Each stage's map is composed of six separate variable-length streams of data. They are:

• Curvature
• Height
• Lanes
• Right side objects
• Left side objects
• Hazards

Curvature controls the left-right turn of the road. It is stored as a sequence of bytes of the form $CT where $C is a count (1..15) and $T is a type. The valid types are:

• 0: Straight
• 1: Right
• 2: Right Hard
• 3: Right Very Hard
• 8: Straight (alternate)
• 9: Left
• 10: Left Hard
• 11: Left Very Hard
• Other values are unused by the game.

A zero byte in the stream is an escape which can be followed by one of:

• 0: Jump. The next two bytes are the address of the next byte in the stream.
• 1: Fork End. Used during road forks.
• 2: Split. Used to follow road forks. The next two bytes are the address of the left fork's data, and the next two bytes are the address of the right fork's data.
• Other values are invalid.

This escape format is the same for all the other streams.

Height controls the up-down inclination of the road. It uses the same encoding as curvature but the type field instead defines the road's inclination. Its valid values are:

• 1: Going Up 7 (steep incline)
• 3: Going Up 5
• 5: Going Up 3
• 7: Going Up 1 (gentle incline)
• 8: Level Road
• 9: Going Down 1 (gentle)
• 11: Going Down 3
• 13: Going Down 5
• 15: Going Down 7 (steep)
• Other values are unused by the game.

Lanes use a different scheme: pairs of bytes. The first byte is a count and the following byte is the data. The currently understood valid data values are:

• $00: [ |||| ] 4 Lanes
• $01: [ ||__ ] 2 Lanes, Left Aligned
• $02: [ _||_ ] 2 Lanes, Centre Aligned
• $03: [ __|| ] 2 Lanes, Right Aligned
• $06: [ /||_ ] 3 Lanes to 2 Narrowing, Left Aligned
• $0F: [ _/|| ] 3 Lanes to 2 Narrowing, Right Aligned
• $1F: [ _\|| ] 2 Lanes to 3 Widening, Left Aligned
• $2D: [ \||_ ] 2 Lanes to 3 Widening, Right Aligned
• $45: [ ____ ] Tunnel start
• $59: [ ____ ] Tunnel cont/end?
• $81: [ |||_ ] 3 Lanes, Left Aligned
• $82: [ _||| ] 3 Lanes, Right Aligned
• $8E: [ /||| ] 4 Lanes to 3 Narrowing, Right Aligned
• $9E: [ \||| ] 3 Lanes to 4 Widening, Right Aligned
• $AD: [ |||/ ] 3 Lanes to 4 Widening, Left Aligned
• $BD: [ |||\ ] 4 Lanes to 3 Narrowing, Left Aligned
• $C1: [ |||| ] 4 Lanes, Dirt track
• $C2: [ _||| ] 3 Lanes, Dirt track, Right Aligned
• $C3: [ __|| ] 2 Lanes, Dirt track, Right Aligned

Right and Left side objects are encoded in nibbles as for curvature data. The object types (for Stage 1) are:

• 0: Nothing
• 1: Tunnel Light
• 3: Short Pole
• 4: Tree
• 5: Bush
• 6: Street Lamp
• 7: Telegraph Pole
• 8: Turn Sign, Pointing Left
• 9: Turn Sign, Pointing Right

Hazards are encoded only as byte counters and an extended form of the escapes with the following additional codes:

• 3: (TBD) Stop Spawning Barriers
• 6: (TBD) Stop Spawning Barriers
• 7: Start Spawning Barriers Left
• 8: Start Spawning Barriers Right
• 9: Start Spawning Two Barriers
• 10: Set Floating Arrow Off
• 11: Set Floating Arrow to Left
• 12: Set Floating Arrow to Right
• 13: Enable Car Spawning
• 14: Disable Car Spawning