Modrules.lua

Location

modrules.lua is a file in the Gamedata/ directory of a Spring game.

Purpose

This file controls various global parameters of the game, for example how fast units gain experience, what unit types can be transported, how fine grained the LOS system is, etc.

Source

The engine source code which parses the data from this file is viewable here:

rts/Sim/Misc/ModInfo.cpp

Data Types

int: An integer number. eg. 5
float: A number with decimals. eg 1.023
bool: A value which can be true or false. eg true
string: Text, or more precisely a string of alphanumeric characters. eg "string of characters"
rgb: Three float components, representing red, green and blue components, ranged from 0.0 to 1.0. eg {0.0, 0.0, 0.0}
float3: Three float components, eg {0.0, 0.0, 0.0}
float4: Four float components, eg {0.0, 0.0, 0.0, 0.0}

Details

Modrules.lua is divided into several sub-tables containing tags specific to each section, as follows:

capture

float energyCostFactor default: 0.0

How much of the original energy cost it requires to capture something.

construction

bool constructionDecay default: true

Do uncompleted building frames begin to decay if no builder is working on them?

float constructionDecayTime default: 6.66

The time in seconds before abandoned building frames begin to decay.

float constructionDecaySpeed default: 0.03

How fast build progress decays for abandoned building frames. Note that the rate is inversely proportional to the buildtime i.e. a building with a larger buildtime will decay more slowly for a given value of this tag than a building with a shorter buildtime.

experience

float experienceMult default: 1.0

Controls the amount of experience gained by units engaging in combat. The formulae used are:

xp for damage = 0.1 * experienceMult * damage / target_HP * target_power / attacker_power

xp for kill = 0.1 * experienceMult * target_power / attacker_power.

Where power can be set by the UnitDef tag.

float powerScale default: 1.0

Controls how gaining experience changes the relative power of the unit. The formula used is Power multiplier = powerScale * (1 + xp / (xp + 1)).

float healthScale default: 0.7

Controls how gaining experience increases the maxDamage (total hitpoints) of the unit. The formula used is Health multiplier = healthScale * (1 + xp / (xp + 1)).

float reloadScale default: 0.4

Controls how gaining experience decreases the reloadTime of the unit's weapons. The formula used is Rate of fire multiplier = reloadScale * (1 + xp / (xp + 1)).

featureLOS

int featureVisibility default: 3

Controls the visibility of features. Can be 0 - no default LOS for features, 1 - Gaia features always visible, 2 - allyteam & Gaia features always visible, or 3 - all features always visible.

fireAtDead

bool fireAtKilled default: false

Will units continue to target and fire on enemies which are running their Killed() animation? (See Animation-LuaCallins#Generic)

bool fireAtCrashing default: false

Will units continue to target and fire on enemy aircraft which are in the 'crashing' state? (See Lua_SyncedCtrl#Unit_Control)

flankingBonus

int defaultMode default: 1

The default flankingBonusMode for units. Can be 0 - No flanking bonus. Mode 1 builds up the ability to move over time, and swings to face attacks, but does not respect the way the unit is facing. Mode 2 also can swing, but moves with the unit as it turns. Mode 3 stays with the unit as it turns and otherwise doesn't move, the ideal mode to simulate something such as tank armour.

los

int losMipLevel default: 1

Controls the resolution of the LOS calculations. A higher value means lower resolution but increased performance. An increase by one level means half the resolution of the LOS map in both x and y direction. Must be between 0 and 6 inclusive.

float losMul default: 1.0 Removed from version 101.0

Multiplies all unit's sightDistance by this value. Generally speaking you should always use the default.

int airMipLevel default: 1

Controls the resolution of the LOS vs. aircraft calculations. A higher value means lower resolution but increased performance. An increase by one level means half the resolution of the air-LOS map in both x and y direction. Must be between 0 and 30 inclusive. [1] - jK describe for you what the value means.

float airLosMul default: 1.0 Removed from version 101.0

Multiplies all unit's airSightDistance by this value. Generally speaking you should always use the default.

int radarMipLevel default: 2

Controls the resolution of the radar. See description of airMipLevel for details.

movement

bool allowAirPlanesToLeaveMap default: true

Are (gunship) aircraft allowed to fly outside the bounds of the map?

bool allowAircraftToHitGround default: true New in version 90.0

Are aircraft allowed to hit the ground whilst manoeuvring?

bool allowPushingEnemyUnits default: false New in version 83.0

Can enemy ground units push each other during collisions?

bool allowCrushingAlliedUnits default: false New in version 85.0

Can allied ground units crush each other during collisions? Units still have to be explicitly set as crushable using the crushable parameter of Spring.SetUnitBlocking.

bool allowUnitCollisionDamage default: false New in version 85.0

Do unit-unit (skidding) collisions cause damage?

bool allowUnitCollisionOverlap default: true New in version 89.0

Can mobile units collision volumes overlap one another? Allows unit movement like this (video) at the cost of more 'clumping'.

bool allowGroundUnitGravity default: true New in version 92.0

Allows fast moving mobile units to 'catch air' as they move over terrain.

bool allowHoverUnitStrafing default: true if using QTPFS pathfinder New in version 92.0

Allows hovercraft units to slide in turns.

bool useClassicGroundMoveType default: false New in version 89.0 Removed from version 102.0

A ticket back to unit movement circa 2009: no reversing, no turninplace = false, no smooth collision handling, no nothing. For comparison of pathfinding code.

paralyze

bool paralyzeOnMaxHealth default: true

Are units paralyzed when the level of emp is greater than their current health or their maximum health?

reclaim

int multiReclaim default: 0

Can multiple units reclaim a feature or only one? 0 implies the latter, all other values the former.

int reclaimMethod default: 1

Controls how features are reclaimed. Can be 0 - gradual reclaim, 1 - all reclaimed at end, any other positive value n - reclaim in n chunks.

int unitMethod default: 1

Controls how units are reclaimed. Can be 0 - gradual reclaim, 1 - all reclaimed at end, any other positive value n - reclaim in n chunks.

float featureEnergyCostFactor default: 0.0

How much energy should reclaiming a feature cost? Multiplier against the fraction of the features' metal content reclaimed.

float unitEnergyCostFactor default: 0.0

How much energy should reclaiming a unit cost? Multiplier against the fraction of the unit's buildCostEnergy reclaimed.

float unitEfficiency default: 1.0

How much metal should reclaiming a unit return? Multiplier against the unit's buildCostMetal.

bool allowEnemies default: true

Can enemy units be reclaimed?

bool allowAllies default: true

Can allied units be reclaimed?

repair

float energyCostFactor default: 0.0

How much of the original energy cost it requires to repair something.

resurrect

float energyCostFactor default: 0.5

How much of the original energy cost it requires to resurrect something.

sensors

bool requireSonarUnderWater default: true

If true then when underwater, units only get LOS if they also have sonar.

bool alwaysVisibleOverridesCloaked default: false New in version 101.0

If true then units will be visible even when cloaked (probably?).

bool separateJammers default: true New in version 101.0

When true each allyTeam only jams their own units.

system

int pathFinderSystem default: 0 New in version 85.0

Which pathfinder does the game use? Can be 0 - The legacy default pathfinder, 1 - Quad-Tree Pathfinder System (QTPFS) or -1 - disabled.

float pathFinderUpdateRate default: 0.007 New in version 98.0

Controls how often the pathfinder updates; larger values means more rapid updates.

float pathFinderRawDistMult default: 1.25 New in version 105.+ BAR

Engine does raw move with a limited distance, this multiplier adjusts that

bool allowTake default: true New in version 103.0

Enables and disables the /take UI command.

transportability

bool transportAir default: false

Can aircraft be transported?

bool transportShip default: false

Can ships be transported?

bool transportHover default: false

Can hovercraft be transported?

bool transportGround default: true

Can ground units be transported?

bool targetableTransportedUnits default: false New in version 89.0

Can transported units be targeted by weapons? true allows both manual and automatic targeting.

Examples

Empty

modrules.lua can simply return an empty table like this:

return {}

If you do this, Spring will use the default values.

Configurable by modoptions

Interestingly modrules.lua can read modoptions, so these parameters can be scripted to be configurable from the lobby. For example to allow selecting either legacy default pathfinder or QTPFS via a modoption:

  system = {
    pathFinderSystem = (Spring.GetModOptions() and (Spring.GetModOptions().qtpfs == "1") and 1) or 0,
  },

External Examples

'Evolution RTS' Modrules.lua