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06BattleCalc

Damage calculator. 12 affinities x 5 crit tiers.

ATK x DEF x Affinity x Crit = Damage. 12-element affinity system with 2x/0.5x modifiers. 5 crit tiers with 5-50% chance. O(1) per hit.

Atoms
12 affinities
Latency
~1,500ns
Size
5 KB
Use Cases
Turn-based RPGs, action RPGs, card games, auto-battlers, tower defense
Download .py

Output

Click "Run Demo" to execute in your browser (Python runs via Pyodide)...

How It Works

How BattleCalc Works

The lattice is a Python dict. Lookup is a hash table operation. Input keys, output values. That's the entire pattern.

Integrating With Your Engine

Unity: Call from C# via the embedded Python interpreter, or export the lattice to JSON and load it with JsonUtility.

Unreal: Use the Python plugin, or convert the Python dict to a TMap in C++.

Godot: GDScript can import Python directly, or use JSON.parse_string on the exported lattice.

Web/WASM: Pyodide runs the Python file directly in the browser. This demo page demonstrates that approach.

Extending the App

Add new entries to the lattice dictionary. The lookup function is generic: it takes any key and returns the corresponding value, or a default. The more entries you add, the more coverage you get. Performance stays O(1) regardless of size.

Key Insight

Every game logic problem that's hard-coded with if/else chains is actually a lookup table in disguise. (state, event) -> action is the universal pattern. The lattice just makes that pattern explicit and O(1).

Source Code

#!/usr/bin/env python3
"""
BattleCalc: Damage calculator.
Attack x Defense x Affinity x Crit = Damage. O(1) per hit.

No dependencies. Pure Python.
"""
import time
import random

# === THE LATTICE: damage matrix ===
AFFINITY = {
    "fire":      {"strong": ["nature", "ice"],      "weak": ["water", "earth"],     "neutral": ["lightning", "holy", "dark", "arcane", "physical"]},
    "ice":       {"strong": ["nature", "fire"],     "weak": ["fire", "lightning"],  "neutral": ["water", "earth", "holy", "dark", "arcane", "physical"]},
    "lightning": {"strong": ["water", "earth"],     "weak": ["earth", "lightning"], "neutral": ["fire", "ice", "holy", "dark", "arcane", "physical"]},
    "holy":      {"strong": ["dark", "shadow"],     "weak": ["dark", "arcane"],     "neutral": ["fire", "ice", "water", "earth", "lightning", "physical"]},
    "dark":      {"strong": ["holy", "arcane"],     "weak": ["holy", "light"],      "neutral": ["fire", "ice", "water", "earth", "lightning", "physical"]},
    "earth":     {"strong": ["lightning", "ice"],   "weak": ["water", "wind"],      "neutral": ["fire", "holy", "dark", "arcane", "physical"]},
    "water":     {"strong": ["fire", "earth"],      "weak": ["lightning", "ice"],   "neutral": ["holy", "dark", "arcane", "physical"]},
    "wind":      {"strong": ["earth", "lightning"], "weak": ["ice", "earth"],       "neutral": ["fire", "holy", "dark", "arcane", "physical"]},
    "nature":    {"strong": ["water", "earth"],     "weak": ["fire", "ice"],        "neutral": ["lightning", "holy", "dark", "arcane", "physical"]},
    "arcane":    {"strong": ["holy", "dark"],       "weak": ["dark", "physical"],   "neutral": ["fire", "ice", "water", "earth", "lightning"]},
    "shadow":    {"strong": ["holy", "light"],      "weak": ["holy", "light"],      "neutral": ["fire", "ice", "water", "earth", "lightning", "physical"]},
    "physical":  {"strong": ["arcane"],             "weak": ["arcane"],             "neutral": ["fire", "ice", "water", "earth", "lightning", "holy", "dark"]}
}

CRIT_TIERS = {
    "common":    {"chance": 0.05, "mult": 1.5},
    "uncommon":  {"chance": 0.10, "mult": 2.0},
    "rare":      {"chance": 0.20, "mult": 2.5},
    "epic":      {"chance": 0.30, "mult": 3.0},
    "legendary": {"chance": 0.50, "mult": 4.0}
}

def affinity_modifier(attacker: str, defender: str) -> float:
    """O(1) affinity modifier lookup."""
    if attacker not in AFFINITY:
        return 1.0
    if defender in AFFINITY[attacker]["strong"]:
        return 2.0
    if defender in AFFINITY[attacker]["weak"]:
        return 0.5
    return 1.0

def calc_damage(attacker_atk: int, defender_def: int, attacker_aff: str, defender_aff: str, crit_tier: str = "common") -> dict:
    """O(1) damage calculation."""
    base = max(1, attacker_atk - defender_def // 2)
    aff_mod = affinity_modifier(attacker_aff, defender_aff)
    crit_data = CRIT_TIERS.get(crit_tier, CRIT_TIERS["common"])
    crit_roll = random.random()
    is_crit = crit_roll < crit_data["chance"]
    crit_mult = crit_data["mult"] if is_crit else 1.0
    final = int(base * aff_mod * crit_mult)

    return {
        "base": base,
        "affinity_modifier": aff_mod,
        "is_crit": is_crit,
        "crit_mult": crit_mult,
        "final": max(1, final),
        "effect": "CRITICAL HIT!" if is_crit else None
    }

def describe_affinity(attacker: str, defender: str) -> str:
    """O(1) affinity matchup description."""
    mod = affinity_modifier(attacker, defender)
    if mod == 2.0:
        return f"{attacker.upper()} is SUPER EFFECTIVE against {defender}!"
    if mod == 0.5:
        return f"{attacker.upper()} is WEAK against {defender}."
    return f"{attacker.upper()} is neutral against {defender}."

# === DEMO ===
def demo():
    print("=" * 50)
    print("  BattleCalc: Damage calculator, O(1) per hit")
    print("=" * 50)
    print()
    print("  Combat scenario: Hero vs Dragon")
    print("  Hero: ATK 50, AFF fire, Sword (epic crit)")
    print("  Dragon: DEF 30, AFF ice")
    print()

    scenarios = [
        ("fire", "ice", 2.0, "super effective"),
        ("fire", "water", 0.5, "resisted"),
        ("fire", "fire", 1.0, "neutral"),
        ("holy", "dark", 2.0, "super effective"),
        ("dark", "holy", 0.5, "resisted"),
        ("ice", "fire", 0.5, "resisted"),
        ("lightning", "water", 2.0, "super effective"),
        ("shadow", "holy", 0.5, "resisted")
    ]

    for aff_a, aff_d, expected, desc in scenarios:
        start = time.perf_counter_ns()
        mod = affinity_modifier(aff_a, aff_d)
        elapsed = time.perf_counter_ns() - start

        result = "OK" if mod == expected else "MISMATCH"
        print(f"  {aff_a:10s} vs {aff_d:10s} = x{mod}  ({desc:15s}) [{elapsed}ns] [{result}]")

    print()
    print("  Battle rounds:")
    print()
    for i in range(8):
        start = time.perf_counter_ns()
        result = calc_damage(attacker_atk=50, defender_def=30, attacker_aff="fire", defender_aff="ice", crit_tier="epic")
        elapsed = time.perf_counter_ns() - start
        crit_str = " [CRIT!]" if result["is_crit"] else ""
        print(f"  Round {i+1}: {result['final']:4d} damage{crit_str}  (base:{result['base']} x{result['affinity_modifier']} x{result['crit_mult']}) [{elapsed}ns]")

    print()
    print("=" * 50)
    print("  12 affinities, 5 crit tiers. O(1) per hit. No formulas.")
    print("=" * 50)

if __name__ == "__main__":
    demo()