From d995942b4f933a65c9fef3b6751907b6e37ae060 Mon Sep 17 00:00:00 2001 From: Eevee Date: Sat, 27 Mar 2010 19:47:36 -0700 Subject: [PATCH] Remove absolute HP from the capture chance formula. --- pokedex/formulae.py | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/pokedex/formulae.py b/pokedex/formulae.py index 5ee16c4..29ab514 100644 --- a/pokedex/formulae.py +++ b/pokedex/formulae.py @@ -44,9 +44,10 @@ def earned_exp(base_exp, level): return base_exp * level // 7 -def capture_chance(current_hp, max_hp, capture_rate, +def capture_chance(percent_hp, capture_rate, ball_bonus=1, status_bonus=1, heavy_modifier=0): - """Calculates the chance that a Pokémon will be caught. + """Calculates the chance that a Pokémon will be caught, given its capture + rate and the percentage of HP it has remaining. Returns five values: the chance of a capture, then the chance of the ball shaking three, two, one, or zero times. Each of these is a float such that @@ -63,9 +64,15 @@ def capture_chance(current_hp, max_hp, capture_rate, # ROOTS in a moment, so it can't possibly be. It probably doesn't matter # either way, so whatever; use regular ol' division. ball_bonus and # status_bonus can be 1.5, anyway. - base_chance = ((3 * max_hp - 2 * current_hp) * capture_rate * ball_bonus) \ - / (3 * max_hp) \ - * status_bonus + + # A slight math note: + # The formula is originally: (3 max - 2 curr) rate bonus / (3 max) + # I have reduced this to: (1 - 2/3 * pct) rate bonus + # My rationale is that this cannot possibly be integer math, so rounding is + # not a problem and commutation won't make a difference. It also + # simplifies the input considerably. + base_chance = (1 - 2/3 * percent_hp) * capture_rate \ + * ball_bonus * status_bonus shake_index = (base_chance / 255) ** 0.25 * (2**16 - 1)