Correct odd layer GUI description

[vovodroid]

Currently every second layer for "on odd layer" options is checked as layer_id % 2 == 1. Though from mathematics POV it's correct, but in GUI first layer is one and not zero, thus actually option is applied for even layers.

I guess this is SuperSlicer legacy, and this PR fix this confusing description in GUI.

[kisslorand]

Isn't the first layer numbered "0"?

[vovodroid]

In code yes, but in GUI first layer is "1".

[vovodroid]

[vovodroid]

Another option - call it "every other layer", like here

[SoftFever]

Nice catch!
Can we change the code logic to make it align with the UI, but leave the text/description unchanged?
e.g.
change code from layer_id % 2 == 1; to layer_id % 2 == 0;

[vovodroid]

Sure we can, but layer_id % 2 == 0 includes first (zero) layer, thus demanding special handling. Also is change perimeters for all existing projects. So I guess change description is much better.

[SoftFever]

The catch with changing user facing text is that it will invalidate all existing translations

[vovodroid]

Translations could be updated, it's updated on GUI changes anyway.
Also expressions layer_id % 2 == 0 will affect first layer, and layer_id > 0 && layer_id % 2 == 0 will skip two first layers, causing inconsistency in behavior.

[SoftFever]

Translations could be updated, it's updated on GUI changes anyway. Also expressions layer_id % 2 == 0 will affect first layer, and layer_id > 0 && layer_id % 2 == 0 will skip two first layers, causing inconsistency in behavior.

Good point :)

[SoftFever]

LGTM