPT also impacted other parts of the game. In every prior Civ title it was no problem to have ten, fifty or even a thousand units under your control. Sure, larger numbers meant more to manage, but hotkeys and UI conveniences could alleviate much of the problem. But in Civ 5, every unit needed its own tile, and that meant the map filled up pretty quickly.
To address this, I slowed the rate of production, which in turn led to more waiting around for buckets to fill up. For pacing reasons, in the early game I might have wanted players to be training new units every 4 turns. But this was impossible, because the map would have then become covered in Warriors by the end of the classical era. And once the map fills up too much, even warfare stops being fun.
So is there a way to make 1UPT really work in a Civ game? Perhaps. The key is the map. Is there enough of room to stash units freely and slide them around each other? If so, then yes, you can do it. For this to be possible, I’d think you would have to increase the maximum map size by at least four times. You’d probably also want to alter the map generation logic to make bottlenecks larger and less common. Of course, making the world that much bigger would introduce a whole new set of challenges!
In fact, there were technical reasons this wasn’t really feasible – our engine was already pushing up against the capabilities of modern computer hardware. Drawing that many small doo-dads on a screen is really expensive, trust me. Well, unless you make your game 2D, like ATG!
Speaking of which, what about combat in ATG? Well, for one thing the game will allow for stacks of units!
The main reason for this is one of my high-level goals for the game. As I touched upon earlier, ATG is designed to be a strategy title which takes place primarily at the strategic level, rather than the tactical. The region of the map where you’ve stationed your armies, how well you’ve prepared your supply network, etc. is ultimately more important than if you were able to wheel one of your infantry around the flank of another enemy infantry unit.
A major factor in this decision was ensuring all of ATG’s features integrate with its most important one: map evolution. My objective is really to play this up in every way possible. With combat, this is done through the supply system. Units which lack sufficient supply rapidly become useless, similar to Unity of Command.
Every tile has a certain amount of supply available for units stationed there. The largest fraction of this comes from the tile’s terrain type which, of course, changes radically with the seasons.
The remaining fraction comes from the effect of nearby supply camps and settlements.
And supply is what the entire military side of the game is geared around – Planning ahead to make sure you have enough of it. Fighting in areas which have a lot of it. Ensuring that your supply nodes are safe, and so on.
In fact, the units themselves are almost a secondary concern. ATG is not a game where you follow the epic tale of a single warrior as he levels up and upgrades through the various technological eras. Instead, it’s more like a late-game chess match, when nearly any move can settle the battle, and a pawn in the right situation can be just as powerful as a queen.
No doubt, this is a very different approach from the one taken in Civ 5. However, by now it should be obvious that ATG is in no way Civ 5, but instead stands on its own as a unique and innovative new member of the 4X family!
The Civ 5 team was one of the best I’ve ever had the honor of being a part of. That group put a ton of love and great work into the game, and it really shows in the art, audio and tech.
Civ 5′s gameplay had several rough edges at release, but those were all due to decisions I made with the design. My friends over at Firaxis have done an excellent job improving the gameplay following my departure, and I can’t wait to see what they do next!
As I promised in the intro, I’m not shy about my flaws. The fact is there’s still much I have to learn. But every project is a new opportunity to improve and show everyone what you’ve learned. I’m very excited about ATG not only for this reason, but also because it’s a great chance to spice up the 4X genre and help point it in a interesting new direction.
I’m sure I’ll make more mistakes along the way, but I’m wiser than I used to be and can now the see problems from much further away. I ask that you join me on my journey, help contribute to At the Gates, and discover together the amazing places we’ll end up!(source:gamasutra)