Fix #1698, reverting units to nanoframe via Lua

[sprunk]

No description provided.

[saurtron]

Tested and seems to work fine (although maybe not completely, see below comments), although not sure if it can be missing something, as some of the operations at FinishedBuilding don't seem to be reversed, for example ChangeLos or envResHandler callins, also doesn't have an eoh, while other callins usually have it when changing unit status.

Just for the record, don't think it's a blocker since any shortcomings will likely come up with usage.

[saurtron]

Something else I noticed, if I don't call SlowUpdate() at the beginning of the function (just after the beingBuilt check) then weird things happen like not all units render properly but may have map icon (could be because I create and revert to nanoframe very fast (4 frames), if I wait more (20) frames before revert then it works ok).

left is with slowupdate call, right without (otherwise it's the same scenario):

[sprunk]

ChangeLos

Seems so. On some level this is good because games would be able to keep nanoframes able to see, but it looks like nanoframes don't have LoS anyway:

spring/rts/Sim/Misc/LosHandler.cpp

Lines 173 to 174 in 5dd2266

	if (unit->isDead || unit->beingBuilt)
	return;

envResHandler

Good find. This (and all other feedback here) applies to the existing method of reverting units to nanoframes via reclaim so should be fixed at some point even if this PR doesn't go through. #1883

eoh

Eoh looks inconsistently applied, some callins have it and some don't. It didn't have it previously so I kept it as-is, it would probably be fine to have since the event is relatively rare but impactful.

not all units render properly

BAR has custom rendering which probably assumes units can't revert to nanoframes so this is somewhat expected. Native engine nanoframe drawing works.

[saurtron]

BAR has custom rendering which probably assumes units can't revert to nanoframes so this is somewhat expected. Native engine nanoframe drawing works.

I'm not convinced, I did add support for ReverseUnitBuilt so wireframe rendering of reverted units would work properly.

Also I did test without cus_gl4 (I think it's the one doing the custom rendering, as wireframe shows normal without that). Also tried forcing dependency test to return false for gl4, that forces even more custom rendering wupgets to be disabled.

Here shows the same problem with default wireframe drawing (that's a 10x10 solar array, but some don't show without the slowupdate call):

In case you want to take a look I uploaded my changes to test this here, added UnitReverseBuilt support for cus_gl4, gl4_unit_tracker and widget, also added a test test_wireframe so can be tested with /runtests wireframe with bar. All included at that branch, where cus_gl4 is disabled too.

The problem might be triggered by the amount of units and very fast reverting to wireframe since unit creation, rather than custom rendering. Not totally sure about this but looks worth investigating.

Not saying it's not a bar specific issue, but it might not be.