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Comment: Added changed script property


Our goal is to keep breaking changes between any given version of X4 to an absolute minimum. In some cases, however, we have had to change things which break scripts/mods which were written for older versions.
The following table provides an overview about all breaking changes. This should help you to make any necessary changes to restore compatibility of older mods with new versions of X4.
Feel free to drop a note if a certain breaking change is breaking your mod and you have difficulties finding a way to work around the issue.


The list of breaking changes does NOT cover changes in the provided/shipped Lua scripts (for instance UI scripts like the ones located under ui/addons/XXX or ui/core/Lua). These scripts can change anytime without explicit notice. If you hook into one of these scripts or provide replacements for these, please check the script for possible breaking changes yourself.

Further note that the list provides information about breaking changes which are in the pipeline of being released. This is meant merely as an informational heads up. Neither do mistake this as an announcement of that version becoming available soon nor take it as a fact for granted that such a change will go live. Any information provided for not yet released versions can change (and even be removed) prior to such version having seen the light of day.

As a final note, please be aware that issues introduced during the beta phase might not be explicitly mentioned in the list below, if things would only be broken in-between two beta versions. While we still aim to document any (potential) breaking change here, there might be circumstances for which we divert from that procedure (especially in case of only minor issues which are considered merely bugfixes rather than an intended behavior change).

titleUI modding considered unstable until further notice...

Please note that UI modding must be considered unstable in the current version. While we are working hard to get the UI modding integration into a stable state, we might have to introduce larger backwards incompatibilities in the following patches. This means that you might have to modify any mod using UI modding capabilities to a larger extend to keep it compatible with certain patches. Still, we are doing our best not to unnecessarily break things for modders and certainly will announce such changes on this page here.


Please note that issues introduced during the beta phase might not be explicitly mentioned as a breaking change, if things would only be broken in-between two beta versions. While we still aim to document any (potential) breaking change here, there might be circumstances for which we divert from that procedure (especially in case of minor issues which is considered merely a bugfix than an intended behavior change).
Feel free to drop a note if a certain breaking change is breaking your mod and you have difficulties finding a way to work around the issue.

Breaking Changes


Breaking Changes



Parameters4.00 Beta 1requiresconstructionvessel parameter moved 
The 'requiresconstructionvessel' attribute has been moved from the 'recycling' node itself, to the new 'station' subnode.
Scripts4.00 Beta 1Changed behaviour of gatedistance script property 
The 'gatedistance' script property now minimizes the number of gate jumps instead of counting the number gate jumps in the fastest route. 


UI extensions3.30 Beta 3FFI: Removed GetMissionLimit() and IsMissionLimitEnabled() 
These mission limit-related functions (added in 3.30 Beta 1 and 2) are replaced with FFI IsMissionLimitReached()


Scripts3.20 Beta 1Parameters of <event_player_attacked_object/> and <event_object_attacked_object/> changed 
Old params: param = attacked object, param2 = attack method, param3 = attacked component
New params: param = attacked object, param2 = attack method, param3 = attack component detail list: [attacked component, attacking weapon]
Note that this also means the component attribute to the events is no longer available, so scripts checking the attacked component need to use event.param3.{1} instead
Scripts3.20 Beta 1

Removed script property $trade.restriction.faction

$trade.restriction.faction has been replaced with $trade.restriction.factions, which returns a list of factions.
UI extensions3.20 Beta 1Lua: GetTradeRestrictions(), ToggleFactionTradeRestriction() and ToggleFactionTradeWareOverride() are now obsolete! 
With the addition of the Trade Rule feature the given functions are obsolete and do not function anymore. This set of functions will return dummy values to avoid breaking scripts. Use GetAllTradeRules(), GetContainerTradeRuleID(), SetContainerTradeRule() and similar trade rule functions as replacement.


Scripts3.10 Beta 1Removed script action <add_build/> 
Removed <add_build/> action which was no longer needed and would result in builds being added in unsupported ways. Use other <add_build_xxx/> actions.


Scripts3.0 Beta 6Changed behaviour of script action <get_suitable_job/> 
<get_suitable_job/> previously did not respect job quotas or the current number of job ships. It now does, only returning job IDs which are not exceeding the maxgalaxy quota. Using 'exceedquota' allows the action to behave as before.
Scripts3.0 Beta 6Changed behaviour of script action <get_ware_definition/> 
<get_ware_definition/> previously filtered for equipment wares by default. This is now not the case and existing cases now use flags="equipment". Additional filter attributes for group and tags has also been added.
Global3.0 Beta 5Renamed all files in the md, ui, and cutscenes folders to lower-case 

All MD, UI, and cutscene files have been renamed as lower-case. For most users this should have no effect since files packed in catalogs are essentially case-insensitive. However, this change can affect users on Linux systems when running a mod that contains single files instead of a catalog, and/or when playing with unpacked base game files. If your mod has XML patch files that are not packed in a catalog, the filenames must be lower-case to match the filenames in the base game. (For info on using mod catalogs, see the Readme of the X Catalog Tool.)

Note that this change has no effect on the actual content of scripts or cutscenes. The MD script/cutscene names are stored in the files, regardless of the filenames, so that references to them remain unchanged (e.g., "md.Setup.Start" references a cue in setup.xml).

Scripts3.0 Beta 5Adjustments of some MD library cues in the base game to change their usage from <include_actions> to <run_actions> 
Some MD library cues in the base game that were previously used with <include_actions> have been adjusted, so they must now be used with the new MD action <run_actions> instead. Mods that use such a library with <include_actions> will have to switch to <run_actions> as well. A list of affected libraries is not provided here. Note: Additional library cues may be adjusted in future builds without further warning.
Scripts3.0 Beta 5Changes to $dockingbay.todockpos and $dockingbay.launchpos 
Before the change, positions are relative to $dockingbay.parent.
After the change, positions are relative to $dockingbay as specified in the documentation.
Global3.0 Beta 2Support for entity flag "skillsvisible" dropped 
Entity skills are always visible; that flag was a leftover from XR. We removed support for the script property .skillsvisible, the attribute "skillsvisible" of <set_entity_traits> and <set_npc_template_traits>, and the parameter "skillsvisible" of Lua function GetComponentData().
Scripts3.0 Beta 2Changes to <event_object_changed_owner> and added <event_object_changed_true_owner>. 
Before 3.0 Beta 2 there was just a single <event_object_changed_owner> condition. This condition was triggered in multiple cases when an owner change occurred. However, the exact cases were inconsistent and also the event could have been triggered w/o an effective owner change having been applied.
3.0 Beta 2 fixes these inconsistencies and ensures that the event is only fired, if the "effective" component owner of the object changed. To handle cases where the script actually needs to be informed if the "true" owner of a component was changed (i.e. not taking the cover faction into account) a new <event_object_changed_true_owner> was introduced.
If in your scripts you make use of the <event_object_changed_owner> condition you need to verify that you indeed want to work with the "effective" component owner or whether your script code actually should work with the true owner of an object and update your code accordingly.
On top of that the 3rd parameter of <event_object_changed_owner> (trueprevious) was dropped as the event is no longer triggered upon a change of the true owner alone (i.e. only if the change of the true owner has also an effect on the "effective" component owner).
Global3.0 Beta 1MissionBoard support dropped 
MissionBoards was a dummy asset type which was only used during early development and never meant to be shipped in the released version. If any mod tried to make use of this asset type, undefined behaviour would occur. Therefore we cleaned things up in 3.0 Beta 1 including deprecating/removing any related UI/script function.
Job/God3.0 Beta 1By default, job/god entries now only spawn objects in space added by the extension in which they are defined 
To better support extensions which add to the base game map, a job/god entry now defaults to only spawning objects in areas of the map that are added by the extension in which that entry is defined. You can override this behaviour by adding a matchextension="false" attribute to the job/god entry definition. This allows the entry to spawn objects anywhere that matches the entry's other criteria.
Scripts3.0 Beta 1Script action <add_actor_to_room/> attribute 'room' renamed to 'object' 
Due to engine changes, script action <add_actor_to_room/> has had the attribute 'room' changed to 'object', which is more accurate. Most likely requires a 'position' if a slot is not provided.
Scripts3.0 Beta 1Script action <set_doors_locked/> attribute 'group' changed 
The 'group' attribute of <set_doors_locked/> can no longer be a list. It must be a single tag value. Previously, a list containing one tag was accepted, which was redundant.
Scripts3.0 Beta 1Script conditions <event_hack_*/> and <event_controlpanel_hack_*/> removed 
These events were never triggered, with the exception of <event_hack_started/> on the player entity for instant control panel hacks. Use <event_player_hacked_object> instead.
Scripts3.0 Beta 1Script actions <set_hack_target/> and <abort_hack/> removed 
These actions had no effect and were removed.
Scripts3.0 Beta 1<setup_conversation_minigame/> script action removed 
The script action was a leftover from the XR era and was never supported in X4 and couldn't be used in a meaningful way. It was therefore decided to better drop it altogether as it's not expected having been used by any mods.
Scripts3.0 Beta 1<add_player_choice_*> confidence attribute removed 
The default confidence of player options is another leftover from the XR era and had no effect in X4.
Scripts3.0 Beta 1<hack_via_control_panel/> script action removed 
Unused script action <hack_via_control_panel/> was removed.
UI core3.0 Beta 1Lua: GetMiniGameCursorPosition() removed 
GetMiniGameCursorPosition() was a left over from the XR era and never supposed to be shipped with X4. The function practically always returned 0 and hence we don't expect the removal of this obsolete function causing any actual mod to break.
UI core3.0 Beta 1FFI: GetLocalizedInteractiveNotificationKey can return icon placeholders 
In 3.0 Beta 1 we added support to display icons for keyboard bindings, if an icon is available for the specified keys. This results in GetLocalizedInteractiveNotificationKey() potentially returning a different text now if such an icon is assigned to the mapped key/button.
UI extensions3.0 Beta 1FFI: UIWeaponMod returned by GetInstalledWeaponMod() now includes property SurfaceElementFactor 
In 3.0 Beta 1 we added support for a new weapon mod property "SurfaceElementFactor" to allow weapons to deal increased damage to surface elements such as Shield Generators, Turrets or Engines.
Scripts3.0 Beta 1$ware.illegal updated 
$ware.illegal used to return true if the specified ware has the 'illegal' tag which is no longer used.
It now returns true if $ware is illegal to any faction in the game.
Scripts3.0 Beta 1MD script RML_Flight_Along_Path removed 
The MD script RML_Flight_Along_Path was not referened and was removed.
Scripts3.0 Beta 1parameters of <event_venture_mission_completed/> changed 
old params: param = venture details, param2 = ships involved, param3 = duration
new params: param = venture detail list: [mission name, mission type], param2 = list of ships involved, param3 = duration
Scripts3.0 Beta 1

<set_object_wing_name/> removed,
<set_object_fleet_name/> added

The common action <set_object_wing_name/> has been replaced with <set_object_fleet_name/>
Scripts3.0 Beta 1

$controllable.wing.* removed,
$controllable.fleet.* added

$, $controllable.wing.iscommander, and $controllable.wing.commander have been replaced with $, $controllable.fleet.iscommander, and $controllable.fleet.commander


Scripts2.60 Beta 1'checkoperational' filter behaviour changed 

Actions and conditions which use the 'checkoperational' filter now behave differently. Instead of changing how 'class' and 'exactclass' behave, checkoperational == true adds an additional filter for the components being of state operational, equivalent to state="componentstate.operational". This is implicitly enabled in action elements (e.g. <find_.../>) or condition elements (e.g. <count_...>), meaning that find_ship will only find operational ships. Using such actions/conditions with checkoperational="false" will include non-operational components such as wrecked and constructions. Existing uses may find that results now exclude non-operational components.

Sub nodes such as match_child will have checkoperational default to false. Existing uses may find that results now include non-operational components.

Scripts2.60 Beta 1$container.supplyresources behavior changed 

The script keyword $container.supplyresources now includes reserved wares.


UI core2.20 Beta 3/4Lua: GetControllerInfo() returned mouseSteering/mouseCursor values are undefined. 

2.20 Beta 3 introduced the new direct mouse steering mode. The mode was however not integrated as a first level mode and hence GetControllerInfo() returned the "gamepad" mode while direct mouse steering was active.
In 2.20 Beta 4 we improved the situation slightly so that a call to GetControllerInfo() will return either "mouseCursor" or "mouseSteering" in any of the 3 mouse modes.

It's a pending change to ensure that the returned mode is more reasonable in an upcoming patch. So be aware that another breaking change might be introduced at some point.

Scripts2.20 Beta 3Attribute for build related conditions e.g. <event_build_finished/> renamed from 'buildmodule' to 'buildprocessor' 
The underlying behaviour remains the same in that it involves the buildprocessor, not the buildmodule. The attribute name has simply been corrected.


Scripts2.00 Beta 1<event_build_finished/> param2 now returns null instead of a construction sequence 
The construction sequence which was finished should now be accessed via the buildtask provided via param3.
Scripts2.00 Beta 1param.boarding.{...} strength parameters removed 
The 'recruitstrength', 'veteranstrength' and 'elitestrength' script parameters were no longer required for balancing the boarding gameplay, and were removed.
Scripts2.00 Beta 1$defensible.boardee/$defensible.boarder and <set_object_boarder/>/<remove_object_boarder/> removed 
Due to changes to boarding in X4, the boarding connections accessed by these script properties and actions became redundent and thus, removed. Any connections set by these actions in a savegame will not survive loading.
UI extensions2.00 Beta 1FFI: GetUpgradeSlotCurrentComponent()/GetUpgradeSlotGroup() works on non-operationals 
Before 2.0 Beta 1 using GetUpgradeSlotCurrentComponent() or GetUpgradeSlotGroup() only performed on operational objects (i.e. not wrecked objects or objects under construction). Since this is inconsistent with the rest of the UI functions, this was considered a bug and fixed in 2.0 Beta 1. If you require the old behavior, use the FFI function: IsComponentOperational() to check the passed object's state before making the call.
UI extensions2.0 00 Beta 1FFI: SetFormationShape() no longer indicates an error upon certain error cases 

Before 2.0 Beta 1 a call to SetFormationShape() indicated an error state to the caller in certain cases where setting a formation shape (potentially) failed. Due to a design flaw in the handling of formations, this however doesn't do any good, since the function by itself doesn't really set the formation shape in all cases. On top of that the call can fail at random. Hence, at the moment an indication of an error case that setting a formation potentially fails is no good to the caller and he has no means to distinguish that case from a real error case.
Therefore, in 2.0 Beta 1 we drop the error indication in case of an attempt to set the formation fails. We are currently working on a better solution to the underlying problem and hope to have it ready as part of a following beta.

Scripts2.00 Beta 1<create_formation/> now requires the attributes: 'leader' and 'follower'. Attribute 'object' is now deprecated. 
This now enforces a leader and at least one follower in order to create or change a formation.  Former implementation made it possible to create formations without any followers which led to issues.
Scripts2.00 Beta 1<event_player_changed_target/> now fires and returns null if the player deselects a target. 
For prior behavior, check for event.param being non-null.
AI Scripts2.00 Beta 1

<shoot/>/<shoot_at/> attribute changes.


Changed: Attribute "primary" is now optional and defines whether weapons from the ship's active primary weapon group will be fired. Defaults to true.
New attribute: "secondary" is an optional attribute that defines whether weapons from the ship's active secondary weapon group will be fired. Defaults to true.
New attribute: "missiles" is an optional attribute that defines whether only missile launchers will be used. If false, only guns will be fired. Defaults to false.

Corrects now-obsolete assumption that primary weapon groups only contain guns and secondary weapon groups only contain missile launchers.

UI extensions2.00 Beta 1FFI: GetBuildTask()/GetNumBuildTasks() got a new "buildmoduleid" parameter.  
Added possibility to query build tasks of a certain buildmodule.
UI extensions2.00 Beta 1Lua: GetLibraryEntry() retrieved a new "buildresources" field. 
Added list of resources a buildmodule needs to build.
UI extensions2.00 Beta 1Lua: CalculateTotalHullFraction() was removed.  
Unused, derelict function from XR - use GetComponentData(..., "hullpercent") instead.
UI extensions2.00 Beta 1FFI: RequestDockAtReason()/UndockPlayerShip() changed their return values.  
Changed return value type to const char* to better identify failure reasons in Lua script.


UI extensions1.50 Beta 3Lua: GetComponentData() changed behavior of "docksizes" propertly.  
The "docksizes" property no longer includes internal ship storage docks.
All1.50 Beta 2Meaning of "Shipyard" was corrected throughout Lua/MD/AI scripts, so that Wharfs are not Shipyards (unlike in XR). 

Shipyards (formerly also known as Capital Shipyards) can build capital ships, while Wharfs only build non-capital ships. To check whether a station is a Shipyard or a Wharf, check whether the station "can build ships".

Lua: Adjusted GetComponentData() and HasShipyard(), added HasWharf()
Lua / GetComponentData() properties: Removed "iscapitalshipyard", fixed "isshipyard", added "canbuildships", "iswharf", "isequipmentdock"
Scripts: Fixed property .isshipyard, added .iswharf (.canbuildships existed already)

UI extensions1.50 Beta 2FFI: UpgradeGroupInfo datatype was changed.  
Added new "operational" field to retrieve information about number of operational upgrades in a group.
UI extensions1.50 Beta 1FFI: SetGuidance() removed useinfopoint argument. 

In X Rebirth "info points" existed (which were mainly used as interaction points to scan stations/access information about modules). These were removed in X4 but this left-over property here was missed to be removed in-time for release. It was therefore removed now in order to move towards a stable/clean UI API.

The new function declaration is: void SetGuidance(UniverseID componentid, UIPosRot offset)

UI extensions1.50 Beta 1FFI: CancelConstruction() changed its return value.  
CancelConstruction() now returns if the cancellation was successful. 


UI extensions1.32Lua: GetComponentData() removed the "nextdestname" property. 
Instead of "nextdestname", use the properties "destination" or "destinationsector" to retrieve a destination component, then retrieve its "name" property.


UI extensions1.20FFI: GetAAOption() got a new "useconfig" parameter.  
The AA setting was changed to check the new setting with the user. In order to restore the old setting GetAAOption() gets the option to retrieve the config settings.