Running changelog

This is the bleeding-edge changelog since version 2025.04.11, for pre-release 2025.06.

Caveats

redid air drag calculation for ground units thrown into the air.
unit shaders receive TRS transforms instead of matrices, breaking shaders and the ability to have anisotropic piece scaling. See the “Smooth script piece animations” section below.
non-turreted units now rotate themselves to face the target if needed. See below for details.
removed ^123 style texture referencing for unit def icons for gl.Texture and similar interfaces. There is a new set of icon-related callouts, see below.
removed Python bindings for AI. Apparently unmaintained and unused.
removed UpdateWeaponVectorsMT, UpdateBoundingVolumeMT, and AnimationMT springsettings. These were just in case, but MT seems safe enough after some time live testing.
removed /AdvModelShading command and the AdvUnitShading springsetting, the adv mode is now always on. In practice there wasn’t any difference since GLSL became mandatory.
removed gl.UnitGL4, gl.FeatureGL4, gl.FeatureShapeGL4, and gl.UnitShapeGL4. These did not do anything.
handicap (native income multiplier) no longer applies to reclaim. Use gadget:Allow{Unit,Feature}BuildStep to replace, if desired. Backwards compatibility feature check: Engine.FeatureSupport.noHandicapForReclaim.
/group add N no longer selects the entire group, just adds. /groupN (without space) unaffected. Feature support tag: Engine.FeatureSupport.groupAddDoesntSelect.
immobile units that canKamikaze no longer disregard the blocking unit def tag.
BeamLaser and LightningCannon type weapons now pass their actual projectileID to callins rather than -1.
BeamLaser and LightningCannon now obey ellipsoid and/or cylinder target volumes correctly and obey the targetBorder tag correctly, this will result in a slightly different effective range volume.
added a bunch of modrules allowing to configure how units with the Guard command move in relation to their guardee, see below for details. The caveat is that the default values changed as well.
replay filenames now include full map name rather than cropped to first dot.
in-line text color codes: 0x11 and 0x12 (decimal 17 and 18) now work as color code indicators, in addition to 255 and 254 respectively. Engine.textColorCodes still only lists the old ones.
engine no longer loads shaders/GLSL/GroundDecalsFragProg.glsl and shaders/GLSL/GroundDecalsVertProg.glsl directly. Instead engine now loads shaders/GLSL/groundDecals.lua which should return a { vertex = "path", fragment = "path" } table.
default value for LogRepeatLimit springsetting 10 → 0, see below.
area resurrect command now puts a leash on repair sub-commands (behaviour change, but also the repair subcommands now have 5 args instead of 1).
widgets can now sign up to receive the widget:Explosion callin. There are some arcane visibility rules that boil down to it revealing much more info than the existing widget:ShockFront callin.
removed the 10 mutator limit, can now have arbitrarily many (this may affect lobbies, autohosts etc who may have assumed the limit).
Spring.ShareTeamResource no longer triggers gadget:AllowResourceTransfer , call it manually if needed.
rmlUI textures use nearest pixel filtering instead of linear. The intended effect is crisper text with anti-aliasing.
Spring.SetProjectileTarget now errors on invalid args instead of silently ignoring.
fully removed support for 32-bit builds.

Deprecation notice

wupget:DrawUnit, DrawFeature, DrawShield and DrawMaterial are deprecated. Nothing changes in behaviour, but they are (and have been for a long time) a bad idea to use as a performance anti-pattern. Use shaders as a replacement.
deprecated Spring.GetUnitCommands(unitID, 0) → number commandCount, use Spring.GetUnitCommandCount(unitID). The non-0 overloads still return a table of commands and are not affected.
similarly deprecated Spring.GetFactoryCommands(unitID, 0), use the new Spring.GetFactoryCommandCount.
deprecated Spring.GetCommandQueue, use Spring.GetUnitCommands (which has always been 100% equivalent), except for the case above.
deprecated the ghostedBuildings engineoption. You can read it manually as a modoption and set every unitdef not to leave ghosts.
at some point in the future engine will stop redistributing dead teams’ unit limit to their allies. See FeatureSupport.deadTeamsKeepUnitLimit and Spring.TransferTeamMaxUnits below.

Features

Non-turreted units rotate towards target

A set of changes aimed to help develop melee units.

units with non-turreted weapons will try to face the target, if all other weapons fail to pass targeting checks. This happens both within the unit’s range (frequently) and outside of it (less frequently).
angle fire tolerance checks won’t apply in case the aimpoint is clipped inside the target (doesn’t happen in all cases, so the tolerance is still something to be aware of of for CQB weapons / units).
non-turreted non-front oriented weapons won’t be handled correctly by the change above for now.
there could be unknown side effects. It’s a test change.

Icon atlases

gl.Texture and alike no longer supports referencing icon textures via ^123 (unit def ID).
icons atlas can now be specified right from gamedata/icontypes.lua, by specifying u0, v0, u1 and v1 (floats 0-1). This way the atlas is not built but loaded.
Spring.AddUnitIcon can now operate with sub coordinates in case of atlased input texture (args 6-9 are now u0, v0, u1, v1 respectively).
add $icons aka $icons0, and $icons1 textures. They respectively represent the initial icons atlas as seen during the game load and a possible atlas that is created for some of the icons got replaced.
add Spring.GetUnitIconData, Spring.GetIconData, Spring.GetAllIconData to mostly get the atlas coordinates. See the API listing for details, the exact interface is still subject to change.

Camera callins

added wupget:CameraRotationChanged(rotX, rotY, rotZ) → nil.
added wupget:CameraPositionChanged(posX, posY, posZ) → nil.

Chat via widgets

added Spring.SendPublicChat(msg) → nil, for sending a chat message. Equivalent to /say.
added Spring.SendAllyChat, and Spring.SendSpectatorChat, same interface as above, for sending chat to allies/spectators. Equivalent to using /say with the “a:” or “s:” magic destination prefixes.
added Spring.SendPrivateChat(msg, playerID) → nil, for sending a private message (aka whisper) to a specific playerID. Almost equivalent to /wbynum, but does not support the magic 255 destination.

GL debugging

added DebugGLReportGroups boolean springsetting, default true. Shows OpenGL push/pop groups in GL debug.
the /debugGL option now takes an optional numerical argument, 0-15. 0 and 1 control the whole debug view without touching anything else (i.e. work as before). Otherwise values 2-15 are treated as a bitmask: 8 controls stacktraces, 4 report groups, 2 the whole debug enabled/disabled state, 1 ignored.

New Website

Slashscreen, in an effort to procrastinate from university finals, completely redid the website.
Reworked the Api docs.
New guides.
Documented RmlUi bindings.

CEG rendering

adds the following tags to CBitmapMuzzleFlame type CEG particles: particleSpeed, particleSpeedSpread, airdrag, gravity. These work the same as they already do for CSimpleParticleSystem type particles.
added animParams1 and animParams2 to CEGs, similar to weapons. Texture 1 is used for CSimpleParticleSystem and the “front” texture of CBitmapMuzzleFlame, texture 2 is used for the “side” texture of muzzle flame. Other CEG classes don’t support this yet. Numberless animParams used as a fallback.
added fixedSideDir, bool default false, to CBitmapMuzzleFlame type CEGs. Tries to tilt the side planes such that they try to be 45 degree to the particle position to camera vector (and 90 degree to each other).

Infotex commands

added /showLoS.
added /showInfoTex foo, where foo is one of the existing info textures (e.g. /showInfoTex elevation is equivalent to /showElevation).
all the /showFoo commands can now accept 0/1, in addition to argument-less toggling.

Smooth script piece animations

unit shaders receive TRS transforms instead of matrices, breaking shaders and the ability to have anisotropic piece scaling. This will require gamedevs to update GL4 shaders that used to employ the engine provided transformation matrices SSBO.
the new method should be both faster and allows smoother animations (interpolated across gameframes).
the new format is not directly documented anywhere, but you can look at basecontent shaders.
added Engine.FeatureSupport.transformsInGL4 backwards compatibility check.

Base64

added Encoding global table (like Spring or math etc), available everywhere. So far contains base64 encoding, more (such as JSON) to be added lated.
added Encoding.EncodeBase64(string plain, bool? stripPadding = true) → string encoded. Can optionally remove the extra = at the end.
added Encoding.DecodeBase64(string encoded) → string plain, decodes a base64 string (if there’s an invalid character, it parses just the valid prefix).
added Encoding.IsValidBase64(string) → bool.
added EncodeBase64Url, DecodeBase64Url, and IsValidBase64Url to Encoding. Same as above, except uses the base64url character set.

Duplicate logs

the LogRepeatLimit springsetting, which controls how many duplicate logs in a row can end up in the infolog, can now accept 0 for infinite.
default value for LogRepeatLimit: 10 → 0
native ingame console no longer filters duplicates (max 1 in a row → infinite)

GLTF/GLB model format support

.gltf and .glb model formats are now supported.
GLTF parser will insert a few empty pieces as root / sub-root.
materials, textures and vertex colors embedded in the GLTF itself are not supported. Mostly because GLTF expects PBR workflow, which the standard engine shader doesn’t do.
GLTF can use a Lua metadata file similar to Assimp, custom model attributes in GLTF can also be used to provide the same data. Supports the existing tags: tex1, tex2, midpos, mins, maxs, height, radius, fliptextures, invertteamcolor.
add a new s3ocompat bool attribute, both for GLTF and Assimp models. Enables the same right handed - left handed flip of the model as it’s done in s3o. This is experimental and probably very bugged. If your model is converted from s3o and animates incorrectly, give this option a try.
does not support re-parenting or the baked rotation angles. Use your 3d editor to change them instead. Assimp not affected.

Ghosts

add leavesGhost unit def tag. Controls whether the unit leaves a ghost. Defaults to true for buildings (maintains previous behaviour).
add leavesGhost UnitDefs entry, same.
add Spring.GetUnitLeavesGhost(unitID) → bool.
add Spring.SetUnitLeavesGhost(unitID, bool leavesGhost, bool? existingGhostRemains = false). If leavesGhost becomes false and the unit already had a ghost, whether the existing ghost is removed or sticks around is controlled by the second arg.
note that the ghostedBuildings engineoption still exists and makes all of the above interfaces no-op, but is scheduled for removal.

Text coloring

added AllowColorFonts bool springsetting, defaults to false. Allows fonts to be colored instead of monochromatic. In practice this means emojis render as expected, though a fancy enough font could also do something to normal text.
in-line text color codes: 0x11 and 0x12 (decimal 17 and 18) now work as color code indicators, in addition to 0xFF and 0xFE (decimal 255 and 254) respectively. The significance of this is that 255/254 are normal, printable characters from reasonable languages so treating them as color codes can ruin otherwise normal text by eating characters and setting random colors.
Engine.textColorCodes still only lists the old ones.
added TextDisableOldColorIndicators bool springsetting, defaults to false. If true, the previous 255 and 254 color codes stop working and Engine.textColorCodes lists the new ones.

Explosion event in unsynced

add Script.SetWatchExplosion(weaponDefID, bool), and the corresponding Get, to unsynced.
widgets can now receive the Explosion callin, same arguments as the gadget one but can’t use the return value to block the CEG. There are some arcane visibility rules (that include the visibility of the explosion’s CEG) that boil down to it revealing a bit more info than the existing widget:ShockFront callin which used to fulfil a similar role.

Team unit limits

add Spring.TransferTeamMaxUnits(fromTeam, toTeam, amount) -> bool success, transfers max unit limit across teams.
add 4th optional boolean arg to Spring.TransferUnit(unitID, teamID, bool? given, bool? transferLimit), default false. If true, also adjusts both teams’ unit limit by 1, making it possible for the transfer to work even if both teams are at limit.
add FeatureSupport.deadTeamsKeepUnitLimit, boolean false. At some point in the future engine will stop redistributing dead teams’ unit limit to their allies.

Death metal

add Spring.CreateUnitWreck(unitID, int? wreckLevel = 1, bool? emitSmoke = true) → featureID?. Creates a wreck as if the unit died.
add Spring.CreateFeatureWreck(featureID, int? wreckLevel = 1, bool? emitSmoke = false) → featureID?. Creates a wreck as if the unit died.
add Spring.AddFeatureDamage with the same signature as Spring.AddUnitDamage. Note that one of the args is paralyze time, but features don’t take paralyze damage.
add a new checkDeath bool arg to Spring.SetFeatureHealth(featureID, health, bool? checkDeath = false). It was discovered that the current behaviour is that features set to negative health don’t die from HP removal and it takes an instance of damage to “poke” them into death. The default of false preserves this, set it to true to let features die immediately from HP removal.
add Spring.SetFeatureFireTime(featureID, fireTime), sets a feature “on fire” (similar to being damaged with a firestarter tagged weapon) with that much time to live, in seconds. Set to 0 to cancel.
add Spring.SetFeatureSmokeTime(featureID, smokeTime), makes the feature emit smoke (similar to freshly killed wrecks) for that many seconds. Note that smoke size is proportional to time remaining.
add the corresponding getters (Spring.GetFeatureFireTime, Spring.GetFeatureSmokeTime) for the above.

Pre-game phase control

add system.useStartPositionSelecter bool modrule. If false, engine won’t eat clicks on startbox during the placement phase.
add synced Spring.SetTeamStartPosition(teamID, x, y, z) -> bool ok.
add synced Spring.SetPlayerReadyState(playerID, bool ready) -> bool ok.
add unsynced Spring.RequestStartPosition(x, y, z, bool? ready) -> nil, sends a request to start at given position. Equivalent to the native picker.

Resource flow

add ‘system.nativeExcessSharing’ modrule, controls whether the resource sharing level (aka “red slider”) applies. Note that this also prevents excess from flowing back to the allyteam. If you want excess to flow to allies and only block changing the share level, use the existing gadget:AllowResourceLevel.
add Game.nativeExcessResource to read back the above.
Spring.ShareTeamResource no longer triggers gadget:AllowResourceTransfer , call it manually if needed.

Unit script piece scaling

Add internal Scale function ancillaries for unit scripts, similar semantics to existing API for Move and Wait. Note that this is a single scalar value (you cannot scale in one dimension).

Spring.UnitScript.IsInScale(piece) -> boolean
Spring.UnitScript.MultiScale(piece, size, speed, ...) -> boolean
Spring.UnitScript.WaitForScale(piece) -> boolean, calls ScaleFinished(piece) when done
Spring.UnitScript.GetPieceScale(piece) -> number
basecontent LUS gadget supports the above (incl. via wrappers where appropriate, same as Move/Turn).

Weapon behaviours

BeamLaser and LightningCannon type weapons now pass their actual projectileID to callins rather than -1.
BeamLaser and LightningCannon now obey ellipsoid and/or cylinder target volumes correctly.
BeamLaser and LightningCannon now have a proper effective range with a non-default value of targetBorder tag.
projectiles colliding with near-vertical cliffs now spawn explosions at the place of collision rather than at the top of the cliff. Applies to all weapon types except DGun.

Modrules for Guard behaviour

Added a bunch of modrules allowing to configure how units with the Guard command move in relation to their guardee.

guard.guardRecalculateThreshold, distance that a guardee must move before the guard goal is recalculated.
guard.guardStoppedProximityGoal, distance that a guardian will stop at nearing a stopped guardee.
guard.guardMovingProximityGoal, extra distance a guardian will keep from a stopped guardee.
guard.guardStoppedExtraDistance, distance the guardian is considered to be in guarding range and will match the velocity.
guard.guardMovingIntervalMultiplier, multiplier for the moving goal while guarding, smaller values will result in higher detail movement but more performance cost.
guard.guardInterceptionLimit, limit for the intercept when a guardian is not in guarding range.

Decals

added $decals texture identifier to access the decals atlas from Lua texturing callouts.
/reloadshaders can now reload decal shaders.
ground decals now have two new quad float attributes for arbitrary custom use, in vec4 userDefined1 at index 10 and in vec4 userDefined2 at index 11. These are the userdata values for quad 0 and 1 respectively as set from Lua.
add Spring.SetGroundDecalUserData(decalID, number quad, number? u1, number? u2, number? u3, number? u4) -> bool ok. Quad has to be 0 or 1 at the moment.
add Spring.GetGroundDecalUserData(decalID, number quad) -> number u1, u2, u3, u4.
engine no longer loads shaders/GLSL/GroundDecalsFragProg.glsl and shaders/GLSL/GroundDecalsVertProg.glsl directly
engine now loads shaders/GLSL/groundDecals.lua which should return a { vertex = "path", fragment = "path" } table
basecontent now contains a default groundDecals.lua implementation which loads the old shaders
add Spring.SetGroundDecalGlowParams(decalID, number? glow, number? glowFalloff) -> bool ok.
add Spring.GetGroundDecalGlowParams(decalID) -> number glow, number glowFalloff.
add a second bool arg and an optional second return value to Spring.GetGroundDecalTextures(bool? mainTex, bool? alsoFilenames = false) → string[] textures, string[]? filenames.

Misc

add Spring.GetPieceProjectileName(pieceProjectileID) -> string name. Returns the name of the source piece for a piece projectile (“body”, “turret” etc). Nil for non-piece projectiles.
add Spring.GetAllProjectiles(bool excludeWeaponProjs = false, bool excludeWeaponProjs = false) -> { proID, proID, ...}.
removed the 10 mutator limit, can now have arbitrarily many.
Lua shader files (i.e. any foo.lua loaded directly by engine for shader purposes) now have access to unsynced VFS functions.
add accurateLeading numerical unit weapon tag (note, not weaponDef). Controls how many extra accuracy iterations are done when calculating shots. 0: current behaviour (single iteration, fails to hit at large speed disparities and/or weird angles). 1: one extra iteration, enough to get a perfect solution for non-ballistic shots and usually good enough for non-extreme ballistic shots too. 2+: extra iterations for ballistic shots, if needed. In practice, shouldn’t need to go higher than low single-digit values. Note that the calculation always stops when 1-frame resolution accuracy is achieved (since unit and projectile movement are all frame-discrete), so setting this arbitrarily high should still be safe and reasonably performant.
math extras (math.hypot, math.normalize, bit ops etc) now available in LuaParser envs (modrules, defs parsing, etc).
added Spring.GetFactoryCommandCount(unitID) → number checks the queue length in a factory’s build queue (note that GetUnitCommandCount is for the rally queue in factories).
add ThreadPinPolicy springsetting to control which CPUs to use. (0) = Off; (1) = System Default; (2) = Exclusive Performance Core; (3) = Share Performance Cores.
added new CEG impact filters, shield and intercepted.
immobile units that canKamikaze (i.e. mines) no longer disregard the blocking unit def tag.
redid air drag calculation for ground units thrown into the air.
add MiniMapDrawPings boolean springsetting, defaults to true. Whether engine renders pulsating white squares on the minimap when a label is placed.
if a factory “changes” a build order into a build order of the same type (e.g. by using command insert) it no longer resets build progress.
/group add N no longer selects the entire group, just adds. /groupN (without space) unaffected. Feature support tag: Engine.FeatureSupport.groupAddDoesntSelect.
expose the rmlUI data model backing table as __GetTable().
add gl.GetEngineModelUniformDataSize(number index) → number sizeInElements, number sizeInBytesOnCPU to grab the size of the model uniforms buffer on the CPU side.
add LuaVBO:CopyTo(otherVBO, sizeInBytes) → bool ok to copy the GPU side content from the current LuaVBO to another.
add mouse2 to mouse10 “keys” for mousebuttons that can be bound, ditto sc_mouse2-10 scancodes. LMB (mouse1/sc_mouse1) is planned to be made bindable later.
rmlUI textures use nearest pixel filtering instead of linear. The intended effect is crisper text with anti-aliasing.
add GL stencil ops Lua constants (KEEP, INCR, DECR, INCR_WRAP, DECR_WRAP, in addition to the already-existing ZERO, INVERT, REPLACE).
added DWMFlush numerical springsetting, for Windows only. Forces Windows Desktop Compositors DWMFlush before each SDL_GL_SwapWindow, preventing dropped frames (use nVidias FrameView to validate dropped frames, or BARs Jitter Timer widget). Value of 1 does DWMFlush before SwapBuffers, value of 2 does DWMFlush after swapbuffers.
enabling dev mode (either via startscript or at runtime) adds debug.* functions to synced Lua.
/smoothmesh renderer stays enabled even if you disable cheats.
trying to set a deprecated/nonexistent springsetting via Lua now produces a warning.
/give now gives a correct hint for @x,y,z usage.
Spring.GetTeamList(allyTeamID?) no longer crashes if it receives 2+ args (but still ignores them, you can’t get the combined team list of multiple allyteams).
added GL.TEXTURE_2D_ARRAY Lua constant.
Spring.SetProjectileTarget now errors on invalid args.
archive cache version 20 → 21.

Fixes

fix the “no sound when removing bluetooth headphones” issue.
fix texture overrides for tex1 and tex2 for GLTF models not being read from *.gltf.lua metafile.
maybe fixed a rare bug of using an incorrect parser for model assets.
fix incorrect number of CPUs being detected on Linux with offline CPUs.
fix a crash when more than 2048 unit defs exist.
fix units who expected to path entirely within an exit-only zone but exited it getting confused.
probably fix an icons rendering related crash.
fix Spring.GetMapStartPositions returning teamIDs offset by 1.
fixed crashing aircraft sometimes bouncing off the ground without dying.
disabling cheats no longer disables debug airmesh view.
fix RmlUi crash when reloading stylesheets with documents containing scripts in head section.
fix some graphical interfaces producing harmless warnings/errors on headless builds.
fix some RmlUI crashes.
fix some remaining performance issues with fonts.
fix some pathing/QTPFS issues.
fix some jitter on Windows in mostly-idle and/or low speed multiplayer games.
fix some issues with models rendering at world origin before game start.