NFS3/HS Tracks Overview

This help page describes the basic concepts involved in the structure of a NFS3/HS track. For technical information on the NFS3/HS file formats, please refer to the pages on NFS3 Track File Formats and NFSHS Track File Formats.

Track structure

NFS3/HS tracks are subdivided into track blocks (ca. 200-300 of them), each of which consists of track vertices, polygons, objects and virtual road data. The corresponding data are mostly stored in a file with extension .FRD, and for NFS3, with a companion file with .COL extension.

Vertices

These are the points which make up the track. They can belong either to the main track structure, or to a "polygon/extra/global object" (see below).

Polygons

A track block consists of three series of polygons, corresponding to various resolutions (the low and medium resolutions are only used to save computing time when the car is still far away). To every polygon corresponds a texture, and the high-resolution series of polygons is also associated with virtual road information.

Objects

There are several types of objects:

• Polygon objects (displayed in blue in T3ED) make use of the same list of vertices as the main track structure. Polygon objects are fixed and cannot be collided with.
• Extra objects (displayed in green in T3ED) have separate vertex information structures compared to polygon objects, extra objects feature collision detection and can be animated as well.
• Global objects (displayed in teal in T3ED) are similar to extra objects, but they are not bound to a single track block and can be seen from any track block. In NFSHS they can also be used a track props with mass and a hitbox (what is dubbed as "complex behavior")
• Light and sound sources: objects used to place light glows and ambient sounds, respectively.

Virtual Road

The virtual road is all the information used by NFS3/HS in order to compute the behavior of the various cars (player, police, opponents or traffic). This includes, in particular, a sequence of "virtual nodes" stored either in the associated .COL file (for NFS3) or in the .FRD itself (for NFSHS); virtual forward and normal vectors associated to every high resolution track polygon; etc...

Textures

The track textures are stored in a companion file with .QFS extension.

• For NFS3: four files are provided for each track: the files whose names end with a ‘0’ correspond to normal racing, while those which contain a ‘1’ correspond to mirrored tracks. The files with a ‘_8’ suffix in their name correspond to 256-color textures, while the others correspond to 65536-color textures.
• For NFSHS: there are either one (tr0.qfs) or two (tr0.qfs and trn0.qfs) texture files. tr0 is the texture file for the daytime track while trn0 is the texture file for the nighttime track.