bugfix: China Artillery shells can no longer destroy each other

[Stubbjax]

Summary

This change prevents the shells fired by China's Artillery Barrage special power from destroying each other, which would lead to variable damage yields and unpredictable outcomes.

Damage is now always identical (and up to 20% higher) as a result, with only the individual locations of each shell impact being random. This fix reduces the likelihood of scenarios where 1 or 2 Oil Derricks survive a level 3 Artillery Barrage.

Details

Shell impact distribution is random (as defined by the WeaponErrorRadius field in the barrage OCLs) and does not follow any predefined ScatterTarget coordinates like the SCUD Storm or Rocket Pods weapons. This means that it is possible for the strike to do significantly less damage depending on how many shells simultaneously strike the same location.

The average shell loss varies with each level, and increases as more shells are fired. Damage output was measured 15 times at each level before the fix and 3 times at each level after the fix. Actual damage always equals max damage after the fix. This is represented in the table below.

Level	Shells Fired	Max Damage	Shell Loss	Actual Damage	Percentage Loss
1	12	1,260	0 - 1	1,155 - 1,260	0% - 8%
2	24	2,520	0 - 2	2,310 - 2,520	0% - 8%
3	36	3,780	0 - 7	3,045 - 3,780	0% - 20%

Rationale

Ideally the better player wins a match through superior strategy and execution. Uncontrolled random elements prevent players from reliably calculating risk and reward, and can arbitrarily reward mistakes or punish optimal play, making outcomes feel unearned.

A player's Oil Derricks randomly surviving on Defcon 6 can be the difference between winning and losing. It is unsatisfying if match outcomes hinge on luck.

Testing

Before

Oil Derricks often survive from a level 3 Artillery Barrage on Defcon 6

BEFORE.mp4

After

Oil Derricks are less likely to survive a level 3 Artillery Barrage on Defcon 6

AFTER.mp4

[xezon]

Fix missing for Generals.

[xezon]

INI doc would have been nice.

[Stubbjax]

INI doc would have been nice.

I have added substantial doc to the PR description.

[xezon]

Is substantial indeed. Percentage loss does not properly correlate with the damage value ranges.