Bad Day Simulator

A 3D physics sandbox. You get a level, you place puppets and objects with their own behaviours and interactions, and the puppets have a bad day. They feel what happens to them, flinch, writhe, and sometimes crawl on toward whatever they wanted, because they are driven by Lodur.

Status: first slice only (the pain box). The 3D sandbox does not exist yet. The design is Lodur's target, docs/lodur-target.md in the Lodur repo; this game is its first consumer and its proving ground.

Why it exists

It shows and tests everything Lodur does (stimuli, reflexes, pain and shock, impairment) in one place where a player can poke at all of it.

Where it lives

Canonical: https://eureka.gamecult.org/forge/GameCult/BadDaySimulator. GitHub GameCult/BadDaySimulator is a push mirror.

What runs today: the pain box

A headless, deterministic simulation of one virtual human with a hand in a pain box. Question it answers: how long until the will breaks, or the box is disabled first? Entry points:

• src/BadDay.Core/PainBoxSimulation.cs: the model and the tick loop.
• src/BadDay.Core/PainBoxParameters.cs: every tunable, with defaults.
• src/BadDay.Core/Sweep.cs: consecutive seeds, break-time min/median/max.
• src/BadDay.Cli: baddaysim.
• tests/BadDay.Tests: determinism, break-time and monotonicity tests.

dotnet run --project src/BadDay.Cli -- run   --seed 1
dotnet run --project src/BadDay.Cli -- sweep --seed 1 --count 50 --pull 0.3
dotnet run --project src/BadDay.Cli -- run   --seed 1 --disable-at 5
dotnet run --project tests/BadDay.Tests          # exits non-zero on failure

run prints a timeline (samples every second, plus flinch, break and withdrawal events) and a one-line summary. Options: --intensity, --pull, --disable-at, --max, --every.

Modeled

Fixed 10 ms tick, seeded SplitMix64 (the only randomness; integer arithmetic, so a seed means the same stream anywhere). Following the layers in Lodur's target, flattened to one loop:

• Perception / nerve: the box emits an intensity (ramped in, with seeded jitter). A nociceptor applies a threshold and sensitises under sustained stimulus; the signal reaches the centre after a conduction delay.
• Reflex: the arriving signal drives a withdrawal reflex. Will suppresses it in proportion to resolve; what leaks through is a flinch, and holding it down accumulates strain (suppression is never free, per reflex-gain-from-drive).
• Drive: pain rises with the signal and decays; resolve drains with pain and strain, scaled by (1 - ObjectivePull), and recovers only when pain is low. Two seeded traits (nociceptor gain, resolve drain) make each seed a different person.
• Goals: HoldHand (the objective, with its pull) and Withdraw. When resolve reaches zero the goal flips and the hand is out after the withdrawal latency (100 ms).
• Measure: TimeToBreakMs (resolve hits zero) and the outcome: WillBroke, BoxDisabled (disabled while the will held), or Endured.

Not modeled

No body, physics, balance, joints or ragdoll; no shock, adrenaline or blood loss; no impairment or crawling; no Unity binding; no puppets or objects other than the box; no learning. The reflex never removes the hand by itself: only a broken will does. All parameter values are placeholders, not physiology; the figures in Lodur's target are marked unverified and so are these. Break times in the output are properties of this toy model, not predictions about people. Bit-exact output across CPU architectures is not claimed; same-machine runs are byte-identical (the loop uses only + - * / and comparisons, no transcendental functions).

Persistent content (puppet definitions, drive parameters, saved levels) will be CultCache per Lodur's content-is-cultcache; this slice has none, so it has no cache layer and no JSON.

Build note

The core has no engine reference (core-engine-free). The slice has no package dependencies, so the tests are a plain console program rather than xunit. On the Yggdrasil mind host dotnet restore currently fails on a NuGet named mutex (read-only /dev/shm); the slice was compiled there with Roslyn's csc directly, which is why the .csproj files are the unverified part.