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Remove a performance optimization

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The attack prediction code used to skip creating the "A slowed" or
"B slowed" plane if A or B was already slowed. As a result, after the
battle the "summary" array of the combatant had a different meaning from
usual: normally summary[0] means the HP distribution when the combatant is
not slowed, and summary[1] means the HP distribution when the combatant is
slowed. However, if the combatant was already slowed before the battle,
summary[0] was the HP distribution when the combatant is slowed and
summary[1] was empty.

This optimization didn't break anything, thanks to itself: because the
"A slowed" or "B slowed" plane wasn't used, the code fetched the
HP distribution from summary[0] instead of summary[1] and therefore
obtained the correct distribution.

However, my Monte Carlo simulation code requires that summary[0] and
summary[1] have their usual meanings. I decided that the optimization is
too hard to support, and removed it.
This commit is contained in:
Jyrki Vesterinen 2016-07-16 13:13:48 +03:00
parent c43f70418f
commit d83e017689
1 changed files with 13 additions and 12 deletions
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25
src/attack_prediction.cpp
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@ -398,16 +398,15 @@ prob_matrix::prob_matrix(unsigned int a_max, unsigned int b_max,
if ( !b_initial[1].empty() )
initialize_plane(B_SLOWED, a_cur, b_cur, a_initial[0], b_initial[1]);
if ( !a_initial[1].empty() && !b_initial[1].empty() )
// Currently will not happen, but to be complete...
initialize_plane(BOTH_SLOWED, a_cur, b_cur, a_initial[1], b_initial[1]);
// Some debugging messages.
if ( !a_initial[0].empty() ) {
debug(("A has fought before.\n"));
debug(("A has fought before (or is slowed).\n"));
dump();
}
else if ( !b_initial[0].empty() ) {
debug(("B has fought before.\n"));
if ( !b_initial[0].empty() ) {
debug(("B has fought before (or is slowed).\n"));
dump();
}
}
@ -1493,6 +1492,14 @@ combatant::combatant(const battle_context_unit_stats &u, const combatant *prev)
untouched = 1.0;
poisoned = u.is_poisoned ? 1.0 : 0.0;
slowed = u.is_slowed ? 1.0 : 0.0;
// If we're already slowed, create summary[1] so that probability calculation code
// knows that we're slowed.
if (u.is_slowed)
{
summary[0].resize(u.max_hp + 1, 0.0);
summary[1] = hp_dist;
}
}
}
@ -1774,14 +1781,8 @@ void complex_fight(attack_prediction_mode mode,
probability_combat_matrix* pm = new probability_combat_matrix(stats.max_hp, opp_stats.max_hp,
stats.hp, opp_stats.hp, summary, opp_summary,
/* FIXME: due to this stupid optimization (not creating the slowed planes if the
combatant is already slowed), the combatant summary will have a different meaning than
usual if the combatant was already slowed (summary[0] will mean the slowed health
distribution, and summary[1] will be empty). That, in turn, will break the damage
calculation if another battle is later predicted for the same unit using Monte Carlo
simulation, since the MC simulation mode requires that summary has its usual meaning. */
stats.slows && !opp_stats.is_slowed,
opp_stats.slows && !stats.is_slowed,
stats.slows || opp_stats.is_slowed,
opp_stats.slows || stats.is_slowed,
a_damage, b_damage, a_slow_damage, b_slow_damage,
stats.drain_percent, opp_stats.drain_percent,
stats.drain_constant, opp_stats.drain_constant);