Hello everyone, my name is Mat Thomas and I am a game designer here at United Front Games working on ModNation Racers. Today I want to talk about our approach to the racing and give you an insight into the philosophy around developing the handling, weapons and AI.
When we started working on ModNation Racers we knew we couldn’t simply create a basic physics system to deliver our core race experience. We were also weary of the fact that unlike many racers, the player in ModNation Racers will also be focused on weapon play. Very early on in development we experimented with extremely tight handling (akin to driving on rails) and a much more physical race experience. What we soon realized is that when the handling model is tight, there is not much fun in the race experience, it was essentially too easy and likewise when the user is spending a lot of time concentrating on just keeping the vehicle on the track with a more complex handling model then this doesn’t leave any mental power to experiment and use weapons. So as you may expect we ended up with something in the middle which offered us the physicality and emergent feel that for us makes this feel like a true next generation karting title. What we found is that this made the handling very much pick up and play, and easy to understand but at the same time offering depth you’d expect in other racers.
The other key component to a kart racing title is the drift, and we focused very hard on this to make it fun. Our drift is simple to use; the player simply presses and holds the X button to engage the drift. The key thing is that while drifting the user can still steer, influencing the turn and the counter-drift. Holding the drift as long as you can and disengaging at the right time can become quite an art. This is made more fun by the endless number of track designs we expect from Track Studio. Successful drifts are rewarded in our other key component: the boost meter.
We decided very early on in development that in order to make sure the race experience is fun at all times, the player should have a lot of different abilities even when they were unarmed. All of these abilities are then tied back into our boost system – we encourage the user to earn boost by doing a variety of abilities. These include drafting, spinning, hopping, hitting enemies and of course drifting. The better the player is at this then the more boost they will accumulate. This accumulated boost can be spent in several ways: the player can obviously boost, but also the player can use their shield to defend against weapons, or spend boost on delivering a tough ramming attack on a nearby opponent in the form of a sideswipe. The result is that even without weapons the player can combine all these skills to have a great race experience.
In terms of weapons, no kart racing game can go without them! Again, we set out early to try and add depth to the weapons system. You can play ModNation Racers by collecting weapons and firing them but the key is what we have called the ladder system. In a nutshell, the more item pods you collect the better the weapon you will get. In all, we have four classes of weapons with three levels to each. Also you can convert all weapons to secondary weapons that can be dropped behind the player. The depth this adds is great; it gives the player the option to either save up weapons to get to the more devastating weapons or simply fire as you please. Saving up can be risky however, as the player will lose item pods if hit by other racers. This really helps build up different strategies, and we have found playing the game here at UFG that people approach the weapons in very different ways. Personally, I am big fan of constantly firing so I don’t tend to upgrade all the time but then again, I don’t win all the time!
Finally I will touch on the artificial intelligence (AI) and how we approached this. Fundamentally, approaching the AI has been a very complex process but the goal has been clear – the AI has to be competitive, the AI has to be fun to play against and it needs to feel fair. Also layer on top our biggest challenge: how do you develop AI when anyone can create a track that contains anything?
Traditional racing games rely on the fact that the tracks never change, and good racing lines can be recorded or generated during development. Since we did not have this luxury, our development team followed a river analogy for the AI. A river flows along its path, around any obstacles such as rocks, forming rapids through tight spaces, and slowing down in wide open areas. Similarly, we have created a flowfield that is interrupted by avoidable objects, and flows towards the apex of corners or special objects such as boostpads. The AI racers then “flow” along this “river”. Everything is computed in real time, which would not have been possible without the incredible power of the PS3’s cell processor.
The result is AI that feels very smart, can react to anything thrown at it, and can make key decisions at the right time. Give it a go in the public beta in Track Studio; build any track and go to test race to see how the AI deals with your designs!
Anyway, that is it for now. Stay tuned for future posts where we will go into more detail on the racing, and we look forward to hearing from you all.
