fix ai crit calculations

rh-hideout · Jun 9, 2024 · 1ca4676 · 1ca4676
1 parent db15190
commit 1ca4676
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Showing 3 changed files with 34 additions and 18 deletions.
diff --git a/include/battle_script_commands.h b/include/battle_script_commands.h
@@ -24,7 +24,7 @@ struct PickupItem
 
 s32 CalcCritChanceStageArgs(u32 battlerAtk, u32 battlerDef, u32 move, bool32 recordAbility, u32 abilityAtk, u32 abilityDef, u32 holdEffectAtk);
 s32 CalcCritChanceStage(u32 battlerAtk, u32 battlerDef, u32 move, bool32 recordAbility);
-s32 GetCritHitChance(s32 critChanceIndex);
+s32 GetCritHitOdds(s32 critChanceIndex);
 u32 GetTotalAccuracy(u32 battlerAtk, u32 battlerDef, u32 move, u32 atkAbility, u32 defAbility, u32 atkHoldEffect, u32 defHoldEffect);
 u8 GetBattlerTurnOrderNum(u8 battlerId);
 bool32 NoAliveMonsForPlayer(void);

diff --git a/src/battle_ai_util.c b/src/battle_ai_util.c
@@ -515,15 +515,23 @@ s32 AI_CalcDamage(u32 move, u32 battlerAtk, u32 battlerDef, u8 *typeEffectivenes
                                              aiData->abilities[battlerAtk], aiData->abilities[battlerDef]);
 
         critChanceIndex = CalcCritChanceStageArgs(battlerAtk, battlerDef, move, FALSE, aiData->abilities[battlerAtk], aiData->abilities[battlerDef], aiData->holdEffects[battlerAtk]);
-        if (critChanceIndex > 1) // Consider crit damage only if a move has at least +1 crit chance
+        if (critChanceIndex > 1) // Consider crit damage only if a move has at least +2 crit chance
         {
             s32 critDmg = CalculateMoveDamageVars(move, battlerAtk, battlerDef, moveType, fixedBasePower,
                                              effectivenessMultiplier, weather, TRUE,
                                              aiData->holdEffects[battlerAtk], aiData->holdEffects[battlerDef],
                                              aiData->abilities[battlerAtk], aiData->abilities[battlerDef]);
-            u32 critChance = GetCritHitChance(critChanceIndex);
-            // With critChance getting closer to 1, dmg gets closer to critDmg.
-            dmg = LowestRollDmg((critDmg + normalDmg * (critChance - 1)) / (critChance));
+            u32 critOdds = GetCritHitOdds(critChanceIndex); // Crit chance is 1/critOdds
+            // With critOdds getting closer to 1, dmg gets closer to critDmg.
+            dmg = LowestRollDmg((critDmg + normalDmg * (critOdds - 1)) / (critOdds));
+        }
+        else if (critChanceIndex == -2) // Guaranteed critical
+        {
+            s32 critDmg = CalculateMoveDamageVars(move, battlerAtk, battlerDef, moveType, fixedBasePower,
+                                             effectivenessMultiplier, weather, TRUE,
+                                             aiData->holdEffects[battlerAtk], aiData->holdEffects[battlerDef],
+                                             aiData->abilities[battlerAtk], aiData->abilities[battlerDef]);
+            dmg = LowestRollDmg(critDmg);
         }
         else
         {

diff --git a/src/battle_script_commands.c b/src/battle_script_commands.c
@@ -1905,20 +1905,19 @@ static void Cmd_ppreduce(void)
 
 // The chance is 1/N for each stage.
 #if B_CRIT_CHANCE >= GEN_7
-    static const u8 sCriticalHitChance[] = {24, 8, 2, 1, 1};
+    static const u8 sCriticalHitOdds[] = {24, 8, 2, 1, 1};
 #elif B_CRIT_CHANCE == GEN_6
-    static const u8 sCriticalHitChance[] = {16, 8, 2, 1, 1};
+    static const u8 sCriticalHitOdds[] = {16, 8, 2, 1, 1};
 #else
-    static const u8 sCriticalHitChance[] = {16, 8, 4, 3, 2}; // Gens 2,3,4,5
+    static const u8 sCriticalHitOdds[] = {16, 8, 4, 3, 2}; // Gens 2,3,4,5
 #endif // B_CRIT_CHANCE
 
 #define BENEFITS_FROM_LEEK(battler, holdEffect)((holdEffect == HOLD_EFFECT_LEEK) && (GET_BASE_SPECIES_ID(gBattleMons[battler].species) == SPECIES_FARFETCHD || gBattleMons[battler].species == SPECIES_SIRFETCHD))
 s32 CalcCritChanceStageArgs(u32 battlerAtk, u32 battlerDef, u32 move, bool32 recordAbility, u32 abilityAtk, u32 abilityDef, u32 holdEffectAtk)
 {
     s32 critChance = 0;
 
-    if (gSideStatuses[battlerDef] & SIDE_STATUS_LUCKY_CHANT
-        || abilityDef == ABILITY_BATTLE_ARMOR || abilityDef == ABILITY_SHELL_ARMOR)
+    if (gSideStatuses[battlerDef] & SIDE_STATUS_LUCKY_CHANT)
     {
         critChance = -1;
     }
@@ -1940,12 +1939,21 @@ s32 CalcCritChanceStageArgs(u32 battlerAtk, u32 battlerDef, u32 move, bool32 rec
                     + (abilityAtk == ABILITY_SUPER_LUCK)
                     + gBattleStruct->bonusCritStages[gBattlerAttacker];
 
-        // Record ability only if move had at least +3 chance to get a crit
-        if (critChance >= 3 && recordAbility && (abilityDef == ABILITY_BATTLE_ARMOR || abilityDef == ABILITY_SHELL_ARMOR))
-            RecordAbilityBattle(battlerDef, abilityDef);
+        if (critChance >= ARRAY_COUNT(sCriticalHitOdds))
+            critChance = ARRAY_COUNT(sCriticalHitOdds) - 1;
+    }
 
-        if (critChance >= ARRAY_COUNT(sCriticalHitChance))
-            critChance = ARRAY_COUNT(sCriticalHitChance) - 1;
+    if (critChance != -1 && (abilityDef == ABILITY_BATTLE_ARMOR || abilityDef == ABILITY_SHELL_ARMOR))
+    {
+        // Record ability only if move had 100% chance to get a crit
+        if (recordAbility)
+        {
+            if (critChance == -2)
+                RecordAbilityBattle(battlerDef, abilityDef);
+            else if (sCriticalHitOdds[critChance] == 1)
+                RecordAbilityBattle(battlerDef, abilityDef);
+        }
+        critChance = -1;
     }
 
     return critChance;
@@ -1960,12 +1968,12 @@ s32 CalcCritChanceStage(u32 battlerAtk, u32 battlerDef, u32 move, bool32 recordA
 }
 #undef BENEFITS_FROM_LEEK
 
-s32 GetCritHitChance(s32 critChanceIndex)
+s32 GetCritHitOdds(s32 critChanceIndex)
 {
     if (critChanceIndex < 0)
         return -1;
     else
-        return sCriticalHitChance[critChanceIndex];
+        return sCriticalHitOdds[critChanceIndex];
 }
 
 static void Cmd_critcalc(void)
@@ -1983,7 +1991,7 @@ static void Cmd_critcalc(void)
     else if (critChance == -2)
         gIsCriticalHit = TRUE;
     else
-        gIsCriticalHit = RandomWeighted(RNG_CRITICAL_HIT, sCriticalHitChance[critChance] - 1, 1);
+        gIsCriticalHit = RandomWeighted(RNG_CRITICAL_HIT, sCriticalHitOdds[critChance] - 1, 1);
 
     // Counter for EVO_CRITICAL_HITS.
     partySlot = gBattlerPartyIndexes[gBattlerAttacker];