Custom Simulation Variables

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1

Hi,

I am working on a custom aircraft. Is there a way to create a “Custom Simulation Variable” in the aircraft’s config files so that this variable can be read and written to/from Simconnect? This variable can and should exist only if the user has this aircraft selected.

Or any light on the subject where to create this custom variable?

Many thanks.

2

Hello,
You can create local variables called L:vars, they will be readable/writeable throughout the session.

for example (L:MyVariable,number) or (L:MyBool,bool)

they are readable and writeable in XML and in JS , and should be possible through simconnect.

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3

Thanks Marwan,

based on the name “local variables” instead of custom variables I was able to find something I can use. Looks like I can use the Gauge API in the SDK to register local variables.

Is there any other way to create new local variables (LVARS)? Like in a .cfg or .XML file?

4

Hi ,
You can update and set local variables through an update loop or button clicks of a model.xml of any aircraft.

I will share some examples once i get to my PC.

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5

Hello,
So you will find below example of the 2 ways you can set a variable through the modelbehaviour xml file of an aircraft, for example my interior model behaviour file is called HA420_interior.xml , and inside it I can have the codes of the following examples.

Setting and reading variable in the update loop of the model:

<Behaviors>
    	<Component ID="Update">
    		<UseTemplate Name="ASOBO_GT_Update">
    			<FREQUENCY>30</FREQUENCY>
    			<UPDATE_CODE>
    //your code goes here for example:
    //=============================exampe 1=========================================
    20 (>L:MyVairable,number)  //sets the value of the variable (L:MyVairable,number)  to 20,
    //=============================exampe 2=========================================
    (L:MyVariable, number) 30 + (>L:MyVariable, number)   // adds 30 to the variable, value is now 50. notice the format is Reverse polish notation (RPN);
    //=============================exampe 3=========================================
    if (A:Fuel tank center quantity,gallons) (L:MyVariable, number) > if{ 1 (>L:MyBool,bool) }  els{ 0 (L:MyBool) }      // reads simulation variable fuel tank quantity , compares it (L:MyVariable,number) , if greater set (L:MyBool,bool) to true (value of 1) else will set to false (value of 0)

    			</UPDATE_CODE>
    		</UseTemplate>
    	</Component>

And this is an example of setting a local variable through cockpit interraction:

 <Behaviors>
    <Component ID="HA420_BATTERY_MASTER" Node="HA420_BATTERY_MASTER">
    	<UseTemplate Name="ASOBO_GT_Push_Button">
    			<NODE_ID>HA420_BATTERY_MASTER</NODE_ID>
    			<ANIM_NAME>HA420_BATTERY_MASTER</ANIM_NAME> 
    			<LEFT_SINGLE_CODE>
    						70 (&gt;L:BM Pushed,bool) // here on button press, the local variable (BM pushed,bool) will be set to 70, notice the use of " &gt;" this is interchangeable with ">" , both can be used.
    			</LEFT_SINGLE_CODE>
    			<TOOLTIPID>%((A:ELECTRICAL MASTER BATTERY, Bool))%{if}TT:COCKPIT.TOOLTIPS.MASTER_SWITCH_BAT_ON%{else}TT:COCKPIT.TOOLTIPS.MASTER_SWITCH_BAT_OFF%{end}</TOOLTIPID>
    			<WWISE_EVENT_1>battery_switch_on</WWISE_EVENT_1> 
    			<WWISE_EVENT_2>battery_switch_off</WWISE_EVENT_2>
    	
    	</UseTemplate>
    	
    	
    	
    </Component>

 </Behaviors>

by the way, there is no need to declare L:vars, once they are mentioned in a code they are created automatically , if no value is assigned to them they will have a default value of 0.

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6

Many thanks. That is perfect. This is what I have been looking for.

Really appreciate the example and help. :grinning:

Cheers
Fritz

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7

Glad I can help, feel free to ask any time.

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8

Are Lvars accessible through SimConnect ?

9

No they are not. You found something wrong on the internet.

10

Simconnect - NO
WASM - Yes

You can create a WASM module in Visual Studio and that gives you access to the LVARS.

Look at this code. It reads the LVARS in WASM and creates a custom event that you can then read in SimConnect. Haven’t tried it myself, but it is demonstrating a way of getting LVARS into SimConnect.

and

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