Need help with Layer trait's "Follow Expression" feature

Module Design
1

Please correct me if I am wrong:

Ok so I grasp that what you put in the “Follow Expression” feature should return a numeric value ( yes ? what if you return a boolean or string ? ). This value will then be used as the active layer number. So if my expression returns 7 then layer 7 becomes active ( yes ? ).

But what does the “Level 1 = userinput” bit do ? Does the expression start counting from the layer you specify there ? e.g. if I put “Level 1 = 3” and my expression returns 4 then 6 becomes the active layer ( because Layer 3 is active on 1, Layer 4 is active on 2, Layer 5 is active on 3, Layer 6 is active on 4, etc ) ? Have I got that right ?

2

If “Level 1” is set to 1 (the default), then the first image in your list will be used when the expression evaluates to 1, the second image in your list will be used when it evaluates to 2, and so forth.

If “Level 1” is set to 0, then the first image in your list is used when the expression evaluates to 0, the second one when 1, etc.

You can set other values, though those are likely to be the two most useful. So normally you just leave Level 1 set to 1 and it “does what you’d expect it to do”.

3

Thanks Cattlesquat.

So essentially set “Level 1=” to whatever the lowest number your expression can evaluate to.