LINDA GUI required?

[rX 1]

Hi,

I see in the Q&A post that Linda GUI is required in FSX for Joystick inputs to work. Does that apply for P3Dv5 or such? I'm asking because it seems strange that:

1. The GUI has this note next to "Start GUI with Sim": Note: LINDA core code is started by entry FSUIPC.ini
2. The setting "Start GUI with Sim" is disabled by default.
3. I have not been able to make it work without starting LINDA GUI manually or setting the "Start GUI with Sim" to on.

Is this by design? Does the GUI really need to run for normal use (after configuration)?

Thanks,

Eric

Edited August 30, 2020 by rX

[ScotFlieger 280]

Good question. The LINDA LUA is used to run all functions both core and aircraft modules. It is loaded when FSUIPC (any version) starts and calls the ipcReady.lua and Linda.lua files. It can run independently of the LINDA GUI. 

The issue comes when you start or change the aircraft in the Flt Sim, need to reload the LUA ‘engine’ for any reason or wish to reassign any buttons (axes are programmed and controlled by Sim or FSUIPC). For this you need to run the GUI which ensures LINDA is sync-ed to the Flt Sim and detects aircraft changes. Once LINDA is up and running the GUI should remain running.

The ‘Run with Flt Sim’ option is used to add or remove the fsuipcX.ini entry to start the GUI when the Flt Sim is first run. Because of my development and testing work I tend to start, stop and change the GUI (Linda.exe) separately from the Flt Sim I am running.

I hope that helps.

Edited August 31, 2020 by ScotFlieger
Corrected erroneous statement

[rX 1]

Hi Andrew,

Thank you for the prompt and thorough explanation. 

I feel I am still missing something, or it's somehow broken for me. I understand this should work: provided everything is setup and working correctly, (and not switching aircraft), closing (not minimizing) the GUI should not disable Linda (for LINDA's Joystick button mapped inputs for Aircraft Modules <FSL A320>) and it should continue working.

If so, that is not working for some reason. It works perfectly fine with the GUI open but as soon as I close it it stops functioning. As I close the GUI FSUIPC prints to the logs 

863703 LUA.0: LINDA:: [S] LVars watching list cleared...

But that might be be just for the VRInsight outputs which I am not using.

I also tried assigning a keypress to LUA LINDA and LUA ipcReady and that displays messages that LINDA is starting, but it's not functional. When I start the GUI it shows that LINDA is restarting so it's not joining the existing session (again, not sure what is expected).

 

NB: this is not a critical issue. With GUI everything is functioning perfectly but due to my obsession to having as few binaries running in the background and my understanding that LINDA.exe is not in fact necessary during runtime, I'd like to achieve it if possible by design. 

[ScotFlieger 280]

I apologise for an error in my explanation. The GUI provides the means by which button presses are detected and communicates this to the LUA code. It does need to be running at all times for LINDA to work.

The GUI has a minimal load on any CPU time or memory. It can be minimised when not required.

As I mentioned, the GUI must be running for start up as it is used as the communications channel between the LUA and FSUIPC and vice versa. It is the GUI that determines the loaded aircraft and there are some functions that also rely on this communication. This is especially the case with the FSLabs module where we have had to employ mouse macros. The GUI is also active when Saitek Panels are used and the checkbox ticked.

The clearing of the watch Lvars is part of the LINDA tracer functionality that we use for development. If LINDA is not running in developer/fault diagnosis mode no extra processing is taking place. 

The LINDA startup sequences is as follows:

• The Flt Sim starts FSUIPC.dll.
• FSUIPC when ready calls ipcReady.lua.
• FSUIPC also starts the GUI depending on the fsuipcX.ini [programs] entry.
• ipcReady.lua contains one statement that calls linda.lua.
• linda.lua sets up LINDA initialisation, load some settings and calls init.lua.
• init.lua completes the initialisation, loads libraries, configuration, specific device modules and assignment, and launches the main LUA code.
• LUA then awaits the GUI detection of the aircraft and any reloads.
• LUA also polls for any buttons presses detected by the GUI and calls the assigned function.

My advice is to keep the GUI running and minimised for efficient operation.

[rX 1]

Hi Andrew,

It's clear [mostly] now. LINDA GUI reads HID and then calls interprocess to FSUIPC with Linda LUA running. Without the GUI not only button presses aren't detected but also switches the assignments/profiles based on loaded aircraft. 

The confusion came from this below which still reads as though Linda will be functional if after startup is completed the GUI is closed - its current form still confuses me 🙂 Maybe it meant to say "minimized"?

13 hours ago, ScotFlieger said:

ERROR incorrect statement. Once LINDA is up and running the GUI can be closed.

Anyway, no need to waste any more time on this and I will just use "Start GUI with Sim" and leave it running minimized while in the sim. 

Thank you!