Where are these additional visplanes coming from?

Okay, I have 45 sectors in this arena but I'm still getting VPOs

No idea what's happening here. Help?

You can download the map here to test it out. I use ZenNode as my node builder.

Do you have any light specials in that room?  I've run into problems before where flashing or glowing lights will cause the visplanes to spike (especially if there are a lot of them).

*edit*

Just took a look at the map.  You can try removing those light specials and see if that helps.

FWIW, a room with only 2 sectors can cause a visplane overflow.

Okay so here's a screenshot showing the Nodes viewer mode. From what I gather from your link, there are too many sub sectors in this map & that's what's causing the Visplane overflows?

1 hour ago, Mechadon said:

Do you have any light specials in that room?  I've run into problems before where flashing or glowing lights will cause the visplanes to spike (especially if there are a lot of them).

 

*edit*

 

Just took a look at the map.  You can try removing those light specials and see if that helps.

I've tried—still hitting 136 visplanes.

Thanks for the link Ling.

See if you can't obscure a floor detail with a raised sector (or ceiling detail with a lowered sector, conversely). Sometimes, especially if you're running close to the visplane limit, little changes like that can make more difference than you'd imagine. Height changes in general are a godsend for this; until you start breaking seg limits and getting HOMs in the distance, but that's a different kettle of fish.

If I ever get the urge to write another "Doom XYZ Bible" thread I think it will be about the theory and practice of visplanes. 

The "C" shaped ceil5_1 floor thingies eat up about 30 visplanes

5 hours ago, Linguica said:

FWIW, a room with only 2 sectors can cause a visplane overflow.

Indeed, there was a VPO in one of my demos for 2sectors (noticed by Gusta), so it doesn't even need to be a very contrived situation. The demo in question is 2s05-102.lmp (UV Max on map05), which can be found here.

Try BSP as your nodebuilder, it has some visplane optimization or whatever.

Different sector heights and different sector brightness's in view can certainly increase the chance of a Visplane Overflow. Remember a different light level or height will add to the subsector count.

Sectors within sectors really multiply the VPOs. So all those borders around the teleports are probably the problem.

I think mouldy nailed it.

Yeah deleting those sectors has certainly solved my problem. Didn't want to do it, but alas, Vanilla Doom limits are not a mistress one can reason with.

Been there.   I was thinking about this room and an alternate way to fix it; what if you spread out the room by 50%?  (Use Wadauthor's Scale sector function, then move everything around). That might give you enough distance between the offending areas.   

^ How "enough distance"? Enough to achieve what? I'm not aware that visplane count would be affected by view distance.

30 minutes ago, joepallai said:

I was thinking about this room and an alternate way to fix it; what if you spread out the room by 50%?  

1) Doesn't work, 2) Destroys the gameplay balance of the room.

On 30. března 2017 at 2:27 AM, Jaws In Space said:

Okay so here's a screenshot showing the Nodes viewer mode. From what I gather from your link, there are too many sub sectors in this map & that's what's causing the Visplane overflows?

High seg/subsector count doesn't mean high visplane count, because the renderer automatically merges neighboring visplanes with same floor/ceiling height and sector brightness properties into one visplane, which tends to decrease the count a lot and the resulting visplane(s) actually matching the shape of a whole plane rather than the shapes of subsectors or even sectors.

Sometimes visplanes are nothing more than the number of two sided lines in view at one time. You can hide some of them behind a wall so they don't all show in view at one time at that may take care of it.  in the eternal doom level called the "great hall" I believe,  They had to hide some of the lines from the checker board floor behind a wall to kill the visplanes error when looking into that room from out side.  That is why you have to dodge around a smallish wall just inside the doorway when going into the great hall area.  I am sure glad they kept that area in there.  it is gorgeous.  The vanilla limit as I recall is 175ish lines, if that is right, so  For vanilla I try to not see/view more than 20 ish sectors at one time. 

these are not exact numbers but may work as somewhat of a guide.  Somewhere around I remember seeing the exact numbers in the doom bible or perhaps it was the lines types text.  don't know if any of those sources still exist.  google archive maybe???  not sure...

Doing this from memory, which may have faded over the years.

Edit:

May be still available somewhere.

Ok Found the visplanes overflow source:

"The Truth about Visplane Overflows"

09/20/1997

By Lee Killough

The number of visplanes is unrelated to the number of lines in view, that would be the number of drawsegs. The number of sectors is also unrelated, as sometimes 2 sectors cause over 128 visplanes and other times over 128 sectors cause no more than 2 visplanes. See here: https://doomwiki.org/wiki/Static_limits

I think your easiest solution might be to aim for limit removing, rather than for vanilla.