How to Use the UDS Interface

The information in this Wiki Page applies to TRS19 Platinum Edition, Trainz Plus and TRS22. Older versions of Trainz, including T:ANE and TRS19 (standard), do not have the UDS feature described in this document. A more detailed description of the UDS can be found on the Trainz Wiki Page Unified_Driver_Surveyor.

The UDS ( U nified  D river  S urveyor) Interface allows you to switch instantly between Surveyor and Driver modes without having to reload

The UDS is only found in TRS19 Platinum Edition, Trainz Plus and TRS22 It provides a method of quickly switching from Driver mode to Surveyor mode and back to Driver again without having to restart a running session after each switch After switching from Driver to Surveyor and editing you can save your edits before switching back into Driver but it is recommended that you save your work as a new session (unless you really do want to overwrite the original session) The virtual location of all consists is now stored as part of the Session even if the consists themselves are placed in the Route The Session Editor has a feature that allows you to reset any or all of the Session Rules before restarting a session

What is the UDS Interface?

UDS stands for  U nified  D river  S urveyor and is an "interface" or option built into TRS19 Platinum Edition, Trainz Plus and TRS22 that allows you to jump seamlessly from Driver into Surveyor and then back into Driver again to resume a session at the point where you left it. There is no need to restart a Driver session from the very beginning.

The Scenario: You are in Driver mode testing out a route and session when you discover a problem.

Previously (before the UDS) your only options would be to choose one of the following:- Options: ignore the problem (if possible) to continue the session in Driver and fix the problem later, OR immediately halt the session to fix the problem now

In both cases you would have to:-

Steps: To fix the problem terminate Driver and exit back to the Main Menu load the route into Surveyor and try to recall exactly where the problem is located locate and fix the problem save and exit Surveyor restart the session in Driver from the beginning (a bit tough if you were 2 hrs or more into the session)

The UDS interface allows you to switch, via a menu option, directly to Surveyor without having to stop and exit Driver mode first

When using the UDS you switch from Driver to Surveyor with the currently active Driver consist still as the focus and at the place it was located when you switched into Surveyor from Driver.

	All the Surveyor tools and options are available for you to use, including the Session Editor (more on that later)
	You use the Surveyor tools to fix the problem, such as deleting (as shown left), moving or adding a scenery object. You can then (if you wish) save the edited route and/or session (again there will be more on that later)
	You then switch back into Driver to continue driving the session with the problem fixed

Switching Modes

	Driver Mode to Surveyor
In TRS19 and TRS22 (standard) In Trainz Plus and TRS22PE Steps: To switch from Driver to Surveyor:- Open the  Tools Menu and select  Surveyor Mode  (in TRS19/22) or one of the two  Edit in Surveyor  options (in Trainz Plus and TRS22PE)

Warning: When you switch to Surveyor from Driver the Pause option (at the top of the Tools menu) will be automatically turned ON. If you turn this option OFF in Surveyor then any consists that were moving in Driver (and were then paused when you switched) will start moving again. This will almost certainly cause problems such as derailments. When Paused is checked ON it will also pause ALL animation effects (smoke, procedural track switch blades, animated scenery assets, sounds, etc).

Surveyor Mode to Driver

In TRS19 and TRS22 (standard) In Trainz Plus and TRS22PE Steps: To switch from Surveyor to Driver:- Open the  Tools Menu and select  Driver Mode  (in TRS19/22) or  Drive Session  (in Trainz Plus and TRS22PE) OR press  Ctrl  +  F2  If the Paused option is ON in Surveyor (the default condition unless you have turned it OFF) then the simulation will be paused and the Paused message will appear on the screen when you switch to Driver. Hit the  P  key to Unpause and resume the simulation.

The Undo command ( Ctrl  +  Z ) can be used in Surveyor but not in Driver.

Saving

Notes: An important change that has been introduced by the UDS is that train vehicle placement is now saved as part of the Session, even if those vehicles have been placed in Route Layers. It is strongly recommended that all consists be placed into a Session Layer and become part of a Session instead of the Route

Warning: If you decide to save your Surveyor edits and select the option to then you will OVERWRITE (a nicer way of saying DESTROY) your starting or original Session

Most of the problems users seem to be experiencing with the UDS, judging from the posts in the Trainz Forums, is when saving their edited Driver session after switching to Surveyor mode.

Notes: Using Driver Mode involves driving consists (either manually or through the AI) and activating session rules. This will change the session parameters Overwriting the Session will save the consist locations and Session Rules in their new positions/conditions

When you are in Driver Mode at least one of the consists will probably be moving. Some of the Session rules may have already been completed while others may still be running or waiting for events (e.g. triggers to be activated). If, after switching to Surveyor Mode, you then choose to save using the Overwrite existing session option then you will be replacing your original starting Session with a new one with the consists saved in their new positions and the Session rules saved in their new states. So when you later load and restart the Session things will not be the same as they were in the original or starting Session.

Unless you have a particular reason for overwriting the original Session then the recommended save options are:-

Option  Do Not Save the Session
	Steps: To save the Route only:- Left Click the checkbox  Do not save session  This will save the Route only, using its existing name and it will overwrite the original route. This will save any edits that you have made to the Route but not to the Session.

Option  Create a New Session
	Steps: To save the Route and a NEW Session:- Left Click the checkbox  Create new session  Enter a name for the new session This will save the Route using its existing name and it will overwrite the original route. It will also save the Session using the name you enter in the text box below the checkbox (Stage 3 in the example shown). The original Session will not be altered. This is useful when you want to test out changes to consists, industry settings, Rules, driver commands, etc but do not want to destroy the original Session.

If you have scenery assets (stationary objects) in a Session Layer that you will want to edit after switching from Driver to Surveyor and will need to save those edits but don't want to destroy your starting Session data, then:- Steps: move that Session Layer to the Route Layer Group before starting the Session in Driver. See Moving Layers for more details switch from Driver to Surveyor and edit when required. You can safely edit any Route Layer which now includes the moved Session layer after each edit you can save (Overwrite) the Route but do not save the Session. Use Option above When you have completed all the editing, saving and switching between Driver and Surveyor, then:- Steps: exit back to the Surveyor/Driver main screen reload the original Session (the saved Session edits will be in the Route that will be loaded along with the Session) move the layer from the Route Layer Group back to the Session Layer Group. See Moving Layers for more details save (Overwrite) both the Route and the Session

Resetting the Session Rules

After you switch from Driver Mode to Surveyor Mode it may be necessary to restart or reset some of the Session Rules

As mentioned above, when Driver Mode is running some of the Session rules may be completed while others may still be running or waiting for certain events (e.g. triggers to be activated). When you switch to Surveyor Mode these rules may be in a different state compared to what they were at the start of the Session. When you restart Driver Mode these rules may not be in a useful condition. The Session Editor built into all Trainz versions allows you to add, delete and modify the rules that will operate during a Session.

Information on the Session Editor can be found at:- Using the Session Editor

To open the Session Editor open the Edit menu and select  Edit Session 

	At the bottom of the Session Editor is a new button,  Restart ALL Rules . This will reset or restart ALL rules in the Session.
	Some rules, as shown in the screen shot above, have the label (complete was-complete) after the rule name. This indicates that the rule has already been completed. These rules can be individually restarted by a Left Click on the rule and selecting the  Reset  option from the pop up menu. This will change the rule status to (paused).
When the Driver Mode is selected again, all the reset or (paused) rules will be restarted.

Some Questions Answered

I have only edited assets that are in the Route layers but selecting Save always sets the option to "Overwrite exiting session" as the default. Why?

Many scenery assets actually have their properties stored in the Session, even when the assets themselves are in a Route layer. Editing the properties of these assets is considered to be a change to the Session. These include:-
	junction switches - the left/right switch direction is stored in the Session (but the switch default direction is stored in the Route)
	industries - the commodities and quantities loaded/unloaded are stored in the Session
	industry enabled wagons - the commodities and quantities carried are stored in the Session
	consist locations - this is stored in the Session (TRS19 Platinum Edition, Trainz Plus and TRS22 only
	named route objects - while the name is stored in the Route, adding or changing the name is treated as a change to the Session
If you have not altered any Session data or assets that have been placed in a session layer then you can ignore the request to save the Session as well as the Route. Changing the name of an asset, for example, does not alter any session data.

Interlocking Towers (including Enhanced Interlocking Towers) show paths as "not editable" after switching to Surveyor Mode. Why?

If you make the switch from Driver Mode to Surveyor Mode after an IT/EIT path has been activated (but not yet cleared or cancelled) then you will be unable to edit that path. In addition, you will not be able to add new paths to an IT/EIT that has an open active path.

Pierre (pguy), the creator of the EIT asset and associated rules, has a detailed description of this and some possible solutions in a Trainz Forum post at:- EITs and the UDS

Can I add new trains or replace existing trains after switching to Surveyor mode?

You can add additional trains and replace existing ones when in Surveyor mode but it is advised that:-
	the Paused option be set ON (the default condition) in Surveyor mode, and
	you may have to reset the Driver Setup Rule in the Session Editor particularly if you have added/edited driver commands to the new or altered consist

Does the UDS change how portals work?

This issue is now under investigation by N3V A train that is driven into a portal and later returned to the layout will be returned in the same layer as the portal and not in the trains originally assigned layer. Trains that are produced by a portal will be assigned to the same layer as the portal. This has  possibly always been the case with portals  but was probably unnoticed until the arrival of the UDS. It seems to have no other noticeable effect on trains. This could become an issue if you make the switch from Driver to Surveyor after a train has been returned to the layout from a portal. For example, if a train is originally in a Session Layer (as recommended for TRS19 Platinum Edition, Trainz Plus and TRS22) then it is part of a Session. If it is returned from a portal that is in a Route Layer then it will now be in the same Route Layer as the portal and it will be part of the Route, not part of the Session. If you save the Route after switching to Surveyor then the train will be saved in the Route and not in the Session. If this is an issue then the remedy is to open the property dialogue window of any wagon in the train after it has left the portal and change its assigned layer to the correct one. This will set all vehicles in that train to the same correct layer. Note: It is not recommended that you solve this by moving portals to a Session Layer if you have multiple Sessions because the portals will then only appear in the Session that contains the portals.

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Trainz Wiki

More Tutorials and Guides to Using Trainz How to Guides Driver Commands List Session Rules List (Alphabetical) with Parameters Session Rules List (Categories) With Parameters

Related Links Using the Session Editor

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This page was created by Trainz user pware in June 2021 and was last updated as shown below.

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