OOP

Object Orientated Programming is introduced in MTA:SA 1.4 and comes with special utility classes like Vector and Matrix. This page contains general information about the OOP functions and provides useful links.

Turning it on

By default, OOP is disabled - this is mainly because the vast majority of servers will prefer to stick to what they know - procedural programming. In fact, functions are still available even when OOP is enabled, just like vectors and matrices are always available, regardless of whether OOP is enabled or disabled. Enabling OOP is as simple as adding the following line to the resource meta file:

<oop>true</oop>

Vectors and Matrices

Vectors and Matrices make it easier to drop the complex maths and go straight ahead with fun part of maths. As mentioned above, OOP does not have to be enabled in the server config for this to be enabled.

OOP Metatable Structure

You will undersand this if you're an advanced scripter with an understanding in metatables.

-- Exposed to global environment
Element = {
    create = createElement,
    setPosition = setElementPosition,
    ...
}

Vehicle = {
    create = createVehicle,
    setColor = setVehicleColor,
    ...
}

-- Hidden in lua registry, applied to userdata
ElementMT = {
    __index = CLuaClassDefs::Index,
    __newindex = CLuaClassDefs::NewIndex,
    __class = Element,
    __call = __class.create,
    __set = {
        type = CLuaClassDefs::ReadOnly,
        health = setElementHealth,
        ...
    },
    __get = {
        type = getElementType,
        health = getElementHealth,
        ...
    },
}

VehicleMT = {
    __index = CLuaClassDefs::Index,
    __newindex = CLuaClassDefs::NewIndex,
    __class = Vehicle,
    __parent = ElementMT,
    __call = __class.create,
    __set = {
        damageProof = setVehicleDamageProof
        ...
    },
    __get = {
        damageProof = isVehicleDamageProof
        ...
    },
}

Things to do

• Document all the existing functions in OOP form on the documentation

Useful Links

• OOP Introduction - teaches you about the basics of OOP
• Function list (client) - the most up to date list of functions, you should be able to infer from this.
• Function list (server) - the most up to date list of functions, you should be able to infer from this.