HowTo/Upgrade GameObject.GetId() - Revision history

Pw3r: Pw3r moved page HowTo/Upgrade GameObject.GetId to HowTo/Upgrade GameObject.GetId() without leaving a redirect

2022-03-03T05:39:42Z

Pw3r moved page HowTo/Upgrade GameObject.GetId to HowTo/Upgrade GameObject.GetId() without leaving a redirect

← Older revision	Revision as of 05:39, 3 March 2022
(No difference)

Pw3r at 05:09, 3 March 2022

2022-03-03T05:09:07Z

← Older revision		Revision as of 05:09, 3 March 2022
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	* [[Compatibility_mode\|Compatibility Mode Setting]]		* [[Compatibility_mode\|Compatibility Mode Setting]]
	* [[HowTo/Upgrade_obsolete_script_functions\|How to Upgrade Obsolete Script Functions]]		* [[HowTo/Upgrade_obsolete_script_functions\|How to Upgrade Obsolete Script Functions]]
			<br>

	==Overview==		==Overview==

Pw3r at 05:06, 3 March 2022

2022-03-03T05:06:58Z

← Older revision		Revision as of 05:06, 3 March 2022
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	}		}

	Updating these calls to use GameObjectID is straightforward, and since we know the old approach was flawed ~~there is no need~~ to support reading it back in.		Updating these calls to use GameObjectID is straightforward, and since we know the old approach was flawed we explicitly do not want to support reading it back in.
	public Soup GetProperties(void)		public Soup GetProperties(void)
	{		{

Pw3r at 05:06, 3 March 2022

2022-03-03T05:06:20Z

@@ Line 122: / Line 122: @@
 It is worth noting that an object cannot have too many thread functions running on it at once, so too many calls to SetJunctionDirection() will result in a script exception with the error code ER_ThreadError.
 ==Saving/Loading an ID==
-==Logging an ID==
+Updating these calls to use GameObjectID is straightforward, and since we know the old approach was flawed there is no need to support reading it back in.

Pw3r at 04:39, 3 March 2022

2022-03-03T04:39:38Z

← Older revision		Revision as of 04:39, 3 March 2022
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	#The function will now force the tile/section which contains the junction object to be loaded into memory. If this junction set is gameplay critical, the forcing the tile to load is likely acceptable, but it does come with a performance cost and script should avoid doing this over multiple items.		#The function will now force the tile/section which contains the junction object to be loaded into memory. If this junction set is gameplay critical, the forcing the tile to load is likely acceptable, but it does come with a performance cost and script should avoid doing this over multiple items.
	#The function is now declared as a [[TrainzScript_Keywords#thread\|thread]]. Script threads allow an object to use function calls like wait() and Sleep() and in this case, to perform a synchronous object load. This simplifies the update somewhat, but to use the SynchronouslyLoadGameObjectByID() helper function the calling function must be running on a thread, so that it can wait for the asynchronous query to complete.		#The function is now declared as a [[TrainzScript_Keywords#thread\|thread]]. Script threads allow an object to use function calls like wait() and Sleep() and in this case, to perform a synchronous object load. This simplifies the update somewhat, but to use the SynchronouslyLoadGameObjectByID() helper function the calling function must be running on a thread, so that it can wait for the asynchronous query to complete.
	#The function no longer has a return code. This is necessary because the function is now asynchronous, meaning that the caller will continue execution after calling SetJunctionDirection(), before SetJunctionDirection() has a chance to run or complete.		#The function no longer has a return code. This is necessary because the function is now asynchronous, meaning that the caller will continue execution after calling SetJunctionDirection(), before SetJunctionDirection() has a chance to run or complete. If it is necessary for the caller to be notified of the success or failure of this call, then this is best achieved with message posts.

	It is worth noting that an object cannot have too many thread functions running on it at once, so too many calls to SetJunctionDirection() will result in a script exception with the error code ER_ThreadError.		It is worth noting that an object cannot have too many thread functions running on it at once, so too many calls to SetJunctionDirection() will result in a script exception with the error code ER_ThreadError.


	==Saving/Loading an ID==		==Saving/Loading an ID==

Pw3r at 04:37, 3 March 2022

2022-03-03T04:37:45Z

@@ Line 45: / Line 45: @@
   };
-==Saving/Loading an ID==
+==Getting an Object from an ID==
-==Getting an Object from an ID==
+==Saving/Loading an ID==
 ==Logging an ID==

Pw3r: Created page with "The following is an example of how to update a script which uses the obsolete script function GameObject.GetId(). It is intended to be read ..."

2022-03-03T04:03:52Z

Created page with "The following is an example of how to update a script which uses the obsolete script function GameObject.GetId(). It is intended to be read ..."

New page

The following is an example of how to update a script which uses the [[TrainzScript_Keywords#obsolete|obsolete]] script function GameObject.GetId(). It is intended to be read by content creators already familiar with [[TrainzScript]], but perhaps unfamiliar with the more modern concepts invovled with [[Asynchronous_Route_Streaming| Asynchronous Route Streaming]].

It is recommended readers first familiarise themselves with topics covered in the following pages:
* [[Asynchronous_Route_Streaming| Asynchronous Route Streaming]]
* [[Compatibility_mode|Compatibility Mode Setting]]
* [[HowTo/Upgrade_obsolete_script_functions|How to Upgrade Obsolete Script Functions]]

==Overview==
The script function GameObject.GetId() returns an integer ID which identifies an object within the script context. This ID is unique and constant for the life of the object only. When the specific object reference is released the ID becomes usable by other objects, and if the game is reloaded the world item represented by that GameObject (e.g. a Signal) will have some other ID.

This makes this ID of limited usefulness, and with the introduction of Route streaming they cannot be trusted and are considered obsolete. The modern replacement function is
public native GameObjectID GameObject.GetGameObjectID(void);

==Getting an Object ID==
The following example script shows a simple class which gets and stores objects integer ID.

class Example
{
int m_gameObjectID = -1;

public void SetObject(GameObject obj)
{
// Save the objects ID.
if (obj)
m_gameObjectID = obj.GetId();
else
m_gameObjectID = -1;
}
};

This class has a single member variable used to store the ID of an object, and a function which sets the object reference. To upgrade the script to support modern versions of Trainz, the integer ID must be replaced with a GameObjectID, and the GetId() call replaced with GetGameObjectID().

class Example
{
GameObjectID m_gameObjectID = null;

public void SetObject(GameObject obj)
{
// Save the objects ID.
if (obj)
m_gameObjectID = obj.GetGameObjectID();
else
m_gameObjectID = null;
}
};

==Saving/Loading an ID==

==Getting an Object from an ID==

==Logging an ID==