Gameplay Engineering Guardrails

1. Tick Rate Integrity (0.4s Standard)

Rule: The global game tick is 0.4 seconds (400ms). This is a hard deviation from the 0.6s OSRS standard.

• Constants: Use a centralized TICK_DURATION constant (e.g., in shared-logic).
• Time Conversion:
  • 1 Tick = 0.4s
  • 10 Ticks = 4.0s (not 6.0s)
  • 100 Ticks = 40.0s (Legacy minute is 100 ticks = 60s @ 0.6s. We are faster).
• Animation Sync: Ensure animation clips match the 0.4s multiple. (e.g. Attack animation should be 0.8s, 1.2s, not 0.6s).
• Regeneration: Adjust Health/Dharma regeneration rates to match the faster pace (or keep absolute time equivalent by reducing per-tick amount).

2. Combat Formulas & Determinism

Rule: Combat logic must be deterministic.

• Integer Math: Use integer math for all damage calculation steps. Drop remainders (floor) only where specified in the design.
• RNG Isolation: Use a seeded or controllable RNG for combat rolls to allow unit testing of specific hit scenarios.
• Stance Modifiers:
  • Offensive: +3 Visible Strength/Attack
  • Defensive: +3 Visible Defense
  • Balanced: +1 to all
• Testing: All formulas must have unit tests covering Min/Max/Average cases.

3. Leveling & Experience

• Level Cap: 100 (approx 18M XP).
• Data Types:
  • Experience: u32 (assuming 1 XP = 1 unit) or u64 (if 1 XP = 10 units). Verify existing schema.
  • Max XP: 200,000,000 (200M).
• Overflow Protection: Ensure current_xp + gain does not overflow. Cap at 200M.

4. Inventory System

• Grid Size: Base 30 slots (6x5).
• Expansion: Logic must support dynamic sizing up to 50 slots.
• Serialization: Ensure save formats handle variable inventory sizes gracefully.

5. Vedic Theme Enforcement (Asset & Data)

• Strict Ban: No "Mithril", "Adamant", "Rune".
• Replacements:
  • Mithril -> Soma
  • Adamant -> Meteoric
  • Rune -> Divya
• Gods: No Saradomin/Zamorak/Guthix. Use Agni/Yama/Indra/Varuna capabilities.

6. Performance

• Entity Counts: Combat loop must support 2000+ active entities. Use ParallelSystemDescriptor in Bevy or appropriate ECS batching.
• Broadphase: Use spatial hashing for entity targeting queries.