Formations - units stop their current order to get into formation

[elexis]

Problem 1: Units cancel their current order Problem 2: Units move away from the actual target Problem 3: Units might not execute the build order at all

1 and 2 cost valuable time, which can decide the outcome of a battle.

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Reproduce (building structures): 1. Move two units far apart 2. Start building something with one unit 3. Select both units and order them to build

Expected Result: The unit close to the structure doesn't stop building. The other unit walks to that structure and builds it. After that they can form.

Actual Result: When the other unit arrives at the structure, the constructing unit stops, moves away from the structure (towards the other unit) and enters the formation. If the units were not far apart, they walk to the building and construct it. However if they were, they will just stop after getting into formation and never start building at all.

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Reproduce (attacking enemies): 1. Have some units attacking a building 2. Select those and some other units far away 3. Order them to attack the same building

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Same applies to gathering resources and possibly other orders.

[elexis]

An illustration how the behavior costs valuable time.

[elexis]

An illustration of how the units don't execute the order to build the house.

[elexis]

Seen on a18 - the units stop their attack to get into formation but don't continue the attack. (Same bug as above)

[wraitii]

Isn't this a duplicate of #1791?

[elexis]

Replying to wraitii:

Isn't this a duplicate of #1791?

Could be.

The first gif shows units on aggressive stance, the second one on passive stance if I remember correctly.

If we want to reintroduce formations enabled by default in a20, this has to be fixed before that.

[elexis]

Backlogging due to lack of progress.

[Imarok]

Move tickets to Simulation as UI & Simulation got some sub components.

[wraitii]

Does seem to be a duplicate of #1791, but this seems slightly better specced.

This only happens with a default formation. TBH, I'm not sure it needs to be fixed in general - orders like "gather" don't really make sense for formations, and it seems like that's the flaw in the first place.

Maybe only "walk" and related orders should have a default formation, and the others default too null.

[Freagarach]

Single units goes fine, but when performing the test plan with two formations the reported misbehaviour is observed. (SVN r23782.)

[wraitii]

In 24480:

Allow picking a default formation for walk (and walk-like) orders.

This allows choosing a "default formation", which is activated automatically for units given walk orders (and attack-walk etc.).
Conversely, units in formation that are given a gather/build/... order are taken out of formation and given the order individually.
The default formation can be selected by right-clicking on any formation icon.

This leverages formations for walking, where they are quite efficient (in fact, perhaps too efficient), while circumventing issues with various orders.

Choosing the "null formation" as the default formation de-activates the behaviour entirely, and plays out exactly like SVN.

This makes it possible to queue a formation-order then a noformation-order (i.e. walk then repair), though the behaviour isn't very flexible.

For modders, it should be relatively easy to change the setup for each order, and/or to force deactivating/activating formations in general.

Tested by: Freagarach, Angen

Refs #3479, #1791.
Makes #3478 mostly invalid.

Differential Revision: ​https://code.wildfiregames.com/D2764

[wraitii]

Going to close this as a duplicate of #1791, which it mostly is.