Unit Building Basics

Every TA unit needs three parts: FBI (definition), 3DO (model), BOS/COB (script).

1. The FBI file

A plain text file with key=value; lines. The most important fields:

[UNITINFO]
{
  unitname=FLASH;
  name=Flash;
  description=Fast Attack Vehicle;
  buildcostmetal=135;
  buildcostenergy=705;
  buildtime=1890;
  maxdamage=420;
  LOSight=390;
  weapon1=EMG;
  badtargetcategory=NOTAIR;
  movementclass=TANKSMALL;
  ...and so on.
}

• buildcostmetal/energy + buildtime → balance.
• maxdamage → hit points.
• weapon1..3 → references to weapons defined in weapons.tdf.
• movementclass → which terrain type the unit can traverse (from movement.tdf).

2. The 3DO model

Cavedog’s proprietary 3D format. Tools like UpSpring or older 3DO converters import from 3DS/OBJ models. Important: pieces (movable parts) must be named, because the BOS script addresses them by name.

3. The BOS/COB script

BOS = source language, compiled to COB. Controls:

• Create() — initialization
• StartMoving()/StopMoving() — driving sounds
• AimFromPrimary()/AimPrimary() — weapon aiming
• Shot1() — firing, effects
• Killed() — destruction animation

Example (schematic):

FlashPiece torso, turret, gun;

Create() {
  hide gun;
  show turret;
}

AimFromPrimary(piecenum) { piecenum = turret; }

AimPrimary(heading, pitch) {
  turn turret to y-axis heading now;
  return TRUE;
}

Installation

1. UFO file (or individual files packed into an HPI) into the TA folder.
2. If it’s a new unit category: extend the side patch / units list — details on File Universe under “Third Party Units Anleitung”.

Balance tips

• Always start from existing units as reference (copy Flash stats, then adjust).
• DPM = damage × rate of fire → compare against cost for rough fairness.
• Don’t overdo LOSight — see the LoS bug (max. 288px without patch).

Sources

• Unit Creation Tutorial (TA Universe)
• File Universe: tools like BOS compilers, UpSpring, FBI editors.