What is the absolute fastest way to add 1 to a variable while retaining framerate independence?

I’d just add n*dt and int() the value every time you access it.

I guess if you don’t need to access the variable very often you could just do this right before you access the value:

Global number starttime=0

Some condition

— add (time-starttime)*dt to variable

— set starttime to time

— do something with the variable

I doubt either would be noticeably faster.

Yeah I guess I'd have to, huh? Then just compare >= for any it skipped over for values greater than 1.

I thought an expression that at 30 fps adds 2, or 120fps adds 0.5, and so on, would be more accurate..but fps is never perfectly stable, would result in floats, and is functionally similar to dt anyway so...blah.

I mean you could do an expression like:

Set var to int(time*30)

To get one to be added 30 times in a second. Then it would be just integers.

In general the expression would be

int((time-starttime)*rate)

Do you want something to happen every time the car changes by one? I don’t think I follow why you’d need >=. I mean you could do something like the following to do something every time it changes by 1. Depending on what you want to happen you may have to do some interpolation if say you wanted to shoot bullets and they need to be spaced correctly.

Global number prevVar=0

Global number var=0

Every tick

— set prevVar to var

— set var to int(time*30)

Repeat var-prevVar times

— do something

I thought an expression that at 30 fps adds 2, or 120fps adds 0.5, and so on

If you want to basically add 1 to a variable every tick, but take in to account framerate independence, then that's 60 * dt. It will do exactly what you said: every tick it will add 2 at 30 FPS, 1 at 60 FPS, 0.5 at 120 FPS, etc.