Hi Octane

Levels?	Not editable
Tiles?	Not editable
Sprites?	Not editable
Fullscreen?	Not editable
Sound?	Not editable
Music?	Not editable
Text?	Not editable
Story/cutscenes?	Not editable
UI/menus?	Not editable
Demos?	Unknown

This article is partially complete. This means that all known information is here, but there is still more information that needs to be discovered and/or reverse engineered. If you know some of the missing information, you can help the ModdingWiki by adding this info yourself.

Hi Octane is hover-car racing game. According to Sean Cooper it was made in 6.5 weeks using engine code from Syndicate and Magic Carpet.

Tools

Level inspector and incomplete editor by movAX13h (contains all assets of the original game extracted/converted by srtuss): https://github.com/movAX13h/HiOctaneTools

File formats

The following file formats are used by this game.

Filename	Format	Details
`sounds/music.dat`	see below	Archive containing music files in different formats: XMI Format, GEN Format, ROL Format, WTB Format. There are five files per format : TGAME1, TGAME2, TGAME3, TGAME4, TINTRO2.

MUSIC.DAT

read the INT32LE at EOF and seek to returned position
count the N number of INT16LE that equals 0x0001, then read N of the following struct:

Data type	Name	Description
INT32LE	offTunes	Offset to the list of tunes
INT32LE	offTune1	Offset to the first tune
INT32LE	unknown	Unknown (always `0xC0000000`, or `192`)
INT32LE	lenTunes	Length of all tunes together, bytes

for each of the former struct
- seek to offTunes
- read one of the following struct, its lenTune indicates the byte sum of tunes following
- read as many of the following struct until their lenTune sum equals the one in previous step

Data type	Name	Description
CHAR	name[12]	File name of the tune, `\0` padded
CHAR	padding[6]	Padding bytes
INT32LE	offTune	Tune relative offset
CHAR	padding[4]	Padding bytes
INT32LE	lenTune	Tune length, bytes
INT16LE	unknown	Unknown (always `0x5A00`, or `90`)

you now have a catalog of a collection of tunes, e.g. five ROL songs, five WTB songs etc
to extract a song, copy lenTune bytes starting at offTune1 + offTune, file name is name

RNC-compressed files

Many of the game's files are compressed using the Rob Northern Compression format; some of them such as SOUND\SOUND.DAT are a concatenation of many RNC archives simply glued together.

A command-line unpacker can be found here : Bullfrog games RNC Utilities (from Unpacking RNC files)

DAT/TAB pairs

Can be decompressed using Bullfrog games DAT/TAB Graphics extractor (they first must be decompressed if they are RNC-compressed).

DAT format:

Without a TAB file, it's raw pixels; with a TAB file it's a form of line by line RLE compression where only transparent pixels are compressed.

TAB format:

Data type	Name	Description
INT32LE	position	Image position in .DAT
INT16LE	width	Image width
INT16LE	height	Image height

TMAPS:

Contains powerups and some HUD elements but TAB format is different:

Data type	Name	Description
INT32LE	flat	Size of RNC stream unpacked, useless as it's contained in stream header already
INT32LE	pos	Position in DAT
INT16LE	index	Some index but can be duplicate, so likely a type or category instead

There are N+1 entries to be able to compute last item size in DAT.

Each image has the following format:

Data type	Name	Description
INT16	unknown	Unknown
INT8	width	Image width
INT8	height	Image height
INT8[]	pixels	Image pixels, 8-bit paletted

Game's files

Name	Format	RNC compressed	Notes
data\hfont0-0.dat data\hfont0-0.tab	Unknown format	Yes	Thin white font (SVGA)
data\hspr0-0.dat data\hspr0-0.tab	Unknown format	Yes	Editor icons (large)
data\intro.dat	Autodesk FLI animation	No	Game introduction
data\logo0-0.dat data\logo0-0.tab	Unknown format	Yes	Game logo (VGA)
data\logo0-1.dat data\logo0-1.tab	Unknown format	Yes	Game logo (SVGA)
data\mfont0-0.dat data\mfont0-0.tab	Unknown format	Yes	Thin white font (VGA)
data\mspr0-0.dat data\mspr0-0.tab	Unknown format	Yes	Editor icons (small)
data\olfnt0-0.dat data\olfnt0-0.tab	Unknown format	Yes	Large white font (VGA)
data\olfnt0-1.dat data\olfnt0-1.tab	Unknown format	Yes	Large white font (SVGA)
data\onet0-.dat data\oscr0-.dat	Raw VGA image, 320×200 and 640×480	Yes	Loading and selection screens
data\osfnt0-0.dat data\osfnt0-0.tab	Unknown format	Yes	Small white font (VGA)
data\osfnt0-1.dat data\osfnt0-1.tab	Unknown format	Yes	Small white font (VGA)
data\palet0-0.dat	VGA Palette	No	The palette of every asset of the game, unless specified
data\panel0-0.dat data\panel0-0.tab	Unknown format	No	HUD 2-players (SVGA)
data\panel0-1.dat data\panel0-1.tab	Unknown format	No	HUD 1-player (SVGA)
data\panel9-0.dat data\panel9-0.tab	Unknown format	No	HUD 2-players (VGA)
data\panel9-1.dat data\panel9-1.tab	Unknown format	No	HUD 1-player (VGA)
data\pfont0-0.dat data\pfont0-0.tab	Unknown format	No	Large green font (VGA)
data\pfont0-1.dat data\pfont0-1.tab	Unknown format	No	Large green font (SVGA)
data\point0-0.dat data\point0-0.tab	Unknown format	Yes	Editor cursors
data\puzzle.dat	Raw VGA image, 112×96	No	The cheat puzzle activated with CTRL-Tab in-game
data\sky0-*.dat	Raw VGA Image, 256×256	Yes	Horizon of each track
data\srch0-0.dat	Raw VGA Image, 32×32	Yes	Looks like a radar but seems to be unused
data\table0-*.dat	Unknown format	Yes	These files differ by at most a few bytes, their name suggests a sine table but this is pure speculation. The following pattern appears when they are interpreted as a 256 pixels wide image:
data\textu0-*.dat	Raw VGA image, 64×16384	Yes	64×64 terrain textures
data\title.dat	Raw VGA image, 320×200	Yes	The introductory screen
data\tmaps.dat		Yes	see above
data\tmaps.tab		No	see above
data\track0-0.dat data\track0-0.tab data\track0-1.dat data\track0-1.tab	Unknown format	Yes	Looks unused, game still plays without them
objects/data/tex0-0.dat objects/data/tex0-0.tab	Hi-Octane Texture Atlas, 256×768	No	In-game textures
objects/data/tex0-1.dat objects/data/tex0-1.tab	Hi-Octane Texture Atlas, 256×88	No	In-game textures

Note: none of the TAB files are RNC-compressed.

Notes

General

The image formats above are partially decoded, they are still missing palette information.

All the images are paletted, 8 bits per pixels.

INTRO.DAT

Header can be fixed using Autodesk Animator FLI files fixer but since format is pretty old and that Autodesk Animation Player 1.10 is a legacy Win16 executable, it is not very convenient to use as of today.

Instead, the file can be converted by FFMPEG to either BMP or AVI,

Convert the animation to individual images, handle last invalid frame:

<syntaxhighlight lang="text"> ffmpeg -i INTRO.DAT -vframes 548 -pix_fmt bgr24 intro%03d.bmp </syntaxhightlight>

Convert the sequence of images to a raw AVI and respect the original frame rate:

<syntaxhighlight lang="text"> ffmpeg -r 14 -i intro%03d.bmp -vcodec rawvideo intro.avi </syntaxhightlight>

Note that since the underlying format does not handle audio, there won't be any.

Credits (in alphabetical order)

Aybe

Malvineous

movAX13h

srtuss

Syndicate series unofficial fan site for the various utilities.

Links

Game demo, Network and MPU-401 patches

Hi-Octane + General MIDI = crash?