Core/Spells: Remove spell range increase when caster or target move backwards

(cherry picked from commit f19e1a271618a35515512ce2a64330f21133616c)

3 files changed, 12 insertions, 3 deletions

diff --git a/src/server/game/Spells/Spell.cpp b/src/server/game/Spells/Spell.cpp
index 7e957b98db9..29a652721f3 100644
--- a/src/server/game/Spells/Spell.cpp
+++ b/src/server/game/Spells/Spell.cpp
@@ -7169,6 +7169,13 @@ SpellCastResult Spell::CheckRange(bool strict) const
     return SPELL_CAST_OK;
 }
 
+bool Spell::CanIncreaseRangeByMovement(Unit const* unit)
+{
+    // forward running only
+    return unit->HasUnitMovementFlag(MOVEMENTFLAG_FORWARD | MOVEMENTFLAG_STRAFE_LEFT | MOVEMENTFLAG_STRAFE_RIGHT | MOVEMENTFLAG_FALLING)
+        && !unit->IsWalking();
+}
+
 std::pair<float, float> Spell::GetMinMaxRange(bool strict) const
 {
     float rangeMod = 0.0f;
@@ -7210,7 +7217,7 @@ std::pair<float, float> Spell::GetMinMaxRange(bool strict) const
             }
         }
 
-        if (target && unitCaster && unitCaster->isMoving() && target->isMoving() && !unitCaster->IsWalking() && !target->IsWalking() &&
+        if (target && unitCaster && CanIncreaseRangeByMovement(target) && CanIncreaseRangeByMovement(unitCaster) &&
             ((m_spellInfo->RangeEntry->Flags & SPELL_RANGE_MELEE) || target->GetTypeId() == TYPEID_PLAYER))
             rangeMod += 8.0f / 3.0f;
     }
diff --git a/src/server/game/Spells/Spell.h b/src/server/game/Spells/Spell.h
index d28ce0f2ff8..cf27e5a1ff2 100644
--- a/src/server/game/Spells/Spell.h
+++ b/src/server/game/Spells/Spell.h
@@ -678,6 +678,8 @@ class TC_GAME_API Spell
         bool IsWithinLOS(WorldObject const* source, Position const& target, VMAP::ModelIgnoreFlags ignoreFlags) const;
         void MovePosition(Position& pos, WorldObject const* from, float dist, float angle) const;
 
+        static bool CanIncreaseRangeByMovement(Unit const* unit);
+
     protected:
         bool HasGlobalCooldown() const;
         void TriggerGlobalCooldown();
diff --git a/src/server/game/Spells/SpellInfo.cpp b/src/server/game/Spells/SpellInfo.cpp
index 2a89469fd4d..d079113b828 100644
--- a/src/server/game/Spells/SpellInfo.cpp
+++ b/src/server/game/Spells/SpellInfo.cpp
@@ -663,7 +663,7 @@ float SpellEffectInfo::CalcRadius(WorldObject* caster /*= nullptr*/, SpellTarget
 
     if (caster)
     {
-        if (Unit* casterUnit = caster->ToUnit())
+        if (Unit const* casterUnit = caster->ToUnit())
             radius += entry->RadiusPerLevel * casterUnit->GetLevel();
 
         radius = std::min(radius, entry->RadiusMax);
@@ -672,7 +672,7 @@ float SpellEffectInfo::CalcRadius(WorldObject* caster /*= nullptr*/, SpellTarget
             modOwner->ApplySpellMod(_spellInfo, SpellModOp::Radius, radius, spell);
 
         if (!_spellInfo->HasAttribute(SPELL_ATTR9_NO_MOVEMENT_RADIUS_BONUS))
-            if (Unit* casterUnit = caster->ToUnit(); casterUnit && casterUnit->isMoving() && !casterUnit->IsWalking())
+            if (Unit const* casterUnit = caster->ToUnit(); casterUnit && Spell::CanIncreaseRangeByMovement(casterUnit))
                 radius += 2.0f;
     }