Port missions to the new Lua API

[Mailaender]

The new https://github.com/OpenRA/OpenRA/wiki/Lua-API has landed in #5190. Time to update the maps and enhance the standard library. Some shared deficiencies of both old and new Lua API:

• Cell triggers #4400 Missing cell triggers
• Expose objectives panel to lua #4541 Lua integration of objectives panel

Red Alert

Mission	Basis	Assignee	PR	Status
allies-01-classic	old Lua	@Mailaender	#6377	done
allies-02-classic	old Lua	@Mailaender	#6379	done
allies01	legacy C#			redundant
allies02 (co-op)	legacy C#	@obrakmann	#11316	done
allies03 (co-op)	legacy C#	@Mailaender	#11679	done
allies04 (co-op)	legacy C#	@Mailaender	#11702	done
desert-shellmap	old Lua	@pchote	#5190	done
fort-lonestar	legacy C#	@Mailaender	#5469	done
intervention	old Lua	@obrakmann	#6762	done
monster-tank-madness	legacy C#	@abcdefg30	#6552	done
soviet01-classic	legacy C#	@Mailaender	#6796	done
survival01	legacy C#	@abcdefg30	#6934	done
survival02	legacy C#	@abcdefg30	#7164	done

Tiberian Dawn

Mission	Basis	Assignee	PR	Status
gdi01	old Lua	@Mailaender	#5782	done
gdi02	old Lua	@obrakmann	#6324	done
gdi03	old Lua	@Mailaender	#6795	done
gdi04a	old Lua	@obrakmann	#6762	done
gdi04b	old Lua	@obrakmann	#6762	done
gdi04c	old Lua	@obrakmann	#6325	done
nod01	old Lua	@obrakmann	#6326	done
nod03a	old Lua	@obrakmann	#6327	done
nod03b	old Lua	@obrakmann	#6328	done
shellmap	old Lua	@pchote	#5190	done

[obrakmann]

@pchote said some time ago on IRC that he didn't want to the lua lib to be ported 1:1. It sounded like he already had an idea of what it should look like. @pchote, can you please give a quick outline of what you had in mind?

[obrakmann]

I added the Allies02 (non-classic) mission to the list. It was a two-player coop mission that looked quite nice, and people have been asking if coop missions were possible.

[Mailaender]

I also suggest that we give @ScottNZ's custom made allies02-04 a better/less-confusing name and remove the -classic suffix from the original campaign maps to bring them in line with the Tiberium Dawn mod. I also liked the improvements in allies01 with a bigger map, more enemies, the new oil derricks and controllable cruisers.

[abcdefg30]

Could somebody assign me to "monster-tank-madness", please?

[Mailaender]

Done.

[Mailaender]

See https://github.com/OpenRA/OpenRA/blob/1d9681a1d2769a9c736b79ba612204b979bf9d13/OpenRA.Mods.RA/Missions/MonsterTankMadnessScript.cs for the last revision before removal.

[pchote]

I think it's important that we define a list set of rules and changes for the mission ports that we can then apply uniformly. I found it very frustrating to waste an engineer in the new Allies03 port because I didn't realize that it would sabotage instead of externally capture. It also feels a bit weird to disable the fog of war in TD, but not in RA.

Some potentially tricky issues are:

• Fog of war (are there any missions that become unreasonably difficult if you can't see areas you have explored?)
• Multiple building queues in TD throwing off the balance.
• Externally capturing engineers in RA.
• Changes in the tech trees and unit functionality (e.g. thief -> hijacker, SSM launcher -> SAM launcher).
• Changes in difficulty because of our balance changes (e.g. GDI04c)
• Secondary objectives: we should add them where they make sense, but some of the existing ones feel forced.

IMO our goal should be to make these missions feel natural within our new gameplay. This means that we will need to make some changes to work around changes and inconsistencies, but we certainly should not make changes motivated by lazyness ("it's too much work to script X to match the original, and we have already changed Y and Z so it's ok" is a cop out).

On the other hand, I think that applying a blanket "absolutely no changes from our MP units" would be a bad idea. Squad-based missions were a big part of the original games, and our MP rules for e.g. tanya/commando and aircraft auto-takeoff ruin this feel.

Again IMO, here's some initial thoughts towards some conversion guidelines:

• Enable the fog of war for all missions.
• Add scripted entry sequences instead of starting with a block of units on the map.
• Adjust RA missions to use external engineers and thief -> spy.
• Disable auto-attack for commando/tanya missions.
• Disable unit bounties in RA (especially the squad based missions).
• Test, Test, Test... and then adjust the enemy unit placement to address any balance issues.

[obrakmann]

I agree in principle, even though I'd solve some things differently. I really dislike external captures, for one.
Edit: I also don't quite understand your obsession with replacing pre-placed units with reinforcements.

Just one comment, though:

Fog of war (are there any missions that become unreasonably difficult if you can't see areas you have explored?)

Off the top of my head, gdi06 comes to mind, where you control a commando and have to avoid a patrol of buggies that passes by in regular intervals. If you can't see when the patrol passes, it becomes trial and error (error = instant death).

[pchote]

I really dislike external captures, for one.

Me too, but I think it is more important to not have units work completely different between the two modes. I would be quite happy to see both SP and MP engineers shift back to normal capturing.

Off the top of my head, gdi06 comes to mind

We could solve cases like this with a scripted camera at a key place, possibly tied in with a secondary objective.

[cjshmyr]

I would be quite happy to see both SP and MP engineers shift back to normal capturing.

Wouldn't oppose this

[phrohdoh]

If by normal capturing we mean entering/consumed; 👍

[obrakmann]

Another rule I'd like to see enforced: disable viceroids in TD missions.

[Mailaender]

Enable the fog of war for all missions.

Somehow the original gdi01 C# hack script had fog of war disabled and I copy pasted it everywhere. This seems more like an accident. 👍 for fixing that everywhere.

[Mailaender]

We can add @ScottNZ's take on allies-01 as an additional difficulty like @abcdefg30 did in #8359.

[obrakmann]

We're finally done with this \o/. Only took more than two years ;)

[abcdefg30]

🎉 🎉 Good job everyone.