Drag reduction not taking tinker size into account for the wings

@PhilipTarpley the feet may be related to another issue I guess

From what I gathered from @AndrewGarrison (he wrote the drag code), the fuel tank wasn't actually occluding the fin, it just caused the drag visualization camera to back up (which it probably should not have, since the tank was disconnected). The fact that it backed up caused some drag calculation weights to change by small amounts and resulted in a minor change in drag...causing the drag to increase by a bit, and go above the occlusion threshold. This was such a slight change as to not normally cause a change in flight performance had it not caused the value to go above the threshold...and allowed wing physics to remain enabled with the fuselage.
 
TLDR; Removing the fuse resulted in a slightly lower drag for the fin due to the drag camera, which resulted in the fin's wing physics being disabled, because it was considered occluded.
 
I have not looked into the impacts of the feet that you're referring to.

@PhilipTarpley the thing is that now the scaled wings are occluded by parts that shouldn't really occlude them (the feet or the unconnected tank), I thought the occlusion was calculated for the original collisions of the wing and not the collisions of the scaled wing

@pedro16797 We were discussing that today, but we're not sure what to do about it. I had initially advocated having occlusion refect the non-scaled version of the wing (like I think you're suggesting). But, this could easily make some part-scaled wings stick out of an enclosure that they appear to be inside, even though the visual for the wing is wholly inside the enclosure...it would be impacting flight performance while appearing as though it should be unaffected by any airflow.
 
This could be a significant issue for people trying to transport contraptions w/part-scaled wings inside a fairing, for example.

@PhilipTarpley what about renaming it to reflect the issue with the occlusion being calculated without taking tinker size into account?

@pedro16797 Actually, I think we may keep this one around and perhaps re-word it to highlight the issue w/the wheels.

@PhilipTarpley feel free to mark this report as rejected and thanks for all the help

@pedro16797 Yeah, we'll certainly have to get to the bottom of what is happening w/the wheels...don't know exactly when that will be worked, though. Also, good idea disabling drag on the stick to get the fin working.

@PhilipTarpley is there any other way to fix the issue with the wheels? I like the effect of the witch hovering over the ground

@PhilipTarpley I'll try that, btw, no drag in the stick and all the flight control problems are solved

@pedro16797 "Another thing I noticed yesterday before going to bed is that in the mobile version it breaks instantly when launching."
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I wonder if this isn't related to the strange issue w/the wheels...try disabling suspension on the wheels and see if it behaves better.

@AndrewGarrison thanks! I love how it flies and bringing down the pitch it hovers great, I'll be using her in the future a lot for custom planets development

Fun fact: The foot also occludes the wing, I thought about drag being the issue and that's why the foot has drag disabled, but I thought unattached parts didn't affect to pre-launch drag calculations, thank's for all the info, I'll try to fix it now :)

Sorry, it was part ID 80, not 81.

So one way to fix this is to make the wing stick out a bit more so it will be visible to the camera that renders for the drag calculator. Then you can check the <Drag area="..." /> to ensure that its total area is above 0.001.

Also, I forgot to mention, we all think your craft is awesome! It's pure witchcraft!

Okay, Philip was able to track down the issue to the fin with part ID 81. The drag calculator calculates the drag slightly differently depending on if the fuel tank is there or not. The fin's drag area is calculated as something like 0.0011, but without the tank it's calculated at around 0.0008. Normally a 0.0003 m2 difference in area is not going to make any noticeable difference, however, that difference is just enough to put it below the threshold for being flagged as occluded. When a wing is occluded its physics is disabled and that's why it behaves differently.

Edit: Sorry it was part ID 80, not 81.

@AndrewGarrison the thing is that with the unconnected fuselage there I have no issue at all, but after removing it then all the problems show up

Another thing I noticed yesterday before going to bed is that in the mobile version it breaks instantly when launching

This craft has some interesting problems. We were all looking into this one a bit today. I could not even take off with the craft on my work PC, but it did fine on my home PC. It turns out the wheels work a bit differently depending on the rotation of Droo. It can cause an issue where the craft appeared to almost be stuck to the runway. Disabling suspension on the wheels helped with that. Also, the craft was incredibly unstable because of the zero mass scales and resulting in low inertia tensors. Philip noticed that increasing the stability modifiers improved that quite a bit.