Improved hit calculation according to SOC/CS/COP formulas (#382, #392)

Xottab-DUTY · Xottab-DUTY · commit dd84bcebde02 · 2025-07-02T22:01:53.000+03:00
Engine now correctly uses hit_fraction_actor/hit_fraction_npc/hit_fraction from COP/CS/SOC.
I used a hacky solution to determine which formula to use, though:
Since hit_fraction_actor exists both in CS and COP, but fire_wound_protection was removed in COP, its presence or absence is used to distinguish between CS and COP.
diff --git a/src/xrGame/ActorHelmet.cpp b/src/xrGame/ActorHelmet.cpp
@@ -229,8 +229,8 @@ float CHelmet::HitThroughArmor(float hit_power, s16 element, float ap, bool& add
             if (!IsGameTypeSingle())
             {
                 float hit_fraction = (ap - BoneArmor) / ap;
-                if (hit_fraction < m_boneProtection->m_fHitFracActor)
-                    hit_fraction = m_boneProtection->m_fHitFracActor;
+                if (hit_fraction < m_boneProtection->m_fHitFrac)
+                    hit_fraction = m_boneProtection->m_fHitFrac;
 
                 NewHitPower *= hit_fraction;
                 NewHitPower *= m_boneProtection->getBoneProtection(element);
@@ -241,7 +241,7 @@ float CHelmet::HitThroughArmor(float hit_power, s16 element, float ap, bool& add
         else
         {
             //пуля НЕ пробила бронь
-            NewHitPower *= m_boneProtection->m_fHitFracActor;
+            NewHitPower *= m_boneProtection->m_fHitFrac;
             add_wound = false; //раны нет
         }
     }
diff --git a/src/xrGame/BoneProtections.cpp b/src/xrGame/BoneProtections.cpp
@@ -2,7 +2,7 @@
 #include "BoneProtections.h"
 #include "Include/xrRender/Kinematics.h"
 #include "xrCore/Animation/Bone.hpp"
-#include "Level.h"
+#include "game_type.h"
 
 float SBoneProtections::getBoneProtection(s16 bone_id) const
 {
@@ -35,20 +35,34 @@ void SBoneProtections::reload(const shared_str& bone_sect, IKinematics* kinemati
 {
     VERIFY(kinematics);
 
-    float defaultHitFraction = 0.1f;
-    if (ShadowOfChernobylMode || ClearSkyMode)
+    if (m_hitFracType != HitFractionActorCS && m_hitFracType != HitFractionActorCOP)
     {
-        defaultHitFraction = pSettings->read_if_exists<float>(bone_sect, "hit_fraction", defaultHitFraction);
+        if (pSettings->line_exist(bone_sect, HIT_FRACTION_NPC))
+        {
+            m_hitFracType = HitFractionNPC;
+            m_fHitFrac = pSettings->r_float(bone_sect, HIT_FRACTION_NPC);
+        }
+        else if (pSettings->line_exist(bone_sect, HIT_FRACTION))
+        {
+            m_hitFracType = HitFraction;
+            m_fHitFrac = pSettings->r_float(bone_sect, HIT_FRACTION);
+        }
+        else
+        {
+            m_fHitFrac = 0.1f;
+            m_hitFracType = HitFractionNPC;
+        }
     }
-    m_fHitFracNpc = pSettings->read_if_exists<float>(bone_sect, "hit_fraction_npc", defaultHitFraction);
 
     m_bones_koeff.clear();
     m_bones_koeff[BI_NONE] = BoneProtection{};
 
     CInifile::Sect& protections = pSettings->r_section(bone_sect);
     for (const auto& [name, value] : protections.Data)
     {
-        if (xr_strcmp(name.c_str(), "hit_fraction") == 0)
+        if (xr_strcmp(name.c_str(), HIT_FRACTION) == 0)
+            continue;
+        if (xr_strcmp(name.c_str(), HIT_FRACTION_NPC) == 0)
             continue;
 
         string256 buffer;
@@ -85,17 +99,17 @@ void SBoneProtections::add(const shared_str& bone_sect, IKinematics* kinematics)
 
     VERIFY(kinematics);
 
-    float defaultHitFraction = 0.0f;
-    if (ShadowOfChernobylMode || ClearSkyMode)
-    {
-        defaultHitFraction = READ_IF_EXISTS(pSettings, r_float, bone_sect, "hit_fraction", defaultHitFraction);
-    }
-    m_fHitFracNpc += READ_IF_EXISTS(pSettings, r_float, bone_sect.c_str(), "hit_fraction_npc", defaultHitFraction);
+    if (m_hitFracType == HitFractionNPC)
+        m_fHitFrac += pSettings->read_if_exists<float>(bone_sect, HIT_FRACTION_NPC, 0.0f);
+    else if (m_hitFracType == HitFraction)
+        m_fHitFrac += pSettings->read_if_exists<float>(bone_sect, HIT_FRACTION, 0.0f);
 
     CInifile::Sect& protections = pSettings->r_section(bone_sect);
     for (const auto& [name, value] : protections.Data)
     {
-        if (xr_strcmp(name.c_str(), "hit_fraction") == 0)
+        if (xr_strcmp(name.c_str(), HIT_FRACTION) == 0)
+            continue;
+        if (xr_strcmp(name.c_str(), HIT_FRACTION_NPC) == 0)
             continue;
 
         string256 buffer;
diff --git a/src/xrGame/BoneProtections.h b/src/xrGame/BoneProtections.h
@@ -4,6 +4,24 @@ class IKinematics;
 
 struct SBoneProtections
 {
+    static constexpr cpcstr HIT_FRACTION     = "hit_fraction";
+    static constexpr cpcstr HIT_FRACTION_NPC = "hit_fraction_npc";
+
+    enum HitFractionType : u8
+    {
+        // Exists in SOC and CS
+        HitFraction,
+
+        // Introduced in CS, externally assigned
+        HitFractionActorCS,
+
+        // Introduced in COP
+        HitFractionNPC,
+
+        // Hit formula changed in COP, externally assigned
+        HitFractionActorCOP,
+    };
+
     struct BoneProtection
     {
         float koeff{ 1.0f };
@@ -13,8 +31,8 @@ struct SBoneProtections
 
     mutable xr_map<s16, BoneProtection> m_bones_koeff;
 
-    float m_fHitFracNpc{ 0.1f };
-    float m_fHitFracActor{ 0.1f };
+    float m_fHitFrac{ 0.1f };
+    HitFractionType m_hitFracType{ HitFractionNPC };
 
     [[nodiscard]] float getBoneProtection(s16 bone_id) const;
     [[nodiscard]] float getBoneArmor(s16 bone_id) const;
diff --git a/src/xrGame/CustomOutfit.cpp b/src/xrGame/CustomOutfit.cpp
@@ -66,11 +66,24 @@ void CCustomOutfit::Load(LPCSTR section)
     m_HitTypeProtection[ALife::eHitTypeTelepatic] = pSettings->r_float(section, "telepatic_protection");
     m_HitTypeProtection[ALife::eHitTypeChemicalBurn] = pSettings->r_float(section, "chemical_burn_protection");
     m_HitTypeProtection[ALife::eHitTypeExplosion] = pSettings->r_float(section, "explosion_protection");
-    m_HitTypeProtection[ALife::eHitTypeFireWound] = 0.f; // pSettings->r_float(section,"fire_wound_protection");
+    m_HitTypeProtection[ALife::eHitTypeFireWound] = pSettings->read_if_exists<float>(section, "fire_wound_protection", 0.0f);
     m_HitTypeProtection[ALife::eHitTypePhysicStrike] = pSettings->read_if_exists<float>(
         section, "physic_strike_protection", m_HitTypeProtection[ALife::eHitTypeStrike]);
     m_HitTypeProtection[ALife::eHitTypeLightBurn] = m_HitTypeProtection[ALife::eHitTypeBurn];
-    m_boneProtection->m_fHitFracActor = pSettings->read_if_exists<float>(section, "hit_fraction_actor", 0.1f);
+
+    if (pSettings->line_exist(section, "hit_fraction_actor"))
+    {
+        m_boneProtection->m_fHitFrac = pSettings->r_float(section, "hit_fraction_actor");
+
+        // Since hit_fraction_actor exists both in CS and COP, but fire_wound_protection was removed in COP,
+        // We can use this hacky solution to determine which damage formula to use.
+        // It not robust for mods, because they can have fire_wound_protection in configs, despite that
+        // original COP engine doesn't read it.
+        if (pSettings->line_exist(section, "fire_wound_protection"))
+            m_boneProtection->m_hitFracType = SBoneProtections::HitFractionActorCS;
+        else
+            m_boneProtection->m_hitFracType = SBoneProtections::HitFractionActorCOP;
+    }
 
     if (pSettings->line_exist(section, "nightvision_sect"))
         m_NightVisionSect = pSettings->r_string(section, "nightvision_sect");
@@ -124,14 +137,23 @@ void CCustomOutfit::Hit(float hit_power, ALife::EHitType hit_type)
 
 float CCustomOutfit::GetDefHitTypeProtection(ALife::EHitType hit_type) const
 {
-    return m_HitTypeProtection[hit_type] * GetCondition();
+    const float base = m_HitTypeProtection[hit_type] * GetCondition();
+
+    if (m_boneProtection->m_hitFracType == SBoneProtections::HitFraction)
+        return 1.0f - base; // SOC
+
+    return base; // CS/COP
 }
 
 float CCustomOutfit::GetHitTypeProtection(ALife::EHitType hit_type, s16 element) const
 {
-    float fBase = m_HitTypeProtection[hit_type] * GetCondition();
-    float bone = m_boneProtection->getBoneProtection(element);
-    return fBase * bone;
+    const float base = m_HitTypeProtection[hit_type] * GetCondition();
+    const float bone = m_boneProtection->getBoneProtection(element);
+
+    if (m_boneProtection->m_hitFracType == SBoneProtections::HitFraction)
+        return 1.0f - base * bone; // SOC
+
+    return base * bone; // CS/COP
 }
 
 float CCustomOutfit::GetBoneArmor(s16 element) const
@@ -142,51 +164,131 @@ float CCustomOutfit::GetBoneArmor(s16 element) const
 float CCustomOutfit::HitThroughArmor(float hit_power, s16 element, float ap, bool& add_wound, ALife::EHitType hit_type)
 {
     float NewHitPower = hit_power;
-    if (hit_type == ALife::eHitTypeFireWound)
-    {
-        float ba = GetBoneArmor(element);
-        if (ba < 0.0f)
-            return NewHitPower;
 
-        float BoneArmor = ba * GetCondition();
-        if (/*!fis_zero(ba, EPS) && */ (ap > BoneArmor))
+    switch (m_boneProtection->m_hitFracType)
+    {
+    default:
+    case SBoneProtections::HitFractionActorCOP:
+    {
+        if (hit_type == ALife::eHitTypeFireWound)
         {
-            //пуля пробила бронь
-            if (!IsGameTypeSingle())
+            const float ba = GetBoneArmor(element);
+            if (ba < 0.0f)
+                return NewHitPower;
+
+            float BoneArmor = ba * GetCondition();
+            if (/*!fis_zero(ba, EPS) &&*/ ap > BoneArmor)
             {
-                float hit_fraction = (ap - BoneArmor) / ap;
-                if (hit_fraction < m_boneProtection->m_fHitFracActor)
-                    hit_fraction = m_boneProtection->m_fHitFracActor;
+                //пуля пробила бронь
+                if (!IsGameTypeSingle())
+                {
+                    float hit_fraction = (ap - BoneArmor) / ap;
+                    if (hit_fraction < m_boneProtection->m_fHitFrac)
+                        hit_fraction = m_boneProtection->m_fHitFrac;
+
+                    NewHitPower *= hit_fraction;
+                    NewHitPower *= m_boneProtection->getBoneProtection(element);
+                }
 
-                NewHitPower *= hit_fraction;
-                NewHitPower *= m_boneProtection->getBoneProtection(element);
+                VERIFY(NewHitPower >= 0.0f);
             }
+            else
+            {
+                //пуля НЕ пробила бронь
+                NewHitPower *= m_boneProtection->m_fHitFrac;
+                add_wound = false; 	//раны нет
+            }
+        }
+        else
+        {
+            float one = 0.1f;
+            if (hit_type == ALife::eHitTypeStrike ||
+                hit_type == ALife::eHitTypeWound ||
+                hit_type == ALife::eHitTypeWound_2 ||
+                hit_type == ALife::eHitTypeExplosion)
+            {
+                one = 1.0f;
+            }
+            const float protect = GetDefHitTypeProtection(hit_type);
+            NewHitPower -= protect * one;
 
-            VERIFY(NewHitPower >= 0.0f);
+            if (NewHitPower < 0.f)
+                NewHitPower = 0.f;
+        }
+
+        //увеличить изношенность костюма
+        Hit(hit_power, hit_type);
+        break;
+    }
+    case SBoneProtections::HitFractionActorCS:
+    {
+        if (hit_type == ALife::eHitTypeFireWound)
+        {
+            const float BoneArmor = m_boneProtection->getBoneArmor(element) * GetCondition();
+
+            if (ap > EPS && ap > BoneArmor)
+            {
+                //пуля пробила бронь
+                const float d_ap = ap - BoneArmor;
+                NewHitPower *= (d_ap / ap);
+
+                if (NewHitPower < m_boneProtection->m_fHitFrac)
+                    NewHitPower = m_boneProtection->m_fHitFrac;
+
+                if (!IsGameTypeSingle())
+                {
+                    NewHitPower *= m_boneProtection->getBoneProtection(element);
+                }
+
+                if (NewHitPower < 0.0f)
+                    NewHitPower = 0.0f;
+            }
+            else
+            {
+                //пуля НЕ пробила бронь
+                NewHitPower *= m_boneProtection->m_fHitFrac;
+                add_wound = false; //раны нет
+            }
         }
         else
         {
-            //пуля НЕ пробила бронь
-            NewHitPower *= m_boneProtection->m_fHitFracActor;
-            add_wound = false; //раны нет
+            float one = 0.1f;
+            if (hit_type == ALife::eHitTypeWound ||
+                hit_type == ALife::eHitTypeWound_2 ||
+                hit_type == ALife::eHitTypeExplosion)
+            {
+                one = 1.0f;
+            }
+
+            const float protect = GetHitTypeProtection(hit_type, element);
+            NewHitPower -= protect * one;
+            if (NewHitPower < 0.0f)
+                NewHitPower = 0.0f;
         }
+
+        //увеличить изношенность костюма
+        Hit(NewHitPower, hit_type);
+        break;
     }
-    else
+    case SBoneProtections::HitFraction:
     {
-        float one = 0.1f;
-        if (hit_type == ALife::eHitTypeStrike || hit_type == ALife::eHitTypeWound ||
-            hit_type == ALife::eHitTypeWound_2 || hit_type == ALife::eHitTypeExplosion)
+        if (hit_type == ALife::eHitTypeFireWound)
         {
-            one = 1.0f;
+            const float BoneArmor = m_boneProtection->getBoneArmor(element) * GetCondition() * (1 - ap);
+            NewHitPower -= BoneArmor;
+            if (NewHitPower < hit_power * m_boneProtection->m_fHitFrac)
+                NewHitPower = hit_power * m_boneProtection->m_fHitFrac;
+        }
+        else
+        {
+            NewHitPower *= GetHitTypeProtection(hit_type, element);
         }
-        float protect = GetDefHitTypeProtection(hit_type);
-        NewHitPower -= protect * one;
 
-        if (NewHitPower < 0.f)
-            NewHitPower = 0.f;
+        //увеличить изношенность костюма
+        Hit(hit_power, hit_type);
+        break;
     }
-    //увеличить изношенность костюма
-    Hit(hit_power, hit_type);
+    } // switch (m_boneProtection->m_hitFracType)
 
     return NewHitPower;
 }
@@ -285,6 +387,21 @@ u32 CCustomOutfit::ef_equipment_type() const
     return m_ef_equipment_type;
 }
 
+float CCustomOutfit::GetPowerLoss() const
+{
+    // Hit fraction and power loss are unrelated,
+    // but it's the only way we can distinguish between SOC/CS and COP.
+    // Sorry.
+    if (m_boneProtection->m_hitFracType != SBoneProtections::HitFractionActorCOP)
+    {
+        if (m_fPowerLoss < 1 && GetCondition() <= 0)
+        {
+            return 1.0f;
+        }
+    }
+    return m_fPowerLoss;
+};
+
 bool CCustomOutfit::install_upgrade_impl(LPCSTR section, bool test)
 {
     bool result = inherited::install_upgrade_impl(section, test);
@@ -326,10 +443,13 @@ bool CCustomOutfit::install_upgrade_impl(LPCSTR section, bool test)
     result2 = process_if_exists_set(section, "bones_koeff_protection_add", &CInifile::r_string, str, test);
     if (result2 && !test)
         AddBonesProtection(str);
-
     result |= result2;
-    result |=
-        process_if_exists(section, "hit_fraction_actor", &CInifile::r_float, m_boneProtection->m_fHitFracActor, test);
+
+    if (m_boneProtection->m_hitFracType == SBoneProtections::HitFractionActorCS ||
+        m_boneProtection->m_hitFracType == SBoneProtections::HitFractionActorCOP)
+    {
+        result |= process_if_exists(section, "hit_fraction_actor", &CInifile::r_float, m_boneProtection->m_fHitFrac, test);
+    }
 
     result |= process_if_exists(section, "additional_inventory_weight", &CInifile::r_float, m_additional_weight, test);
     result |=
diff --git a/src/xrGame/CustomOutfit.h b/src/xrGame/CustomOutfit.h
@@ -25,6 +25,10 @@ class CCustomOutfit : public CInventoryItemObject
     [[nodiscard]] float GetDefHitTypeProtection(ALife::EHitType hit_type) const;
     [[nodiscard]] float GetBoneArmor(s16 element) const;
 
+    //коэффициент на который домножается потеря силы
+    //если на персонаже надет костюм
+    [[nodiscard]] float GetPowerLoss() const;
+
     float HitThroughArmor(float hit_power, s16 element, float ap, bool& add_wound, ALife::EHitType hit_type);
 
     virtual void OnMoveToSlot(const SInvItemPlace& prev);
diff --git a/src/xrGame/EntityCondition.cpp b/src/xrGame/EntityCondition.cpp
diff --git a/src/xrGame/ai/stalker/ai_stalker_fire.cpp b/src/xrGame/ai/stalker/ai_stalker_fire.cpp

Original file line number	Diff line number	Diff line change
`@@ -229,8 +229,8 @@ float CHelmet::HitThroughArmor(float hit_power, s16 element, float ap, bool& add`
`229`	`229`	`if (!IsGameTypeSingle())`
`230`	`230`	`{`
`231`	`231`	`float hit_fraction = (ap - BoneArmor) / ap;`
`232`		`- if (hit_fraction < m_boneProtection->m_fHitFracActor)`
`233`		`- hit_fraction = m_boneProtection->m_fHitFracActor;`
	`232`	`+ if (hit_fraction < m_boneProtection->m_fHitFrac)`
	`233`	`+ hit_fraction = m_boneProtection->m_fHitFrac;`
`234`	`234`
`235`	`235`	`NewHitPower *= hit_fraction;`
`236`	`236`	`NewHitPower *= m_boneProtection->getBoneProtection(element);`
`@@ -241,7 +241,7 @@ float CHelmet::HitThroughArmor(float hit_power, s16 element, float ap, bool& add`
`241`	`241`	`else`
`242`	`242`	`{`
`243`	`243`	`//пуля НЕ пробила бронь`
`244`		`- NewHitPower *= m_boneProtection->m_fHitFracActor;`
	`244`	`+ NewHitPower *= m_boneProtection->m_fHitFrac;`
`245`	`245`	`add_wound = false; //раны нет`
`246`	`246`	`}`
`247`	`247`	`}`