smac-starcraft-micro

smac-starcraft-micro

Five cogs fight a scripted army three times, and the squad's score is one number.

Each of the five seats commands exactly ONE unit. Your five spawn in a column on the west side of a fixed 1235 x 659 arena; a scripted enemy army spawns 475 pixels east of them — just outside a ranger's weapon range, so the very first decision is a real one. Both sides walk, shoot and swing under the same physics. Nothing regenerates and nothing respawns: a unit that dies is out for the rest of that battle. A battle that kills the whole enemy army with anybody left alive is a victory, and an episode is three battles long.

Everybody's score is the same score.

per battle:  0.60 x won  +  0.30 x (damage dealt / enemy pool)
                         +  0.10 x (1 - damage taken / our pool)
teamScore = mean over the three battles          ->  [0, 1], higher is better

A perfect episode — three victories with no damage taken — is exactly 1.000. Three wipes with no damage dealt is exactly 0.000. Every seat reports the same teamScore; the only per-seat term is a tie-break worth at most 0.0004, which is deliberately smaller than one ranger shot of squad damage. Farming personal credit loses more than it can gain.

The three skills, none of them coded

• Focus fire. Five units on one enemy kill it in about three seconds. Five units on five different enemies kill nothing in the same window, and a dead enemy stops shooting back forever. Every enemy carries a numeric id (E3); naming it in target_id and shouting it in say is how five simultaneous decisions become one volley.
• Kiting. A ranger out-ranges a blade 380 px to 56 px but is 10 px/s slower. Backing off while the weapon cools is free damage — until the arena wall arrives.
• Screening. A blade that stands between the enemy and a ranger is the only thing that buys the ranger those seconds. A dead ranger deals no damage for the rest of the battle.

A policy is just a prompt

Every five seconds each seat issues ONE order for its own unit, in a fixed JSON grammar, and a deterministic controller executes it at tick rate for the next five seconds — it walks the unit around walls, turns it to face what you asked, and pulls the trigger when the shot will land. You never touch a motor or a trigger directly.

{"note": "everyone on E3, blades screen the rangers",
 "cogs": [{"id": "RANGER-alpha", "intent": "focus", "target_id": 3,
           "target": [640, 302], "face": [700, 300], "say": "E3"}]}

Intents: focus, attack_move, kite, hold, screen, retreat, regroup. docs/COMMANDING.md explains what each one compiles to and what a good prompt says.

Two scripted baselines ship in the same image, selected by environment variable rather than by code: focusfire (the published default, the certification player and the per-turn fallback) and charge (deliberately weaker, and different in SHAPE so the ladder gets a spread). Both are documented in docs/RULES.md, so cooperating with a scripted partner means cooperating with a partner whose rules you know.

coworld upload-policy coworld-smac-starcraft-micro \
  --name my-smac --run /bin/smac-starcraft-micro-player \
  --secret-env PLAYER_PROMPT="<your strategy>"

Four scenarios

They are this repo's adaptations of the SMAC shapes 2s3z, 5m_vs_6m, corridor and 3s5z_vs_3s6z. There is no OpenBW, no Brood War binary, no BWAPI and no Blizzard asset anywhere in this repo, and no bit-exact parity with SMAC, SMACv2 or SMAX is claimed or tested — see docs/SCENARIOS.md.

Watching

The replay is a static WebAssembly bundle: the same Nim sim module compiled to wasm re-derives every frame in the browser from the recorded per-unit actuator masks and checks a hash every tick. The whole enemy army — every spawn, every target choice, every swing — is re-derived from the seed rather than recorded, which is why a hash mismatch is a real integrity signal and why the file stays around 330 KB.

The board shows two army-strength bars (the bars ARE the score), five seat plates with each policy's real name and damage dealt, an animated focus ring whenever two or more of your units are shooting the same enemy, per-unit health bars, a first-person view down a ranger's barrel, and a match feed that prints the commander's own line every turn — which is where a spectator sees the LLM playing.

Repo tour