Making fog look good in GZDoom.

[Deathmatcher]

I took the GZDoom 1.50 release as an incentive to see how my current project (made for ZDoom) would look like under the GL renderer. Surprisingly good, but some of my maps use outsidefog. In ZDoom, I already had the issue that the transition from foggy to non-foggy (interior) sectors looked very weird, because the seperating linedef would appear as a solid wall of fog. I resolved that issue by applying higher light levels to certain sectors. Specifically, I applied light level 255 to "roof light" sectors within interior rooms to virtually remove the fog effect for these sectors.

In GZDoom, however, I have the same issue again. I understand it that the GL renderer does not attenuate fog level with increasing light level, like the software renderer does? If this is correct, I don't see any level design means to "de-uglify" the sectors in question. I looked into http://zdoom.org/wiki/MAPINFO_options_f ... L_renderer but this didn't really help to resolve my problem.

Is there any technique (mapinfo command usage I'm not aware of or level design trick) that removes the ugly "walls of fog" when going from a fog sector to a non-fog sector? Is there any way to disable fog in a certain sector entirely?

[Graf Zahl]

Don't use light level 255. Use something a bit less. 255 is fullbright which will activate the fog boundaries.

[Deathmatcher]

This did not resolve the problem. I set the light level just 10 units above the surrounding interior sector. It still looks ugly, as you can see on the screenshot.

[Graf Zahl]

Please PM me the map. That shouldn't happen.

[Caligari87]

I, too would like some information on making fog like this look good, considering that my next project will make a lot of use of it.

[Graf Zahl]

With the test WAD ZDoom produced a boundary between the 176 sector and the rest but not the 255 sector. This is to be expected because in the software renderer 255 means fullbright, i.e. no fog. That particular check was missing in GZDoom.

But what you failed to mention here was that you were talking about foggy sectors in a non-foggy area. I have the strange feeling that your entire setup is not going to work well, considering that your skylights were fog-less to begin with - which is why they had no fog boundaries in ZDoom.

[Salad Viking]

Graf is right. What you should do is use some "fake fog," i.e. use a translucent white midtexture that fades out as it extends down. A lot of wads use this trick.

[Graf Zahl]

I think all problems shown by this WAD are fixed now. No idea if it's going to help you though.

[Deathmatcher]

I'm not really sure what to make of this now. Do you mean that you added a 255 = fullbright check to the GZDoom code base, which will be in the next release?

Apart from that: The foggy sectors in a non-foggy area are just one of the two issues. The other issue is that the same fog boundaries show up when being in a foggy area and looking at the facade of a building, which has a non-foggy sector at its fringe. I think this is more easily fixed by adding the 87 sector special to the fringe sector, though..

[Graf Zahl]

That problem is present in ZDoom, too - and sector type 87 is meant precisely for such situations.

[Deathmatcher]

Good to know, thanks.
Sorry for asking again but did you add a fullbright fix for the next GZDoom release? I'm not sure about that.

[Gez]

http://mancubus.net/svn/gzdoom/?op=revi ... 90&peg=890

[Deathmatcher]

Awesome. Thanks, both of you.

[The Ultimate DooMer]

I'm going to bump this, because I believe this change has caused a negative effect:

Check these screens, the first two with r880, the last two with r892.

http://img841.imageshack.us/i/880over.png/
http://img39.imageshack.us/i/880under.png/
http://img338.imageshack.us/i/892over.png/
http://img444.imageshack.us/i/892under.png/

Note that 892 is screwed up compared to 880. Given the use of Sector_SetFade in the control sector to produce the Boom-esque coloured milkiness under the water, one can assume that it's something to do with the fog changes in 890.

[Graf Zahl]

I can't deduce anything from your screenshots. Fact is, the old calculations were flat out wrong.