ERROR: portal has the same cell on both sides, portal ignored

What does that mean, 'same cell on both sides'?


When portaling and adding the 'sky portal' brush, how far does the brush have to extend over the map? Does it have to cover the entire map from one edge of the skybox to the other?

If adding two portals opposite each other, do the portal textures have to face away from each other?

Okay, so just to reinforce my theory that this editor hates me, below you see I created a simple map. I put in one wall dividing a single room in half. I placed a portal brush between the two rooms covering the doorway aaaaannnd... I STILL GET THIS FRIGGIN ERROR!!!!

ERROR: Portal has the same cell on both sides, portal ignored



So tell me, how is it that you guys are using multiple portals in your maps but I can't get ONE to friigin work?!

JerryAtricks writes...
You can't use portals like that. It looks like it just fills in the gap between the door and there is nothing sealing the portal. Think Portal "cells". They can't be left open like that.

Download this quick and dirty portal sample map file, JerryAtricks:

http://www.megaupload.com/?d=8RV4GS03

Thanks for trying to help, but it is yet again, another half explanation.

What is two portals in an empty room with no walls supposed to explain? How to portal an empty room? Great! I'll just remove everything from my map and all will be well with my portals!

The portal in the above pic is placed like EVERY tutorial I've seen tells me to place it. So is every tutorial on Modsonline incorrect? Is it supposed to extend into the wall? It does. It goes 4 units into the walls and floor. Is it supposed to divide the entire map in half? Please, fill me in here.

As for the example you sent. The sky portal is split down the middle above the two portal brushes. IS that supposed to mean that whereever there is a portal dividing the map, the sky portal is only supposed to fit to the edes of the portal brush below it?

ur getting that error cos that portal really hasn't divided anything. if u had another brush (like a roof or horizontal portal brush) over the top then it would work cos the portal texture you have there and the walls of the room would seal off any gaps and you'll effectively have two cells.

portals are meant to divided ur map into different cells so that parts of ur map don't have to be drawn by the game engine until they need to be. also, u don't need to have ur portals extending into other brushes. just have the edges match up and fit nicely with everything else. make the grid size smaller if u have to.

edited on Nov. 8, 2008 02:59 am by ilikepotatoes

edited on Nov. 8, 2008 03:06 am by ilikepotatoes

Texture the other side of the portal with Portal No Draw.
That usually helps (if it is close on the other sides like the other comments mention).

JerryAtricks writes...
I don't offer half explanations. I try to help based on how people describe their problem. Your screen shot looks like a portal brush spanning the distance between two walls. Short of actually having your map file so that I can see everything you're not representing in the screen shot, my advice is that you do not use portals that way. That's a FULL explanation.

Someone might offer to take a look at your map and help you out if you're gracious about it. From that you can study portaling and learn about all the different ways to do it the right way. You can also open up the backlot_geo.map and study that as well.

P.C. Invasion: Sorry dude, I'm not trying to be offensive, I'm just really frustrated with all the half answers I'm getting, and yes, while you may think you didn't give me a half answer, you did. You said; "You can't use portal like that..." but then never offerd the reason why or how to do it. See what I'm saying? Those are the typical replies I get, so I'm not directing my frustration towards anyone in particular, especially not you. And you can see in my other posts I'm pretty much mellow. It's just these friggin portals are driving me insane!

What you see in the pic is pretty much it. A room with a wall dividing the room in two and the portal brush between them. Other than taking an overhead shot there's not much more to figure out.

The file you sent told me absolutely nothing about how portals are supposed to work, so therefore proved useless to me. The effort to help was much appreciated, however.

Someone has since sent me a full explanation on how portals work and how to place them and it has worked flawlessly, so we can consider this thread ended. But again, thanks for your help, it was appreciated.

I think i know what that means. make sure the portal is covering everything, if you have 2, make sure there not over lapping. But the error your getting i think to fix it is this.

Get your portal texture, select it the press shift + control on the inside portal then texture it portal no draw. so bascily, the top bottom left, right and where you walk in should be "portal no draw" texture and the 1 were you walk out should be portal. thats it if that don't work i don't know what will.


thanks ukdjaj