[Feature]: Add unit categories governing structure rotation on spawn

[lL1l1]

Describe the Feature

In the modding section on discord I have noticed many different people asking to remove structure rotation on spawn or simply finding it ugly/awkward.
There should be 2 new categories to prevent the behavior or trigger only the 90 degree rotation behavior.

Expected Behavior

Adding this category to a unit prevents it from being rotated by StructureUnit.lua code:

fa/lua/sim/units/StructureUnit.lua

Lines 64 to 67 in a6f7143

	-- Structures that rotate towards the enemy: PD, AA, Torp launchers, Artillery, and TMD (except Volcano)
	local StructureUnitOnStartBeingBuiltRotateBuildings = categories.STRUCTURE * (categories.DIRECTFIRE + categories.ANTIAIR + categories.ANTINAVY + categories.ARTILLERY + (categories.ANTIMISSILE - categories.SILO - categories.uab4201))
	-- Structures that rotate in 90 degree steps: T2/T3/T4 Artillery
	local StructureUnitRotateStaticArty = categories.ARTILLERY * (categories.TECH2 + categories.TECH3 + categories.EXPERIMENTAL) -- These always point towards map center and only rotate at 90degree steps

Screenshots

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Additional context

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🔗 Similar Issues

Related Issues

• [Bug]: Mods changing BuildOnLayerCaps no longer work #6926

👤 Suggested Assignees

• lL1l1

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