The EAX Scripting language

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Project X scripts are based on a custom scripting language, named EAX, its syntax is similar to c++, with a number of singularities.


Local variables need local identifier

local k = 5;

EAX doesnt need variable declarations, nor type. Variables are allocated upon the first use, and type is determined with iterational solver, for example:

local variable = GetFirstWorm();

Variable will be of type CWorm, and initialized with GetFirstWorm() return value.


Class fields do not need declaration, nor type, and can be defined anywhere in class methods:

override void CWorm::CWorm(CObject* Parent,int aTeam,int aIndex,CWormParams* params) 
    field = 5;

The super macro

This macro, whose syntax is super( BASE CLASS ARGUMENTS ), can be used to call base class (game original class) method, for example:

override void CWorm::FireFinal(CWeapon* Weap,CShootDesc* Desc)
   local Weapon = GetWeaponByName("Bazooka");
   super(&Weapon, Desc);

second line calls CWorm::FireFinal() with custom arguments.

If we derivate a class like:

CWormA : CWorm;

And then define method:

CWormA::FireFinal(CWeapon* Weap,CShootDesc* Desc)
   local Weapon = GetWeaponByName("Bazooka");
   super(&Weapon, Desc);

Second line will ALSO call CWorm::Firefinal();

Overriding Game Functions

Identifier override is used to override execution of game functions to add custom routines, for example:

override void CMissile::ExplodeAt(fixed x,fixed y)
   j = x/2;

will call original function with parameter x at half value.

The require identifier

Used to include libraries in the code:

require utils;

Include utils library.