engine

atmospheric/environmental effects
- fire: campfires, lava, tiki torches
- incremental car damage: dents, hood/trunk open/flap, engine smoke, scrapes
- smoke: campfires, car (exhaust, tire skids)
- sparks: car impact/scrape, bombs
- spray: waterfall mist
- steam: lava
- tire skid marks: dirt, grass, mud, roads, (ice, snow)?
- tire kickup: dirt, grass, mud, water, (ice, snow)?
- water: drops (tunnels), falls (natural, dam), rapids
- weather: transitions (slightly foggy to clear), rain/snow?
- other
  - falling tree leaves
  - moving log conveyor belt
  - windshield collects rain drops & snow flakes?
environment mapping: cars (shadows)
lighting: lens flare (Xbox only?)
particle effects: falling leaves, fire, shooting lava, smoke, sparks, steam, tire kickup, water drops, waterfall mist
physics: slippery surfaces (dirt, grass, gravel, ice/snow?, water puddles), most pushable objects knockoverable
reflections: rearview mirror, puddles (-vehicles)
shadows: stencil buffer, tree/building shadows accurately cover vehicles when driving under them, player character shadow fades and completely disappears when car is covered fully by other shadows, rotates/scales relative to light source
texture: filtering (bi-, trilinear, anisotropic), mipmapping
transparency: glass, water

character

player character: cars
actions: gas/forward, break/reverse, shift gear up/down, turn left/right, look behind, handbrake, horn/siren, call for backup/helicopter (police mode)
tire rollover: asphalt, dirt, grass, metal grates, cobblestones, wood (bridges)
NPCs: vehicles (cars, helicopters)

# levels: 4 tracks (6 variations)
locations: Alpine (forests, mountains), beaches, Mediterranean (Greece), tropical (Hawaii, volcano)
interaction
- knock over/push: chairs, gas pumps (some), ladders, parking meters, road barrels, streetsigns, tables, other vehicles
- gas station sound