MSFS20 Change one Simvar when another changes

[P72endragon]

I'm trying to add some logic for an aircraft mod such that when one simvar is changed (triggered by the user toggling a switch for example), I can change the value of another simvar.

I've tried looking at the SDK docs, and am thinking I might need an `<InputEvent>` , but I'm really struggling with how to go about this. Please can anyone point me in the right direction?

 

[Anthony31]

I'd use an <Update> function simply because it is the easiest method.

Write the value of the simvar to an L:var.

If the simvar is different from the L:var change the value of the other simvar. Write the new value of the simvar to the L:var.

For example:

            <Update Frequency = "10">
                (A:IS USER SIM,bool)
                if{
                    (A:LIGHT PANEL:1,number)
                    if{
                        (A:LIGHT POTENTIOMETER:6,percent) (&gt;L:LIGHT_UV_LEFT_POTENTIOMETER,number)
                    }
                    els{
                        0 (&gt;L:LIGHT_UV_LEFT_POTENTIOMETER,number)
                    }
                    (A:LIGHT PANEL:2,number)
                    if{
                        (A:LIGHT POTENTIOMETER:7,percent) (&gt;L:LIGHT_UV_RIGHT_POTENTIOMETER,number)
                    }
                    els{
                        0 (&gt;L:LIGHT_UV_RIGHT_POTENTIOMETER,number)                  
                    }
                }              
            </Update>

This simple function checks the values of the Light Panel 1 and 2 (which can be switched by the user by various key commands, this covers all those commands in one simple step) and updates L:vars for light potentiometers for display within the cockpit without altering the actual light potentiometers values.

 

[P72endragon]

OK, so I'm trying this, to set SMOKE ENABLE the same as PROP DEICE SWITCH:

<Update Frequency = "10">
    (A:IS USER SIM,bool)
    if{
        (A:PROP DEICE SWITCH,bool) (&gt;A:SMOKE ENABLE,bool)
    }             
</Update>

I think the update block is running ok, but I don't think it's setting SMOKE ENABLE

Ultimately, I'm wanting to set SMOKE ENABLE from a joystick button. Since it isn't mappable in the standard controls, I'm basically trying to repurpose the prop deice control

 

[Anthony31]

Are you sure the update block is running? It needs to be attached to a component. Some people write with old style coding and I don't think the update block works in those situations. I only write in the new behavior code style where you need to include the update in a component (ie attached to a part of the model) otherwise it won't work.

First, I am sure you have a [SMOKESYSTEM] block in the systems.cfg.

This code uses the master battery and it includes a dummy L:var to check it is actually running (see the status in the Windows/Behaviors/Local variables screen).

            <Update Frequency = "10">

                    (L:dummy,number) 1 + (&gt;L:dummy,number)
                    (A:ELECTRICAL MASTER BATTERY,bool)
                    if{
                        (A:SMOKE ENABLE,bool) !
                        if{
                            (&gt;K:SMOKE_TOGGLE)
                        }
                    }
                    els{
                        (A:SMOKE ENABLE,bool)
                        if{
                            (&gt;K:SMOKE_TOGGLE)
                        }
                    }
            </Update>

This code also avoids any possible flooding issues. Because the smoke variables are ALL AIRCRAFT it is possible to send too much data down the multiplayer tube if you keep updating it. Only update these variables when they are different and that will ensure there is no flooding of data.

 

[P72endragon]

Sorry, yes, I did have that update code nested inside a component block

Ahh, it was the [SMOKESYSTEM] block that I was missing, that appears to be working now. Thank you very much for your help!