Difference between revisions of "Lua-based equipment"

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   * cargo_life_support=1,
 
   * cargo_life_support=1,
 
   * autopilot=1
 
   * autopilot=1
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 +
=== Creating equipment ===
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There are basically two ways to create a new piece of equipment for Pioneer.
 +
 +
==== The fast way ====
 +
You can just instantiate a new EquipType. Its only argument is a table whose only mandatory content are a <code>modifiers</code> table with the modifiers to apply at install time and a <code>slots</code> with the name of the slots to install the piece in, stored in the array part of the table. The rest of the table content will get copied in the new object.
 +
 +
Here is the creation of the basic ECM, for instance.
 +
<pre>
 +
ecm_basic = EquipType.new({
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    name="Basic ECM", description="",
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    slots="ecm", price=600000, modifiers={mass=2000, ecm_power=2}
 +
})
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</pre>
 +
Since there is only one slot to install it in, you can just use a single string instead of a full table.
 +
 +
Please bear in mind that the object created this way will be stored as reference every time it gets installed, if you want each piece to be its own object you will have to use another method.
 +
 +
Note that for more specific pieces of equipment such as hyperdrives, you would use HyperdriveType instead of EquipType, with its own specifications.
 +
 +
TODO: Document HyperdriveType

Revision as of 13:05, 2 March 2013

As of March 2013, there's been an ongoing effort for about a year to rewrite the equipment system to be able to define and modify random pieces of equipment through Lua. The resulting system is entirely Lua-based, and communicates with C++ only through string->integers pairs called modifiers.

From the C++ side

If you wish to know if there is an ECM installed on ship, you would just do

int ecm_mod = ship->GetModifier("ecm"); // This gets you the actual value of the modifier, ie the strength of the ECM
if (ecm_mod > 0) {
    BlastAwayThisMissileWithStrength(ecm_mod);
}

As the UI is being ported to new-ui and thus is defined in Lua, you shouldn't need to access the equipment directly. If you need more interaction with the equipment than simple modifiers, as it will probably be the case for lasers (not yet implemented at the time of writing), it might be worth it to write specific Lua interfaces that are to be called by the relevant pieces of equipment at install/uninstall time.

TODO: A list of all the modifiers used in the C++ code.

From the Lua side

Accessing the equipment

The Lua interface to fetch, count, etc, the equipment hasn't changed much, I tried to keep the API changes to a minimum. The difference is that instead of manipulating constants (well, strings) you will use straight Lua object. For instance, instead of Game.player:AddEquip("HYDROGEN", 2) You'll write Game.player:AddEquip(cargo.hydrogen, 2)

The canonical equipment is stored in 2 tables, equipment and cargo The slot names are not in caps anymore, and are the following (with their default size):

 * cargo=0,
 * engine=1,
 * laser_front=1,
 * laser_rear=0,
 * missile=0,
 * ecm=1,
 * scanner=1,
 * radar=1,
 * hypercloud=1,
 * hull_autorepair=1,
 * energy_booster=1,
 * atmo_shield=1,
 * cabin=50,
 * shield=9999,
 * fuel_scoop=1,
 * cargo_scoop=1,
 * laser_cooler=1,
 * cargo_life_support=1,
 * autopilot=1

Creating equipment

There are basically two ways to create a new piece of equipment for Pioneer.

The fast way

You can just instantiate a new EquipType. Its only argument is a table whose only mandatory content are a modifiers table with the modifiers to apply at install time and a slots with the name of the slots to install the piece in, stored in the array part of the table. The rest of the table content will get copied in the new object.

Here is the creation of the basic ECM, for instance.

ecm_basic = EquipType.new({
    name="Basic ECM", description="",
    slots="ecm", price=600000, modifiers={mass=2000, ecm_power=2}
})

Since there is only one slot to install it in, you can just use a single string instead of a full table.

Please bear in mind that the object created this way will be stored as reference every time it gets installed, if you want each piece to be its own object you will have to use another method.

Note that for more specific pieces of equipment such as hyperdrives, you would use HyperdriveType instead of EquipType, with its own specifications.

TODO: Document HyperdriveType