Kicking the Tires of Forza Motorsport

Forza Motorsport™ is as much about style as it is about speed. The groundbreaking racing simulation from Microsoft Game Studios couples authentic car replicas with a new level of customization. The result is some of the hottest rides in town!

Lead Designer Dan Greenawalt let us kick the tires of some ofForza's custom cars, and gave us an insider's view of the game's outstanding graphics.

Xbox.com: Of the development time put in onForza, roughly what percentage of that work went to perfecting the accuracy of car models? What challenges did you encounter in creating so many authentic replicas?

Greenawalt: At its largest, the Forza Motorsport team was well over 100 people. We were in development for over two years. There's no good way to quantify this percentage. Let's just say, car accuracy was a significant investment and a labor of love.

Researching rare cars is always difficult. We put as many cars on the dynamometer (a machine that measures the torque output of a car—it's like a treadmill for a car) as we could. We wanted to get the audio and engine characteristics just right. We even put an Audi R8 on the dyno.

Xbox.com: How have you managed to maintain a high frame rate while simultaneously adding so many great-looking details? Was it a software solution? Was it original and/or unique methods devised by the Forza team?

Greenawalt: The Xbox® is a powerful platform and we've been working on it for a long time. Over the course of Project Gotham Racing®, PGR® 2, Midtown Madness® 3, RalliSport Challenge, and RSC 2, the individuals in our studio learned a lot of tricks.

Xbox.com: Which cars in particular are you especially proud of, and why?

Greenawalt: I'm constantly discovering new favorite cars in the game. Each car has its own "path to mastery." This means that each car drives differently and requires you to re-master the physics. My favorite right now is the old-style Viper ACR. It drifts well and it can chirp its tires into second and third gears (especially when upgraded).

I guess I'm most proud of the Panoz LMP Race Car. When I was down at Road Atlanta for the Popular Science test session, I had a chance to work with the actual pro race driver that tracks that car. Together, we tuned everything from downforce to brakes bias and dampers to be just right in the game. That was a ton of fun. It also means that that car is spot-on to the real world.

Xbox.com: The customizability options mean that no two gamers are likely to ever have identical cars of the same make and model. Could you describe some of the strangest, coolest, or most surprising custom designs you saw during development?

Greenawalt: What we did in development is nothing next to what players are doing, now that the game has released. We have over 100 creative people on our team. In the XboxLive™ community, there are hundreds of thousands.

So far, my favorite is the Mona Lisa. Someone used the 600 layers to recreate a remarkable Mona Lisa on their car. It's really quite amazing. Respect users by giving them powerful tools and then just sit back and watch. They never disappoint and always surprise.

Xbox.com: Do you foresee downloadable content for the paint-and-sticker customization fans? More shapes, etc.?

Greenawalt: We're still evaluating our downloadable content strategy.

Xbox.com: When and why was the decision made to include driver models? Did this particular component present any challenges?

Greenawalt: Look at PGR®, PGR 2,RSC and RSC 2. All of the racing games from MGS have driver models. Including an animated driver model is not new, it's expected.

Xbox.com: There appears to be a marked difference in look between the race view and replays. Do the replays get an extra graphical boost, and if so, how?

Greenawalt: Nope, no difference in the graphics and rendering. All games look more real with no HUD. There are two camera tricks we use to make the replays look more like TV. First, many of the cameras have a slight shake to simulate a hand-held camera. Second, several cameras use a variable focal length. This makes the action come into focus. We milked the Xbox for all it's worth during gameplay; there is nothing left to add for replays.

Xbox.com: You can really tear up the cars of Forza if you work at it. Was there any give and take on how to graphically represent car damage?

Greenawalt: Game development is all about give and take. Our goal was to simulate the type of damage you should expect on a race track while racing professionally. We did not worry about many of the extreme cases. We wanted to nail the feeling of rubbing and racing at your limits on a real-world race track in a real-world car.

Xbox.com: What do you think is the coolest way the team used graphics in the game? In your opinion, what one or two (or three or four) things look especially great in the game?

Greenawalt: I love the "jellyfish" look of the ghosts in Forza Motorsport. That was put in by one of the developers in his spare time.

The track surface looks great—individual skid marks that never repeat. It really roots the cars and gives drivers very good reference points around the track.

The dynamic gamma is pretty cool. When you come out of a dark tunnel into the sun, the scene adjusts the same way your eye does in the real world.

We've got some really long draw distances. On Blue Mountains, when you come out of the back section to the long straight, you can see for a half-mile. Most games can't do this.

The real-time reflections in the cars look really cool. I like to use the "lookback" camera to watch the reflection of bridges and other track objects pass over the headlight bezels of a car. Very cool-looking.

Xbox.com: Give me some jargon here if you can. What tools or tricks were used to get the perfect and realistic sheen of concrete in the sunlight?

Greenawalt: Specular Effect.

Xbox.com: The reflective surfaces of the cars?

Greenawalt: Cube Map.

Xbox.com: The lighting effects on nighttime courses?

Greenawalt: Radiosity and Light Map.

Xbox.com: The detailed landscapes surrounding each course?

Greenawalt: Track Environment.