Damage Is a Pipeline

The first end-to-end piece of reTS was not a menu or a moving unit. It was a number: the exact amount of health removed when one object hits another.

That sounds modest. It turned out to be the right foundation for the whole project, because the original engine does not calculate damage in one neat formula. It passes the value through a sequence of rules, and the integer result can change if even two apparently equivalent stages are swapped.

Last verified against the project oracle: 2026-07-15.

Why order matters

The current verified path begins on the firing side, where weapon damage is adjusted by house, unit, and veterancy effects. The target then applies its armor modifiers. After that, the warhead handles distance falloff, its armor-versus table, and the global damage ceiling. Only then is the result applied to health.

Several of those stages truncate a fractional result toward zero. Multiplication is normally commutative on paper; multiplication with an integer conversion between stages is not. reTS therefore keeps the stages separate instead of collapsing them into an elegant but inaccurate expression.

The health application has its own details. Crossing half health and crossing the configurable red-health threshold are distinct events. Lethal damage is capped to the health that remained. Those transitions matter to triggers and presentation, not only to the final hit-point counter.

Healing takes a different road

Negative damage is treated as healing, but it does not simply run the normal pipeline backward. The original takes a special short-range path that skips normal distance falloff and the armor-versus table, then clamps the restored health to the unit type's maximum.

It is exactly the kind of rule a clean rewrite might “simplify” and quietly get wrong. In reTS it is explicit, tested, and visible in the result breakdown.

More than a final number

Every damage query can return the intermediate stages that produced its answer. The same functions are exercised by hand-derived examples, and the inspection surface is exposed to tools as well as normal code. That pattern—calculate, explain, and verify—became the template for every system that followed.

This first vertical is currently anchored to Yuri's Revenge behavior. The cross-version comparison for Tiberian Sun and Red Alert 2 remains separate work; the post does not assume that similar-looking combat rules are identical.