Move spell magicka cost calculation to standalone function

apps/openmw/mwgui/spellcreationdialog.cpp

@@ -440,22 +440,11 @@ namespace MWGui
 
         for (std::vector<ESM::ENAMstruct>::const_iterator it = mEffects.begin(); it != mEffects.end(); ++it)
         {
-            float x = 0.5f * (it->mMagnMin + it->mMagnMax);
+            const ESM::ENAMstruct& effect = *it;
 
-            const ESM::MagicEffect* effect =
+            y += std::max(1.f, MWMechanics::calcEffectCost(effect));
-                store.get<ESM::MagicEffect>().find(it->mEffectID);
 
-            x *= 0.1f * effect->mData.mBaseCost;
+            if (effect.mRange == ESM::RT_Target)
-            x *= 1 + it->mDuration;
-            x += 0.05f * std::max(1, it->mArea) * effect->mData.mBaseCost;
-
-            float fEffectCostMult =
-                store.get<ESM::GameSetting>().find("fEffectCostMult")->getFloat();
-
-            y += x * fEffectCostMult;
-            y = std::max(1.f,y);
-
-            if (it->mRange == ESM::RT_Target)
                 y *= 1.5;
         }
 
@@ -475,8 +464,10 @@ namespace MWGui
 
         mPriceLabel->setCaption(MyGUI::utility::toString(int(price)));
 
-        float chance = MWMechanics::getSpellSuccessChance(&mSpell, MWMechanics::getPlayer());
+        float chance = MWMechanics::calcSpellBaseSuccessChance(&mSpell, MWMechanics::getPlayer(), NULL);
-        mSuccessChance->setCaption(MyGUI::utility::toString(int(chance)));
+
+        int intChance = std::min(100, int(chance));
+        mSuccessChance->setCaption(MyGUI::utility::toString(intChance));
     }
 
     // ------------------------------------------------------------------------------------------------

apps/openmw/mwmechanics/aicombataction.cpp

@@ -593,16 +593,7 @@ namespace MWMechanics
             }
         }
 
-        rating *= ((effect.mMagnMin + effect.mMagnMax) * (effect.mDuration > 0 ? effect.mDuration : 1) + effect.mArea);
+        rating *= calcEffectCost(effect);
-        rating *= magicEffect->mData.mBaseCost;
-
-        if (effect.mRange == ESM::RT_Target)
-            rating *= 1.5f;
-
-        static const float fEffectCostMult = MWBase::Environment::get().getWorld()->getStore().get<ESM::GameSetting>().find(
-                    "fEffectCostMult")->getFloat();
-
-        rating *= fEffectCostMult * 0.05;
 
         // Currently treating all "on target" or "on touch" effects to target the enemy actor.
         // Combat AI is egoistic, so doesn't consider applying positive effects to friendly actors.
@@ -619,6 +610,9 @@ namespace MWMechanics
         for (std::vector<ESM::ENAMstruct>::const_iterator it = list.mList.begin(); it != list.mList.end(); ++it)
         {
             rating += rateEffect(*it, actor, enemy);
+
+            if (it->mRange == ESM::RT_Target)
+                rating *= 1.5f;
         }
         return rating;
     }

apps/openmw/mwmechanics/autocalcspell.cpp

@@ -1,4 +1,5 @@
 #include "autocalcspell.hpp"
+#include "spellcasting.hpp"
 
 #include <climits>
 #include <limits>
@@ -255,27 +256,39 @@ namespace MWMechanics
 
     void calcWeakestSchool (const ESM::Spell* spell, const int* actorSkills, int& effectiveSchool, float& skillTerm)
     {
+        // Morrowind for some reason uses a formula slightly different from magicka cost calculation
         float minChance = std::numeric_limits<float>::max();
 
         const ESM::EffectList& effects = spell->mEffects;
         for (std::vector<ESM::ENAMstruct>::const_iterator it = effects.mList.begin(); it != effects.mList.end(); ++it)
         {
             const ESM::ENAMstruct& effect = *it;
-            float x = static_cast<float>(effect.mDuration);
-
             const ESM::MagicEffect* magicEffect = MWBase::Environment::get().getWorld()->getStore().get<ESM::MagicEffect>().find(effect.mEffectID);
-            if (!(magicEffect->mData.mFlags & ESM::MagicEffect::UncappedDamage))
-                x = std::max(1.f, x);
 
-            x *= 0.1f * magicEffect->mData.mBaseCost;
+            int minMagn = 1;
-            x *= 0.5f * (effect.mMagnMin + effect.mMagnMax);
+            int maxMagn = 1;
-            x += effect.mArea * 0.05f * magicEffect->mData.mBaseCost;
+            if (!(magicEffect->mData.mFlags & ESM::MagicEffect::NoMagnitude))
+            {
+                minMagn = effect.mMagnMin;
+                maxMagn = effect.mMagnMax;
+            }
+
+            int duration = 0;
+            if (!(magicEffect->mData.mFlags & ESM::MagicEffect::NoDuration))
+                duration = effect.mDuration;
+
+            static const float fEffectCostMult = MWBase::Environment::get().getWorld()->getStore()
+                .get<ESM::GameSetting>().find("fEffectCostMult")->getFloat();
+
+            float x = 0.5 * (std::max(1, minMagn) + std::max(1, maxMagn));
+            x *= 0.1 * magicEffect->mData.mBaseCost;
+            x *= 1 + duration;
+            x += 0.05 * std::max(1, effect.mArea) * magicEffect->mData.mBaseCost;
+            x *= fEffectCostMult;
+
             if (effect.mRange == ESM::RT_Target)
                 x *= 1.5f;
 
-            static const float fEffectCostMult = MWBase::Environment::get().getWorld()->getStore().get<ESM::GameSetting>().find("fEffectCostMult")->getFloat();
-            x *= fEffectCostMult;
-
             float s = 2.f * actorSkills[mapSchoolToSkill(magicEffect->mData.mSchool)];
             if (s - x < minChance)
             {

apps/openmw/mwmechanics/spellcasting.cpp

@@ -44,8 +44,36 @@ namespace MWMechanics
         return schoolSkillMap[school];
     }
 
-    float getSpellSuccessChance (const ESM::Spell* spell, const MWWorld::Ptr& actor, int* effectiveSchool, bool cap)
+    float calcEffectCost(const ESM::ENAMstruct& effect)
     {
+        const ESM::MagicEffect* magicEffect = MWBase::Environment::get().getWorld()->getStore().get<ESM::MagicEffect>().find(effect.mEffectID);
+
+        int minMagn = 1;
+        int maxMagn = 1;
+        if (!(magicEffect->mData.mFlags & ESM::MagicEffect::NoMagnitude))
+        {
+            minMagn = effect.mMagnMin;
+            maxMagn = effect.mMagnMax;
+        }
+
+        int duration = 0;
+        if (!(magicEffect->mData.mFlags & ESM::MagicEffect::NoDuration))
+            duration = effect.mDuration;
+
+        static const float fEffectCostMult = MWBase::Environment::get().getWorld()->getStore()
+            .get<ESM::GameSetting>().find("fEffectCostMult")->getFloat();
+
+        float x = 0.5 * (std::max(1, minMagn) + std::max(1, maxMagn));
+        x *= 0.1 * magicEffect->mData.mBaseCost;
+        x *= 1 + duration;
+        x += 0.05 * std::max(1, effect.mArea) * magicEffect->mData.mBaseCost;
+
+        return x * fEffectCostMult;
+    }
+
+    float calcSpellBaseSuccessChance (const ESM::Spell* spell, const MWWorld::Ptr& actor, int* effectiveSchool)
+    {
+        // Morrowind for some reason uses a formula slightly different from magicka cost calculation
         float y = std::numeric_limits<float>::max();
         float lowestSkill = 0;
 
@@ -54,8 +82,10 @@ namespace MWMechanics
             float x = static_cast<float>(it->mDuration);
             const ESM::MagicEffect* magicEffect = MWBase::Environment::get().getWorld()->getStore().get<ESM::MagicEffect>().find(
                         it->mEffectID);
+
             if (!(magicEffect->mData.mFlags & ESM::MagicEffect::UncappedDamage))
                 x = std::max(1.f, x);
+
             x *= 0.1f * magicEffect->mData.mBaseCost;
             x *= 0.5f * (it->mMagnMin + it->mMagnMax);
             x *= it->mArea * 0.05f * magicEffect->mData.mBaseCost;
@@ -75,6 +105,18 @@ namespace MWMechanics
             }
         }
 
+        CreatureStats& stats = actor.getClass().getCreatureStats(actor);
+
+        int actorWillpower = stats.getAttribute(ESM::Attribute::Willpower).getModified();
+        int actorLuck = stats.getAttribute(ESM::Attribute::Luck).getModified();
+
+        float castChance = (lowestSkill - spell->mData.mCost + 0.2f * actorWillpower + 0.1f * actorLuck);
+
+        return castChance;
+    }
+
+    float getSpellSuccessChance (const ESM::Spell* spell, const MWWorld::Ptr& actor, int* effectiveSchool, bool cap)
+    {
         bool godmode = actor == MWMechanics::getPlayer() && MWBase::Environment::get().getWorld()->getGodModeState();
 
         CreatureStats& stats = actor.getClass().getCreatureStats(actor);
@@ -98,10 +140,8 @@ namespace MWMechanics
 
         float castBonus = -stats.getMagicEffects().get(ESM::MagicEffect::Sound).getMagnitude();
 
-        int actorWillpower = stats.getAttribute(ESM::Attribute::Willpower).getModified();
+        float castChance = calcSpellBaseSuccessChance(spell, actor, effectiveSchool) + castBonus;
-        int actorLuck = stats.getAttribute(ESM::Attribute::Luck).getModified();
+        castChance *= stats.getFatigueTerm();
-
-        float castChance = (lowestSkill - spell->mData.mCost + castBonus + 0.2f * actorWillpower + 0.1f * actorLuck) * stats.getFatigueTerm();
 
         if (!cap)
             return std::max(0.f, castChance);

apps/openmw/mwmechanics/spellcasting.hpp

@@ -1,6 +1,7 @@
 #ifndef MWMECHANICS_SPELLSUCCESS_H
 #define MWMECHANICS_SPELLSUCCESS_H
 
+#include <components/esm/effectlist.hpp>
 #include <components/esm/loadskil.hpp>
 
 #include "../mwworld/ptr.hpp"
@@ -21,6 +22,8 @@ namespace MWMechanics
 
     ESM::Skill::SkillEnum spellSchoolToSkill(int school);
 
+    float calcEffectCost(const ESM::ENAMstruct& effect);
+
     bool isSummoningEffect(int effectId);
 
     /**
@@ -62,6 +65,7 @@ namespace MWMechanics
     bool checkEffectTarget (int effectId, const MWWorld::Ptr& target, const MWWorld::Ptr& caster, bool castByPlayer);
 
     int getEffectiveEnchantmentCastCost (float castCost, const MWWorld::Ptr& actor);
+    float calcSpellBaseSuccessChance (const ESM::Spell* spell, const MWWorld::Ptr& actor, int* effectiveSchool);
 
     /// Apply a magic effect that is applied in tick intervals until its remaining time ends or it is removed
     /// @return Was the effect a tickable effect with a magnitude?