Runtime
The runtime attaches to KH2 Final Mix PC (Steam Global) and bridges its injected DLL to a co-op session. Each machine controls its own primary actor; remote players arrive through AvatarBridge as puppets, while WorldBridge carries host-native enemy, room and progress traffic. Network integration is active.
Components
| Component | Purpose |
|---|---|
IGameBridge.hpp, GameBridgePC.hpp/cpp | Process attachment, memory access and native actor discovery |
CameraController.hpp | Optional external camera override and restoration |
ReplicaController.hpp | Legacy actor snapshot application, opt-in |
KH2Offsets.hpp | Steam Global memory offsets and their qualification |
RuntimeMain.cpp | Config, network admission, avatar/world pumps, diagnostics and shutdown |
Source compatibility is protocol 34, AvatarBridge 4, WorldBridge 13 and CaptureChannel 1. Build the runtime, DLL, relay and control tools together; restart the owned game to pick up a newly built DLL. See setup and the development workflow.
Running
For player sessions use the friend launcher, which handles owned launch/injection, account confirmation and player defaults. The standalone runtime defaults to offline, camera override on and a 16 ms loop:
.\build\Release\kh2coop_runtime_scaffold.exe --pid 1234 --role player --config kh2coop_runtime.ini --no-camera
Use an actual owned PID in place of 1234. Arguments override INI values.
| Option | Purpose |
|---|---|
--pid <pid> | Select the intended game process |
--role player|friend1|friend2 | Canonical network slot (0|1|2 also accepted) |
--mode campaign_coop|public_realm | Campaign is the supported development focus; public realm is planned scaffolding |
--network --server <host> --port <port> | Enable ENet; default runtime endpoint is 127.0.0.1:7946 |
--peer-id <id> | Unique peer label |
--content <hash> | Content handshake identifier; game/mod labels come from INI |
--steam-host --steam-allow <ID64> | Host through the owned game's Steam broker; allow up to two friends |
--steam-join <ID64> | Join an allowlisting host as a friend slot |
--no-network | Offline mode |
--no-camera | Disable external camera override at startup |
--tick-ms <ms>, --max-ticks <n> | Loop delay and bounded runtime lifetime |
--log-actor-state | Periodic actor diagnostics |
--desync-dir <path>, --inject-log <path> | Diagnostic spool and exact registered inject log |
--link-latency-ms <n>, --link-jitter-ms <n>, --link-loss <pct> | Test link impairment |
--legacy-replica | Opt into the old snapshot/input path |
Steam requires explicit --pid, a broker-enabled owned game and the appropriate
role. It uses Valve relays without the standalone ENet server. Prefer the launcher
for account, allowlist and missing-app-ID-file consent handling. --help lists
the complete runtime interface, including listener diagnostics.
The ENet relay defaults to port 7782, unlike the runtime's 7946. Set an explicit matching port and game/content/mod identifiers. Admission rejects incompatible protocol, build, content, mode or slot requests. A verified roster does not by itself establish native world convergence.
F8 toggles the optional camera override on Windows. Direct developer launches
retain their native feature defaults; the friend launcher enables its player
profile, including Normal difficulty, downed/revive and enemy mirroring. See
the plan for scope.
The legacy InjectOwnedInput() and ApplyReplicaEnemyState() stubs are not the
current injected avatar/world gameplay path.
Interpolation delay
The qualified defaults are avatar 80 ms and enemy cursor 6 host frames.
Set KH2COOP_AVATAR_RENDER_DELAY_MS on each runtime (integer 1..500), and
KH2COOP_ENEMY_CURSOR_DELAY_FRAMES on each game/DLL (integer 4..18), before
launch. Invalid values fall back to defaults and log source=invalid-default;
accepted overrides log source=env. The enemy lower bound preserves the existing
+/-3-frame cursor hysteresis. Hold/release thresholds and packet cadence are unchanged.
KH2COOP_LATENCY_TRACE=1 enables bounded diagnostic counters (18,000 records/
frames); it does not gate gameplay. Qualified loopback comparisons and their
limits are retained in the latency results.