Used for testing NPC resist on EQEmu

resists.py

#! /usr/bin/env python
# -*- coding: utf-8 -*-
# vim:fenc=utf-8
#
# Copyright © 2014 Michael Cook <mcook@mackal.net>
#
# GPL whatever?

# used for testing NPC's resists

import random

def resist(level, caster_level, resist, damage_spell):
    resistfalloff = 67
    # harmony spells default to 15 here
    resist_chance = 0
    resist_modifier = 0 # some spells have a mod
    target_resist = resist # this is the castee resist
    temp_level_diff = level - caster_level
    if level >= resistfalloff:
        a = resistfalloff - 1 - caster_level
        if a > 0:
            temp_level_diff = a
        else:
            temp_level_diff = 0

    if temp_level_diff < -9:
        temp_level_diff = -9

    level_mod = int(temp_level_diff * temp_level_diff / 2)

    if temp_level_diff < 0:
        level_mod = -level_mod

    if caster_level - level < -20:
        level_mod = 1000

    if damage_spell:
        level_diff = 0
        if level >= resistfalloff:
            level_diff = resistfalloff - 1 - caster_level
            if level_diff < 0:
                level_diff = 0
        else:
            level_diff = level - caster_level
        level_mod += (2 * level_diff)

    resist_chance += level_mod
    resist_chance += resist_modifier
    resist_chance += target_resist

    # min/max resist checks

    # resist roll (0, 200)

    return resist_chance

def main():
    # hardcoded stuff, change to test other settings
    resist_chance = resist(71, 65, 200, False)
    print('Resist chance: ' + str(resist_chance))
    tally = 0
    print('predicted percentage: ' + str(0.0 if resist_chance >= 200 else (200 - resist_chance) / 2.0) + '%')
    for i in range(0, 1000000):
        if random.randint(0, 200) > resist_chance:
            tally += 1

    print('total landed: ' + str(tally))
    print('observed percentage: ' + str(tally / 1000000.0 * 100) + '%')

    return 0

if __name__ == '__main__':
    main()