Visportal testing

[Fidcal]

Most of us have likely been using r_showportals 1 to test if visportals are working but I now know this is not enough. Quite a few visportals in my FM had edge gaps yet still showed red/green correctly and blocked tris. But they still leaked sound propagation - at least alerts to AI anyway.

 

So, don't trust the red/green thing completely. Until someone comes up with a better method, we need to keep checking edges manually. In a big complex FM this needs repeating from time to time because later changes can affect edges without realizing it.

 

Filter out all entities and patches, clip and nodraw etc. before visually inspecting. Only solid worldspawn brushes seal visportals

[Serpentine]

I usually check using both showportals and showtris 2/3, sometimes you'll still get sealing but there's scissoring around the area which usually indicates that the surface isnt 100% flush. Other than that you can also change errr renderleaf? I think... it is to only show the leaf you're currently in, makes spotting gaps and such a bit easier

[Sotha]

The visportal wiki article has some recommendations for vp testing and placement.

 

Tell me, did the VPs leak sound because of non-snug fitting into the portal? Ie vp penetrating into the wall? If so, the wiki article should emphasize snug fitting vps.

 

Worldspawn penetration of VPs are a well-known source of problems.

[OrbWeaver]

I usually check using both showportals and showtris 2/3, sometimes you'll still get sealing but there's scissoring around the area which usually indicates that the surface isnt 100% flush.

 

You should always get scissoring around visportals, this is an important optimisation. Or did you mean that the scissor rectangle is larger than it should be, because the visportal extends into surrounding brushwork?

[Bikerdude]

grrr bloody VPz, will it never end..

[Fidcal]

None of my problems were caused by visportals penetrating into surrounding worldspawn AFAIK, in fact most of them do even after fixing. I always try to drag visportals into the surround so it's clear there cannot be a gap like if it were snug. Many were gaps caused by my later converting stuff to func-static. One large triangle had a tiny gap where I'd cut the corner off in an earlier attempt to get it to work. I fixed that. Now it works on one side but is black on the other!

 

I'm getting very good fps anyway considering the details and the views I'm surprised.

[Serpentine]

You should always get scissoring around visportals, this is an important optimisation. Or did you mean that the scissor rectangle is larger than it should be, because the visportal extends into surrounding brushwork?

 

The scissoring that happens when the portal is working correctly is seen exactly on the edges of the VP. A few cases where I've had funny seals that seemed to leak sound, if I looked at glancing angles to the VP there would be scissoring of the next leaf at what looked like if you had a duplicate of the VP face as a sprite facing you, it would be culling on the edges of that. I cant really explain it well. I think it's related to another form of scissoring, but havent really bothered to dig for more.

[stumpy]

the game can go iffy if you have too many visportals in the same area, like horizontally visportaling a beamed ceiling where the player can walk around on the beams, you end up with the visportal showing up as a flippy flappy black plane in game.

[OrbWeaver]

The scissoring that happens when the portal is working correctly is seen exactly on the edges of the VP. A few cases where I've had funny seals that seemed to leak sound, if I looked at glancing angles to the VP there would be scissoring of the next leaf at what looked like if you had a duplicate of the VP face as a sprite facing you, it would be culling on the edges of that.

 

At the risk of telling you what you already know -- you are aware that GL scissoring can only use a screen rectangle, right? So if you look at a funny angle towards the visportal, the screenspace rectangle used for scissoring is not going to fit perfectly with the rotated/sheared/perspective-transformed visportal surface.