Sun halo in different starfield rendering modes

[375gnu]

Both in 1.6 and 1.7 versions. Depending on starfield's style a sun halo either present or not:
No halo with scaled disks:

Halo present with points and fuzzy points:

1.7 had the same behaviour before #533. Now it has less bright halo in «points» and «fuzzy points» modes.

Quite interesting is that Alexell's version didn't have this bug. UPD: when vp&fp programs doesn't present, so older strarfied with quads is in use.

[SevenSpheres]

solution: implement #2

[SevenSpheres]

1.7 had the same behaviour before #533. Now it has less bright halo in «points» and «fuzzy points» modes.

I can confirm this; in fact I've mentioned it in #523 and #589, and made a duplicate issue for it at #596 (sorry!) Still agreed with my comment above. I'll post my screenshots again here.

Sun in older 1.7 build, with star style set to fuzzy points:

Sun in newer 1.7 build, with star style set to fuzzy points:

[SevenSpheres]

This apparently affects Celestia Origin's rogue planet addon as well (BlendTexture seems to be broken):

@375gnu I think this should be labeled "high priority".

[375gnu]

These visual glitches are related, but are not the same.