Add support for variables in action/feedback inputs

[GeoDerp]

Describe the feature

Allow the ability to use dynamic variables in other modules.

Usecases

• For Timers from different modules
• For Modules that use the same (input/output) names
• Pretty much a good method to use input data from one module to output data for another by pressing one button.

Image Example

Example is using Qlab's Dynamic Variable (of time left in a video) to set the ProPresenter clock to the time remaining, and start it.

This is so the user doesn't have to fiddle around with the clock to get the precise time every time a Qlab video is playing (our Qlab videos all have different lengths)

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[krocheck]

This will have to be carefully thought through. An on-the-fly change to config isn't supported and would require an additional tracking layer and firing mechanism. Doable, but not simple.

[willosof]

Yeah, this is something we need to consider for the new design. Should be fairly easy to implement as long as we make a generic variable engine that everything needs to go through. :)

[willosof]

If it's a numeric input, we should support math as well :) floor($(inst:var)/2)+1 etc. Also, you should have the option to resolve the expression dynamic or "right now" :)

[mcondie65]

Being able to do math's would be fantastic. You could add a command in the advance to specific slide secion $(propresenter:total_slides)-$(propresenter:current_slide) which would allow you to skip to the next section in your ProPresnter playlist

[Julusian]

This needs to be done per module, and there is another task to look at supporting expressions in these fields #2345