Revised Inner Outer Inner mode for Classic mode

[igiannakas]

Ported the Arachne enhancements to inner-outer-inner wall ordering mode to Classic. It should behave better when multiple external perimeters are present in the same island and gracefully fall back to outer first to preserve wall consistency when inner-outer-inner wall ordering cannot be respected.

This brings feature parity between Arachne and Classic wall ordering for inner outer inner.

[igiannakas]

Test done, benchy looks good!

[Eldenroot]

Nice! thx!

[SoftFever]

@igiannakas
Do you have screenshot to demonstrate the improvement for the scenario you mentioned?

[igiannakas]

Yeap:
Before:
Middle perimeter drawn before outer

After:
Outer perimeter drawn correctly before neighbouring inner perimeter

Before:
Middle perimeter drawn before outer

After:
Outer perimeter drawn correctly before neighbouring inner perimeter

[igiannakas]

The above is the same issue that Arachne used to have before the revisions in the inner/outer/inner ordering mode -> basically middle perimeters are on occasion drawn before the outer perimeter when there are multiple external perimeters on the same island.

The revision enforces middle perimeters to be drawn after the external and if that is not possible it falls back to drawing the external perimeter first to minimise surface artefacts caused by the middle perimeter pushing out on the external ones if drawn first.

Basically porting the below to classic mode and the fixes that came from those:
#2276
#1861
#1352

[SoftFever]

Yeap: Before: Middle perimeter drawn before outer

After: Outer perimeter drawn correctly before neighbouring inner perimeter

Before: Middle perimeter drawn before outer

After: Outer perimeter drawn correctly before neighbouring inner perimeter

Awesome!
Thank you very much

[SoftFever]

Looks good.
Thank you