Trans-Am Racing ’68-’72 Detailed at E3

The new Trans-Am 1968-1972 sim from GT Interactive was on show at E3. Due for release Q2 1999 it will feature great cars from this era such as the Dan Gurney AAR Plymouth Barracuda and Sam Posey Dodge Challenger T/A along with a great selection of historic tracks. Cars will deform, bounce, flip, and swerve when they ram into other cars and barriers, providing realistic 3D collisions and a very aggressive environment that does sound similar to the hardcore example set by the upcoming Grand Prix Legends simulation by Papyrus.

Modes

The core of Trans Am Racing consists of Simulation and Relaxed Realism. Simulation mode provides a very deep simulation of the Trans Am racing experience. Users have complete control over the configuration of their car, including suspension set-up, gearing, tire selection, etc.

The Relaxed Realism mode is for users who want to just jump in the car and race. In RR mode, most car parameters are pre-configured, and the dynamics are more forgiving.

Vehicle Dynamics Expertise

EAI possesses a wealth of expertise in the accurate real-time simulation of vehicle dynamics. EAI’s expertise in this area has been leveraged to produce a cutting-edge, real-time racing simulation that features vehicles with physically-accurate behavior. Cars pitch and roll, and powerslide through corners. Too much gas and the tires break loose; too much brake and the wheels lock up, sending the car sliding through a corner. Crashes are completely 3D; cars can get one or more wheels off the ground, rollover, and complete fantastic “end-os.”

Damage Modeling

Trans Am Racing features spectacular, physically accurate crashes that are calculated on-the-fly, based on the vehicles (and/or other objects) involved; no two collisions are the same. Damage incurred by a car effects its performance. For example, impacts to a car’s front end may lead to impaired handling. A flat tire will result in lost traction and much higher rolling resistance. Visually, cars will deform as they incur damage; body panels will crush and crumple. Smoke and steam issue from under the hood when drivers abuse their engines.

Race course models and associated assets

Trans Am Racing will include a minimum of 12 race courses with associated assets. These assets consist of any additional elements required for a given course (e.g., texture maps, sound effects, etc.). Each course and set of assets will be combined into a single file that the main Trans Am Racing program will be able to read.

Suggested tracks include:
Mosport (Canada)
Bridgehampton (NY)
Bryar
Lime Rock (CT)
Mid-Ohio (OH)
Road America
Riverside (CA) Kent

Vehicle models and associated assets

Trans Am Racing features 25 completely texture-mapped vehicle models. These cars represent the most influential and important cars racing in the Trans Am series between 1968 and 1972. Each car is accurately modeled and texture-mapped. Furthermore, Trans Am Racing models each car’s specific driving characteristics accurately for heightened realism.

Some cars included are:
’70 Plymouth ‘Cuda
’70 Dodge Challenger
’69 Chevrolet Camaro
’68 Chevrolet Camaro
’67 Ford Mustang Coupe
’69 Ford Mustang
’70 Boss Mustang FastBack
’70 Firebird
’70 AMC Javelin
’72 AMC Javelin
’70 Chevrolet Camaro
’64 Pontiac Tempest GTO

Multiplayer Functionality

Trans Am Racing utilizes EAI’s multiplayer and online gaming technology to supports up to 16 players over a local area network and the Internet. Head-to-head play is supported via modem or serial cable.

Views and Cameras

Trans Am Racing features several in-race cameras (hood-ornament, cockpit, trailing near, and trailing far) and several post-race or replay cameras. During a race, drivers can toggle through the four available cameras and select one that best suits them. After a race, all or part of the race can be replayed from one of several cameras positioned around the track (e.g., corner cameras, overhead chase (blimp) camera, opponent cameras, TV cameras, etc.). Trans Am Racing also features a VCR-style interface for viewing race replays. Additionally, race and/or crash replays can be stored to disk for viewing later.

Automatic Anticipating Camera

Most contemporary racing games (e.g., simulation and arcade games) typically provide a locked down cockpit camera (i.e., perpetually pointed straight ahead). Real drivers don’t exhibit the same behavior; they’re always anticipating where their car is going to be. For example, when approaching a corner, drivers do not looking where the car is pointed;, they look at where they want to go, usually the apex of the corner. Trans Am Racing features a cockpit view with a camera that rotates to face oncoming track features, such as corners. This feature can be toggled by the users.

Computer-Controlled Vehicle Functionality (AI)

Trans Am Racing will also feature artificial intelligence (AI) that governs how computer-controlled vehicles navigate the courses. AI opponents are available during single-player and multiplayer games and emulates real drivers from the SCCA Trans-Am Racing Series. EAI has extensive experience implementing path-following algorithms.

Direct Model 3D Engine

Trans Am Racing’s Direct Model 3D engine builds three-dimensional scenes (e.g., race tracks, etc.) and displays them at interactive rates. The engine is flexible in that it is independent of rendering APIs. This independence allows EAI to select a rendering API based on the needs of the task at hand. Additionally, API independence allows EAI to quickly adapt to the rapidly changing 3D rendering API market. Trans Am Racing utilizes EAI’s Direct Model coupled to Microsoft’s Direct 3D API. This combination provides high performance 3D graphics on the broadest range of 3D accelerated hardware.

EAI’s Direct Model 3D engine employs a level of detail (LOD) management scheme that provides a number of methods for maximizing rendering performance, including automatic scene simplification, intelligent view frustum culling, spatial sorting, occlusion culling, and automatic texture map switching. The combination of these techniques allow EAI’s 3D engine to provide impressive performance while maintaining a high degree of realism.

Trans Am Racing supports as many as 16 cars on the track at one time. Additionally, as many as thirteen unique cars each with unique texture maps in a given race are supported. Full dynamics calculations are performed for every visible car up to approximately 16 cars. If it is necessary to display more than 16 cars on screen at one time, a “low-res” method for handling dynamics calculations will be used.

Texture capacity is maximized by using lit 8-bit palletized textures, sizing textures appropriate to the objects they are mapped to, optimizing model construction for more efficient texture usage, and texture map paging tied to our LOD manager. Smoke, dirt, and other similar effects will be handled as 3D particle systems composed of billboarded texture-mapped polygons (blended).

Vehicle Dynamics System

EAI’s Vehicle Dynamics system provides the life-like physics of vehicle movement, collision, and overall performance. The track details provide real-world effects, including road bumps, which cause the vehicle to pitch, roll, and bounce. The vehicle physics model expects driver inputs from steering, accelerating, and braking to create unique, real-time body movements. Inputs from both track and driver produce non-linear and sometimes unexpected results. Finally, variations in the road characteristics (e.g., asphalt, dirt, and grass) may provide variations in the handling of the vehicle.

Trans Am Racing’s realistic vehicle dynamics system is composed of three primary components; the suspension, tire, and powertrain models. Each component is optimized for computational efficiency. The suspension model is a sprung-mass model (seven degrees of freedom) with force inputs at each corner. The model accurately depicts the action and reaction of a car’s suspension as is navigates across three-dimensional terrain.

The tire model is a non-linear model that incorporates weight transfer, lateral velocity, rolling resistance and non-linear tire properties. The tire model is the most important part of the overall dynamics model; it will determine how the vehicle handles due to road inputs and driver demands.