Scene elements (.scn)

The scene module (0x469000-0x471000, src/game/scene.c) reads the text files next to each track in GameData/Track/:

File	Read by	Holds
<track>_cameras.scn	Scene_LoadStarts 0x46cc00	replay/TV cameras and the camera-switch triggers (type 6)
<track>_audio.scn	Scene_LoadStarts	positional sounds
other <track>*.scn	Scene_LoadStarts	anything else whose name starts with the track's
<track>_FStart.scn / _BStart.scn	Scene_LoadStartScenes 0x46d550	the start (type 2) and end (type 1) lines and their banners, forward / reverse
<track>_ST<n>.scn	Scene_LoadSkillTest 0x46d280	a skill test's lines ("Start", "End") and cones

Track_LoadWorld (0x487650) loads them after the world: Scene_LoadStarts, then the skill test (game type 4, test number 0x657c80) or the start file of the race's direction (reverse flag 0x657430). Scene_LoadStarts lists <dir>*.scn, upper-cases each name and the track's, and parses every file that starts with the track's name unless it goes on with _FSTART, _BSTART or _ST. The Monaco tracks and the skid pad have no start files; the original builds its "Failed to load Start/End File" message and doesn't show it.

File format

Text, opened in text mode (CR LF reads as LF). Scene_ParseElements (0x46c170) reads a word with fscanf("%s") until the stream's end flag is set; a known keyword creates the element and calls its load (vtable slot 1), any other word is skipped. Each load reads its version with %d and then that version's fields with fscanf straight into the object, and most versions end with two fgets of the name field (the rest of the numbers' line, then the name line) whose last character (the newline) is cut. The port keeps every element as its object's byte image and reads with the exe's own format strings (src/game/scene_crt.c), so the runtime's behaviour carries over, notably: %d stores four bytes, so an int read into a 16-bit field spills its upper half into the next field until that one is read; whitespace in a format (a newline too) skips any amount of input whitespace.

Keyword	Class (vtable)	Size	Versions read	Versions in the data
AUDIO_ELEMENT	CAudioElem (0x5b4b58)	0xa4	1-4 (1 without a name)	4
GEOM_ELEMENT	CGeomElem (0x5b4280)	0xc4	1-5 (1 without a name)	4, 5
TRIGGER_ELEMENT	CTriggerElem (0x5b4554)	0xf0	1-5 (1 without a name)	3, 4, 5
CAMERA_ELEMENT	CCameraElem (0x5b4228)	0xc4	1-4	4
PARTICLE_ELEMENT	CParticleElem (0x5b44ac)	0x7c	1	none

Quirks kept: camera version 2 has no break and reads a whole version-3 element after its own; trigger version 2 jumps into version 4's tail (so it reads a name, version 1 doesn't); geometry version 4 reads an eighth number into a local that is dropped; the trigger constructor computes the line's end points from a field it hasn't set yet (every version then reads them, so the port leaves them zero).

Layouts

Common (CSceneElem, ctor 0x46bb30): +0x04 active byte, +0x08 position, +0x14 orientation (3x3, rows right / up / forward), +0x38 name (64). Slots 12-19 are the getters and setters of these (0x46bdd0 ... 0x46be40).

• Trigger: +0x7c type (0 ?, 1 end line, 2 start line, 6 camera switch, others events), +0x80, +0x84 (1.0), +0x88 width (3.0), +0x8c (0.25), +0x90, +0x94 (200), +0x9c, +0xa0, the line's end points +0xa4 / +0xb0, two direction vectors with flags (+0xe4 + +0xbc, +0xe8 + +0xc8), +0xd4 id, +0xd6, three links +0xd8 +0xdc +0xde (element indices; Scene_ParseElements adds the list's size before the file), +0xe0, +0xec.
• Camera: +0x78 (12), +0x7c (1), +0x80, +0x84, +0x88 (1), +0x8c (1), +0x90, +0x94 (3.0), +0x98, +0x9c field of view (37.5; the data has 45), +0xa0 (0.6), +0xb4 target, +0xc0 type (1 forward race, 2 reverse).
• Geometry: +0x78, +0x7c object type (four characters: FNSH, CONE, ...), +0x80, +0x84, +0x88, +0x8c, +0x90, +0x94 scale (percent, 3 floats), +0xa0 the orientation times the scale (0x46af60: Mat3_Mul(orientation, diag(scale) * 0.01)).
• Audio: +0x78 byte, +0x7c vector, +0x88..+0xa0 16-bit fields and two floats (+0x8c radius 100, +0x90), +0xa2 byte. The constructor also fills a table of circle points from the radius (0x4abf60, the editor's display; pending).
• Particle: +0x78 int (-1).

Lists

After a load the scene is one list (0x628168) and four built from it:

List	Built by	Getter
cameras (0x628178)	0x46ca50	Scene_CameraCount 0x46d8b0, Scene_Camera 0x46d8d0, Scene_FirstCamera 0x46d7e0
camera-switch triggers, type 6 (0x628174)	0x46ca50	0x46d7d0
event triggers, types other than 0, 1, 2, 6 (0x62816c)	0x46c5d0	0x46d7c0
start / end lines, types 0, 1, 2 (0x628170)	0x46c820	Scene_FindTriggerByType 0x46d1e0, Scene_FindTriggerById 0x46d230

Scene_CountGeom (0x46d910) counts the geometry elements: the world's scene bundle gets that many instance slots. Scene_PlaceGeometry (0x46d120) puts them into the bundle (type, position, scaled orientation); the bundle's calls (0x482af0, 0x482f70, 0x482fc0) are pending in the world module. Scene_Clear (0x46cf60) frees everything (the camera-switch list only together with the camera list).

Scene_StartLine (port addition) gives the start line's position and orientation, the type-2 trigger, which the race code will find the same way.