[2.8pre-1244] Fade is applied incorrectly under a 3D floor.

[MaxED]

Looks like that Fade property is applied incorrectly when a map has OutsideFog property set and a player is under a 3d floor in a sector with F_SKY as a ceiling texture.

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Code: Select all

map MAP01 "Foggy Fial" 
{
    Sky1 = "SKY1"
    OutsideFog = "FF 00 00"
    Fade = "00 00 FF"
}

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Outside of the 3d floor:

Under the 3d floor:

EDIT: updated title, description, screenshots and example wad.

[Graf Zahl]

ZDoom doesn't even USE these properties! I'll have to check what goes on here...

[MaxED]

Heh. Yes, now I noticed that it complains about unknown MAPINFO properties, but the effect is definitely there:

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Outside...

...and under

[Enjay]

Is this what was causing the patchy fog in the tunnel in your Exhumed/Powerslave mod?

[MaxED]

Yes.

[Ozymandias81]

Done. Added "disable light effects" to 3d tagged sector + another sector with "transfer brightness levels" below 3d sector.

[Graf Zahl]

This is not a bug as such. The rules are rather simple and followed precisely here:

1. The engine cannot easily separate fog above and below a 3D-floor. The problem is not so much the actual rendering of the fog but the boundaries.
2. A sector's fade gets transferred to a blend when used in conjunction with 3D-floors.
3. Mapinfo fog is nothing more than a cheap script surrogate that sets fog for all sectors (or in case of 'outsidefog' all sectors with a sky ceiling or the 'outside' sector type.) After being set, the fog in such a sector is indistinguishable from fog set with Sector_SetFade.

So the result here obviously is that the control sector gets assigned blue fog which then gets transferred to a blend for the 3D floor. It's a classic case of mutually incompatible features.

[Ozymandias81]

This is not a bug as such. The rules are rather simple and followed precisely here:

1. The engine cannot easily separate fog above and below a 3D-floor. The problem is not so much the actual rendering of the fog but the boundaries.
2. A sector's fade gets transferred to a blend when used in conjunction with 3D-floors.
3. Mapinfo fog is nothing more than a cheap script surrogate that sets fog for all sectors (or in case of 'outsidefog' all sectors with a sky ceiling or the 'outside' sector type.) After being set, the fog in such a sector is indistinguishable from fog set with Sector_SetFade.

So the result here obviously is that the control sector gets assigned blue fog which then gets transferred to a blend for the 3D floor. It's a classic case of mutually incompatible features.

So this will be very hard to fix on future versions of GZDoom, I think.