Added the script-only function Entity::createScriptObject() for convenience. This is for cases where only the script object is significant, instead of the ScriptInstance component that is also created at the same time.

Bin/Data/Scripts/GameObject.as

@@ -90,10 +90,8 @@ class GameObject : ScriptObject
     {
         Entity@ newEntity = scene.createEntity();
 
-        // Create the ScriptInstance with specified class
-        ScriptInstance@ instance = newEntity.createComponent("ScriptInstance");
-        instance.setScriptClass(cache.getResource("ScriptFile", "Scripts/NinjaSnowWar.as"), className);
-        GameObject@ object = cast<GameObject>(instance.getScriptObject());
+        // Create the script object with specified class
+        GameObject@ object = cast<GameObject>(newEntity.createScriptObject("Scripts/NinjaSnowWar.as", className));
         if (@object != null)
             object.create(position, rotation);
 
@@ -110,9 +108,7 @@ class GameObject : ScriptObject
         emitter.setPosition(position);
 
         // Create a GameObject for managing the effect lifetime
-        ScriptInstance@ instance = newEntity.createComponent("ScriptInstance");
-        instance.setScriptClass(cache.getResource("ScriptFile", "Scripts/NinjaSnowWar.as"), "GameObject");
-        GameObject@ object = cast<GameObject>(instance.getScriptObject());
+        GameObject@ object = cast<GameObject>(newEntity.createScriptObject("Scripts/NinjaSnowWar.as", "GameObject"));
         if (@object != null)
             object.duration = duration;
 
@@ -123,13 +119,6 @@ class GameObject : ScriptObject
     {
         Entity@ newEntity = scene.createEntity();
 
-        // Create a GameObject for managing the sound lifetime
-        ScriptInstance@ instance = newEntity.createComponent("ScriptInstance");
-        instance.setScriptClass(cache.getResource("ScriptFile", "Scripts/NinjaSnowWar.as"), "GameObject");
-        GameObject@ object = cast<GameObject>(instance.getScriptObject());
-        if (@object != null)
-            object.duration = duration;
-
         // Create the sound channel
         PositionalChannel@ channel = newEntity.createComponent("PositionalChannel");
         channel.setPosition(position);
@@ -138,6 +127,11 @@ class GameObject : ScriptObject
         Sound@ sound = cache.getResource("Sound", soundName);
         channel.play(sound, sound.getFrequency());
 
+        // Create a GameObject for managing the sound lifetime
+        GameObject@ object = cast<GameObject>(newEntity.createScriptObject("Scripts/NinjaSnowWar.as", "GameObject"));
+        if (@object != null)
+            object.duration = duration;
+
         return newEntity;
     }
 
@@ -153,7 +147,7 @@ class GameObject : ScriptObject
         // If the other entity is scripted, perform object-to-object collision
         GameObject@ otherObject = cast<GameObject>(otherEntity.getScriptObject());
         if (@otherObject != null)
-            objectCollision(otherEntity, otherObject, eventData);
+            objectCollision(otherObject, eventData);
     }
 
     void worldCollision(VariantMap& eventData)
@@ -188,7 +182,7 @@ class GameObject : ScriptObject
             isSliding = false;
     }
 
-    void objectCollision(Entity@ otherEntity, GameObject@ otherObject, VariantMap& eventData)
+    void objectCollision(GameObject@ otherObject, VariantMap& eventData)
     {
     }
 

Bin/Data/Scripts/NinjaSnowWar.as

@@ -159,9 +159,7 @@ void startGame()
         gameScene.removeEntity(scriptedEntities[i]);
 
     Entity@ playerEntity = gameScene.createEntity("Player");
-    ScriptInstance@ instance = playerEntity.createComponent("ScriptInstance");
-    instance.setScriptClass(cache.getResource("ScriptFile", "Scripts/NinjaSnowWar.as"), "Ninja");
-    GameObject@ object = cast<GameObject>(instance.getScriptObject());
+    GameObject@ object = cast<GameObject>(playerEntity.createScriptObject("Scripts/NinjaSnowWar.as", "Ninja"));
     object.create(Vector3(0, 90, 0), Quaternion());
     object.health = object.maxHealth = playerHealth;
     object.side = SIDE_PLAYER;

Bin/Data/Scripts/Potion.as

@@ -41,7 +41,7 @@ class Potion : GameObject
         body.addChild(model);
     }
     
-    void objectCollision(Entity@ otherEntity, GameObject@ otherObject, VariantMap& eventData)
+    void objectCollision(GameObject@ otherObject, VariantMap& eventData)
     {
         if (healAmount > 0)
         {

Bin/Data/Scripts/SnowBall.as

@@ -76,7 +76,7 @@ class SnowBall : GameObject
             duration = snowballGroundHitDuration;
     }
 
-    void objectCollision(Entity@ otherEntity, GameObject@ otherObject, VariantMap& eventData)
+    void objectCollision(GameObject@ otherObject, VariantMap& eventData)
     {
         if (hitDamage > 0)
         {

Engine/Engine/RegisterScene.cpp

@@ -24,6 +24,7 @@
 #include "Precompiled.h"
 #include "RegisterTemplates.h"
 #include "Scene.h"
+#include "ScriptFile.h"
 #include "ScriptInstance.h"
 
 static void ConstructComponentRef(ComponentRef* ptr)
@@ -117,6 +118,40 @@ static Component* EntityCreateComponentWithName(const std::string& type, const s
     }
 }
 
+static asIScriptObject* EntityCreateScriptObject(const std::string& scriptFileName, const std::string& className, Entity* ptr)
+{
+    try
+    {
+        ResourceCache* cache = getEngine()->getResourceCache();
+        ScriptFile* file = cache->getResource<ScriptFile>(scriptFileName);
+        if (!file)
+            return 0;
+        // Try first to reuse an existing, empty ScriptInstance
+        const std::vector<SharedPtr<Component> >& components = ptr->getComponents();
+        for (std::vector<SharedPtr<Component> >::const_iterator i = components.begin(); i != components.end(); ++i)
+        {
+            if ((*i)->getType() == ScriptInstance::getTypeStatic())
+            {
+                ScriptInstance* instance = static_cast<ScriptInstance*>(i->getPtr());
+                asIScriptObject* object = instance->getScriptObject();
+                if (!object)
+                {
+                    instance->setScriptClass(file, className);
+                    return instance->getScriptObject();
+                }
+            }
+        }
+        // Then create a new component if not found
+        ScriptInstance* instance = ptr->createComponent<ScriptInstance>(ptr->getUniqueComponentName());
+        instance->setScriptClass(file, className);
+        return instance->getScriptObject();
+    }
+    catch (Exception& e)
+    {
+        SAFE_RETHROW_RET(e, 0);
+    }
+}
+
 static void EntityRemoveComponent(const std::string& type, Entity* ptr)
 {
     ptr->removeComponent(ShortStringHash(type));
@@ -243,6 +278,7 @@ static void registerEntity(asIScriptEngine* engine)
     engine->RegisterObjectMethod("Entity", "void setPredictionFrom(Entity@+)", asMETHOD(Entity, setPredictionFrom), asCALL_THISCALL);
     engine->RegisterObjectMethod("Entity", "Component@+ createComponent(const string& in)", asFUNCTION(EntityCreateComponent), asCALL_CDECL_OBJLAST);
     engine->RegisterObjectMethod("Entity", "Component@+ createComponent(const string& in, const string& in)", asFUNCTION(EntityCreateComponentWithName), asCALL_CDECL_OBJLAST);
+    engine->RegisterObjectMethod("Entity", "ScriptObject@+ createScriptObject(const string& in, const string& in)", asFUNCTION(EntityCreateScriptObject), asCALL_CDECL_OBJLAST);
     engine->RegisterObjectMethod("Entity", "void addComponent(Component@+)", asMETHOD(Entity, addComponent), asCALL_THISCALL);
     engine->RegisterObjectMethod("Entity", "void removeComponent(Component@+)", asMETHODPR(Entity, removeComponent, (Component*), void), asCALL_THISCALL);
     engine->RegisterObjectMethod("Entity", "void removeComponent(const string& in)", asFUNCTION(EntityRemoveComponent), asCALL_CDECL_OBJLAST);