This is the changelog since version 2590.

Caveats

These are the entries which may require special attention when migrating:

explicitly specified weapon def scarTTL value is now the actual TTL. Previously it was multiplied by the ground decals level springsetting, which defaults to 3, so if you had tweaked scars they may turn out to have significantly different TTL now.
weapons with groundBounce = true will now bounce even if numBounces is left undefined. This is because numBounces = -1, which is the default value, will now result in infinite bounces as intended instead of 0.
a bunch of changes in damage and death Lua events, see below.

Features

wupget:UnitDestroyed will pass the builder as the killer if a unit gets reclaimed. Note that reclaim still does not generate UnitDamaged events.
wupget:UnitDestroyed now receives a 7th argument, weaponDefID, with the cause of death. Widgets receive this info regardless of LoS on the attacker (no new hax, UnitDamaged already did this).
the weaponDefID above is never nil, all causes of death are attributable including things like “was being built in a factory, got cancelled” or “died automatically due to isFeature def tag”. Added a bunch of Game.envDamageTypes constants for this purpose. See the table at the bottom of the page.
the 1000000 damage that applies to units being transported in a non-releaseHeld transport when it dies for non-selfD reasons will now be attributed to the new TransportKilled damage type in UnitDamaged, previously was Killed.

add math.normalize(x1, x2, ...) → numbers xn1, xn2, .... Normalizes a vector. Can have any dimensions (pass and receive each as a separate value). Returns a zero vector if passed a zero vector.
wupget:DrawWorldPreParticles now has four boolean parameters depending on which phase is being drawn: above water, below water, reflection, refraction. They aren’t mutually exclusive.
add Spring.AllocateTable(arraySlots, hashSlots) → {}. Returns an empty table with more space allocated. Use as a microoptimisation when you have a big table which you are going to populate with a known number of elements, for example #UnitDefs.
add Spring.ForceUnitCollisionUpdate(unitID) → nil. Forces a unit to have correct collisions. Normally, collisions are updated according to the unitQuadPositionUpdateRate modrule, which may leave them unable to be hit by some weapons when moving. Call this for targets of important weapons (e.g. in script.FireWeapon if it’s hitscan) if the modrule has a value greater than 1 to ensure reliable hit detection.
pairs() now looks at the __pairs metamethod in tables, same as in Lua 5.2.

add windup weapon def tag. Delay in seconds before the first projectile of a salvo appears. Has the same mechanics as burst.

fix draw position for asymmetric models, they no longer disappear when not appropriate.
fix streaming very small sound files.
fix Spring.SetCameraTarget reverting to the old position.
the quadFieldQuadSizeInElmos modrule now only accepts powers of two instead of breaking at the edges of the map.

Game.envDamageTypes.???	Description
AircraftCrashed	Aircraft hitting the ground
Kamikaze	Unit exploding due to its kamikaze ability
SelfD	Unit exploding after a self-D command and countdown
ConstructionDecay	Abandoned nanoframe disappearing (the process itself is HP removal)
Reclaimed	Killed via reclaim (the process itself is HP removal)
TurnedIntoFeature	Unit dying on completion, without explosion, due to `isFeature` def tag
TransportKilled	Unit was in transport which had no `releaseHeld`. If the transport was not self-destructed, the unit also receives 1000000 damage of this type before dying.
FactoryKilled	Unit was being built in a factory which died. No direct way to discern how exactly the factory died currently, you’ll have to wait for the factory’s death event.
FactoryCancel	Unit was being built in a factory but the order was cancelled.
UnitScript	COB unit script ordered the unit’s death. Note that LUS has access to normal kill/damage interfaces instead.
SetNegativeHealth	A unit had less than 0 health for non-damage reasons (e.g. Lua set it so).
OutOfBounds	A unit was thrown way out of map bounds.
KilledByCheat	The `/remove` or `/destroy` commands were used.
KilledByLua	Default cause of death when using `Spring.DestroyUnit`.

KilledByLua is guaranteed to be the “last” value, so you can define your own custom damage types via e.g.

Game.envDamageTypes.CullingStrike      = Game.KilledByLua - 1
Game.envDamageTypes.SummonTimerExpired = Game.KilledByLua - 2

Written by: sprunk