- We have to allow access without breaking old planes.
- There will be two distinct cases due to very different hardware.
One option (not really discussed in the RFC) is to do nothing at all. Basically I hit upon this during some routine refactoring of the shaders. The whole issue can be deferred indefinitely.
Why wait? Well, I don't believe that an incremental increase in the number of landing light halos is the future. Our end goal must be some kind of truly global illumination, hopefully without a fixed lighting budget. It may not make sense to add a bunch of complexity to the aircraft SDK only to have all of those limit become unnecessary cruft a short time later.
(I think I can hear the airport designers typing "why do the airplane designers get four lights and we get none? Give us a light or two!" My answer is: because of the fixed budget problem. We can allocate a fixed budget of lights to the user's aircraft because it is first in line - we know we either have the lights or we don't. As soon as we start putting global lights in the scenery, we have to deal with the case where we run out of global lights. For scenery I definitely want to wait on a scheme that isn't insanely resource limited!)
Programmers: yes - Dx10 hardware can do a hell of a lot more than 4 global lights. Heck - it can do a hell of a lot period! For example, it can do deferred rendering, or light pre-rendering. A true global lighting solution might not have anything to do with "let's add more global lights a few at a time."