Force invert-mouse-wheel = true

[PlayeRom]

FG gives us a choice if we want the mouse wheel to work in reverse (menu "File" -> "Mouse Configuration" -> "Reverse mouse wheel direction" which sets the /sim/mouse/invert-mouse-wheel property). So why in Cessna we are forced to use reverse mouse wheel? I mean instruction in the c172p-main.xml file:

<!-- Fix scrolling direction of knobs -->.
<mouse>
    <invert-mouse-wheel type="bool">true</invert-mouse-wheel>.
</mouse>

This instruction causes my autosave file to be overwritten and I have to uncheck "Reverse mouse wheel direction" every time (I prefere without reverse). I also didn't noticed any problem with knobs after removing this instruction at all.

[wlbragg]

I don't understand why this changes anything to do with autosave, can you explain? As far as why invert is hardcoded, I have no idea. You would have to dig through the commit history and see if you can find any comments on it.

[wlbragg]

@wkitty42 your pretty good at searching stuff, do you know how to run a keyword search over commit history?

[dany93]

This is an endless issue.

• As for rotating a knob, a potentiometer, or the magneto key, people are divided (CW or CCW vs wheel scrolling).
• As for a value, many people prefer that it increases when they "push" the scroll wheel.

These two above are often contradictory.

• In its current setting, the mouse scrolling is counter intuitive for the throttle, mixture, flap lever. Also (IMO) the elevator trim (nose up / down).

[wlbragg]

@dany93
"Counter intuitive" are you of the opinion that the hardcoded invert is responsible for the default direction being counter intuitive? Does anyone know how c172 rotation defaults compare to other aircraft? I'll have to fire FG up and see what the knobs feel like. But from my minds perspective I think scroll forward should increase any knob and scroll back to decrease. Would this be most people's opinions?

[dany93]

@wlbragg

"Counter intuitive" are you of the opinion that the hardcoded invert is responsible for the default direction being counter intuitive?

It depends on what you are calling "the default direction" (= current direction?) and "the "hardcoded invert" (= <invert-mouse-wheel type="bool">true</invert-mouse-wheel> ?)
But for example, scrolling forward makes the throttle or mixture levers moving backwards. This is obviously counter intuitive.
Also, scrolling forward making the flap lever moving downwards is counter intuitive.

@wlbragg wrote

I think scroll forward should increase any knob and scroll back to decrease. Would this be most people's opinions?

@dany93 wrote

As for a value, many people prefer that it increases when they "push" the scroll wheel.

Thus, I agree admit.

[PlayeRom]

@wlbragg I honestly don't know, but it does :) It looks like first the config from autoseave is loaded and then the one from the aircraft, which overwrites the autosave.

@dany93 Maybe I do not understand something, but I think it makes no sense to talk about who prefers what, because as I wrote in the FG options you can choose what you prefer, what is saved in the autosave, only I do not understand why the C172P forces its own setting over autosave.

In my case, invert-mouse-wheel = false means that when I turn the wheel forward, the throttle increases the thrust. Therefore I prefer this behavior. Unfortunately the aircraft always sets it to true. I tested with 2020.3.13 and next on Linux Mint.

My workaround it's add --prop:/sim/mouse/invert-mouse-wheel=false to the command line. So out comes the fun of who gets to overwrite who last :)

[PlayeRom]

It was added with this commit: 1d92ca5

[wkitty42]

On 5/10/22 1:26 PM, dany93 wrote: @wlbragg <https://github.com/wlbragg> "Counter intuitive" are you of the opinion that the hardcoded invert is responsible for the default direction being counter intuitive? It depends on what you are calling "the default direction" (= current direction?) and "the "hardcoded invert" (= |<invert-mouse-wheel type="bool">true</invert-mouse-wheel>| ?) But for example, scrolling forward makes the throttle or mixture levers moving backwards. This is obviously counter intuitive. Also, scrolling forward making the flap lever moving downwards is counter intuitive.

FWIW: i understand the problem and it is a tricky one to handle...

@wlbragg <https://github.com/wlbragg> wrote I think scroll forward should increase any knob and scroll back to decrease. Would this be most people's opinions? @dany93 <https://github.com/dany93> wrote As for a value, many people prefer that it increases when they "push" the scroll wheel. Thus, I agree.

now, consider this... you're looking at a document... line 1 is at the top and line 100 is at the bottom... which way do you scroll your mouse wheel to move down to line 100? you "pull" it toward you thus making the line numbers get larger... if you push the wheel, the line numbers get smaller... same for web pages... pushing the wheel takes you to the top of the page whereas pulling the wheel takes you down the page... in regards to radio knobs, if i push the wheel, i expect the frequency numbers to get smaller and pulling the wheel makes them get larger... this is in the same way that the line numbers in a document get larger or smaller... in regards to the throttle, flaps and other similar levers, i expect to push the wheel to make the levers/slides move away from me and pulling the wheel would bring them back toward me... it sounds like the code should be multiplying by -1 in some cases (levers and slides?) while not multiplying in others (turning the knobs)... this way, pushing the wheel would make the radio knobs turn CCW while also pushing the wheel would make the lever/slider move away from you... i just don't know which ones need to be multiplied by -1 and which do not... if we even have that kind of control in the craft's code...

[wlbragg]

@PlayeRom
@dany93 commented on the popularity of scroll directions because I asked about it. I understand what your saying about it not really mattering as it is supposed to be offered as a choice by FlightGear's main menu. I don't know why it is hardcoded other than to assume it was done so to make radio dials that were also part of that commit work in a certain way.
@wkitty42 I guess I need to get in the c172 and see for myself how all the knobs, dials and sliders behave compared to your reasoning and analogy.
One thing that might be a fix is to make the invert option available in the c172p menu. Although that seems redundant. I agree that an aircraft should avoid overriding a setting that is typically a choice in the main FG settings.

[dany93]

My impression is that merely deleting or commenting in c172p-set.xml

<mouse>
    <invert-mouse-wheel type="bool">true</invert-mouse-wheel>.
</mouse>

would solve most of these issues (except for the subjective preferences for rotating knobs...).

Why setting it to "false" (at the risk of overwriting a user's simulator setting)?

[dany93]

@PlayeRom wrote

@dany93 Maybe I do not understand something, but I think it makes no sense to talk about who prefers what, because as I wrote in the FG options you can choose what you prefer

It does make sense because you invert everything. Which cannot match everyone's preference.
Thus, the endless issue.

[dany93]

See this message from @onox.
And the rest of the conversation in the same issue.
And Pull Request #1332 (particularly the first message).
Notice that Pull Request #1332, commit 63467c62e612 sets
<invert-mouse-wheel type="bool">false</invert-mouse-wheel>
(although I rather suggest deleting this piece of code).