After our profile and interview with Firemint about their upcoming Real Racing game, we opened the forum up to followup questions from readers.
Firemint provided detailed answers in two separate posts: one and two. We've included some of the highlights below:
Q: Seems like this is going for the "sim" racing experience (which has been missing from app store thus far). As such i feel the physics engine will need to be great to achieve that. … What sort of effects are included in the physics model? Will things like tyre grip, aerodynamics, centrifugal affects, downforce, drag, fuel – weight etc be modeled accurately?
Firemint: I am continually surprised by the depth of knowledge on these forums. All the things you mentioned are included in our model except for fuel and its effect on changing the weight. Having said that, our aerodynamic modelling is pretty simplified.
One critical component of the car model is suspension and the way that the weight of the car shifts to different tyre patches and affects steering, braking and acceleration forces. When it comes to car simulation, weight shifting and the rubber on the road is 90% of the problem. Centrifugal effects arise naturally from the rigid body physics model. Aerodynamics, engine and drive train simulation are all important but can be simulated to 90% accuracy with extremely simple approximations (so that is how we simulated them, simply). They tend not to make or break the fun factor.
After including all of these things, we have had to manipulate the model to ensure that it is, above all, heaps of fun. We are aiming for the handling to feel fun and realistic and you have to make some compromises on realism to achieve this. However we aren't just tearing up the rule book like a street racing game. In that sense, we still say that we are a sim.
One example of a little cheat that maybe I shouldn't admit to: all the cars are modelled like a rear wheel drive. This is fine for the muscle cars, but probably not so realistic for hatchbacks which should be front wheel drive. However, we think rear wheel drive behaviour is more fun than front wheel drive!
Q. Will other AI cars make mistakes or try and take you out?
Yes, they are actually quite mean at the moment, but you can be equally mean back. We have tried to make the AI a little more like how people play. Instead of getting everything perfect, they will sometimes slide out themselves and get in trouble. There are moments in the videos where you can see this. We're still refining the AI and with further focus testing we may still change our approach on this.
Q. Can we play music from iPod, with sound effects?
Firemint: Yes.
Q. Are the cars and tracks unique or based on real life versions?
Firemint: They are unique. We had a lot of discussions surrounding licensing early on, and it wasn't an easy decision not to go for it. The decision to avoid licensing was to maintain the fullest creative control. Once we made this decision, we actually felt quite liberated. We are now able to focus on a very pure sort of design.
Q. Is their online muliplayer like in Raging Thunder. Or even just local WiFi multiplayer? I'm talkin' trading paint, not comparing times…
Firemint: We’ll be able to answer these questions closer to release!
Q. Is there car damage?
Firemint: No. We like the idea but there are tradeoffs involved. We haven't ruled out car damage as a future direction for Real Racing.
Q: In previous videos we saw awesome graphics. Although they still look good, what happened? They look downgraded…
Firemint: It’s hard to answer this, because the game on device is looking better than ever. Screenshots and videos are something different from the actual game. Some of those screenshots look very unflattering compared to the real thing. The videos are probably more representative than screenshots but they suffer from their own problems.
There have been occasional mentions of frame rate problems in the video. This kind of makes me cry, because the problem is with the HD video playback in Flash and often Firefox, not the game. My computer cannot play back HD video from YouTube at more than 10 or 15 fps, and sometimes it is really choppy. Most computers can play it back fine, I think it is related to Firefox and Flash 9. This is not about Internet bandwidth, it is about the video playback engine itself. I can tell you that the game is running smoother than the video, even when the video is playing back as intended.
Also, while speaking of frame rate, our 1080i video camera cannot effectively capture at more than 25 fps because of the interlacing. The game however gets fps of up to 40. The more technical people here will understand the potential aliasing issues this introduces in the video.
Another example of unflattering shots is when you capture dynamic reflective lighting in a screenshot. A screenshot captures only one moment in time, but it is the movement of light over a surface that impresses.
There are other issues too, like color balance etc. Long and short of it: We don't have the online tools to demonstrate to you how smoothly the game runs and how beautiful the graphics and effects are on device. Like a photographer, sometimes you can capture what you are seeing and experiencing, sometimes you can't.
There is so much to talk about on this subject that maybe I should blog about it sometime. We have gone to lengths to provide raw assets, whether we consider them representative or not. So we are frustrated to see some games provide off-device screenshots and say "don't worry it is 'representative'". We are giving you raw stuff, as high def as we can get it, because we don’t want to use those tricks.
Q: Bonus question: A few people have commented on the apparent difficulty of staying on the track.
Firemint: …we got a bit carried away by the cool offroad effects and included too many of those in the video. The cars aren't on rails so while it's possible to go off road, a decent driver won't have any problems staying on.
To read the other answers, please visit the original discussion thread, and our original interview article which includes a high definition video of the game.
Firemint's Real Racing will become available in the App Store in April.
Last month, we previewed an upcoming iPhone game from True Axis called Jet Car Stunts. 
Luke Ryan: The True Axis Physics SDK was a bit of an accidental development. It started back in 2002 as part of a game demo I was developing. The physics engines back then were not good enough, and I already had a few years experience involving lots of physics programming, so I made a much better one. I started getting a few requests to make it commercial. In-between doing contract work for mobile and handheld games, I did all the extra work necessary to commercialise it, which was the reason for the formation of the company, True Axis.
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