Portal Tut comin at you by maskedavenger!

This tutorial will cover advanced portalling. This includes outdoors, t-junctions, and the like. Enjoy!



Here's the layout of what I'll be splitting into cells. Cells are mapper designated sections for the game to split into areas where if you can't see that area, it doesn't get drawn. I'll be splitting this into 4 main cells. I'll be adding a little tower later to show you how to blend outdoor and indoor cells, as well as go over detail and structural brushes.



First you want to put a caulk brush under your terrain. I have walls around my terrain to act as the outside cell walls. If your terrain goes off into the distance, you'll want to make a portal instead. Make the caulk base close off the walls so that it's a big open topped box. The reason this needs to be done is terrain is automatically detail in Call of Duty, so it can't be a wall to a cell, therefore we have to make the bottom.



I do outside portals my own way. It works very well though so I'm willing to teach it because it makes things so easy. Basically I make cells by moving from one cell to the next. I've made 3 portals here, the top and left and bottom side, to complete the cell. You'll want to bevel the edges so nothing overlaps. You'll be doing this to all the portals so get comfortable. These portal walls make the first of 4 main cells I'll have. You'll want to make all the sides common/portalnodraw for now until the next step!



Now select the outside faces of portals (ctrl-shift+click) and make them common/portal. This is the way I interpret this: Portals are two dimensional. Therefore, the 3rd dimension of the brush has to be ignored. By making one side portal and the others portal nodraw, the game only really recognizes the blue plane. This is important because what face you make portal is the most important part of portalling, especially when you throw in t-junctions (coming up). My method of making boxes and covering the outside always in blue has always created correct portals for me if I do it correctly. There's one mistake, but I fix it :)



Now I've added the next box. As you can see to create the new box I only needed to add 2 sides. This 2d picture shows what i mean by bevel the edges. 45 degree angles so they line up perfectly.



And make the outsides blue! A note here before I go further: once you make a cell, don't touch it. Don't bevel it or anything. Just butt brushes up to one another. Like these ceiling portal walls, they just touch at 90 degrees.



I've done the other two. Move in a clock-wise pattern. If you do this, the last portal ceiling won't need any beveling. in this case, the one on the top left. I haven't put this in yet for a good reason.



I added a tower! I wanted to put this in to show how to merge this stuff. Let's check it out.



I made a nice front to it to show something that might seem difficult to do but isn't. I've put this together so that it will make for easy portalling. If you follow these guidelines it'll be very easy for you. If you've seen Wyatt's videos, you know that we need to portal that doorway. But it has a rounded top! No worry! That is a thickened patch by the way. I've cut out those pillars so that anything jutting out from the tall wall is a different brush. Highlighting everything I want there and hitting Ctrl-Shift-D will make those detail. Here's the explanation of detail and structural brushes: VIS for Dummies
That guy does a great job. Thanks blank for the link!

Now that you know why we need detail brushes, let's hit ctrl-d to see what I made detail. This picture shows no detail brushes. As you can see I split some brushes up so that I could make a perfect rectangle opening with structural brushes. As you learned from the above link, detail brushes don't matter when drawing portals, so we'll leave them off right now since that's what we're doing. Getting into the habit of portalling with detail brushes off is very beneficial. The neat thing is, is every time you come across a brush that you want detail, highlight it and hit ctrl-shift-d and poof! it's gone! now you can work without it there and know exactly what you need to do.
Now I've portalled it, making all sides portalnodraw except one.



In here you can see what needs to be done with the architecture.. Notice the walls go all the way down to the base of caulk. This is a must. See under the doorway portal is a caulk brush going down (highlighted).



Now I added a portal ceiling in there to close off that cell. They're highlighted. Let's get to portalling around this tower of doom.



Oooh! a pinwheel! This is how I portal buildings. Call it the swastika method of you like, but I don't want to. You can see how I did this. Each side has only one portal coming off it and they meet the next wall.



This is where portalling gets to be fun. So I made these next pictures bigger to help you see. Here there are two brushes making up the portal ceiling. This is because one needs to be beveled to meet up with the portal wall on the top left. Both new portal walls are bevelled to meet the ceiling. Take this cell you've just made and make the outside common/portal. This is also our first instance of a t-junction. YAY!!!! Here's another part to my method. First off, t-junctions are whre 2 portal walls intersect. See, they have to do it in a nice manner. One portal wall can't be running along 2 cells. Therefore, we need to cut them at the perfendictular intersection. In my method, determining this is simple. It's going to be outside the blue, so cut it like it's shown there, meeting the 2 blues.



I've gone ahead and done the next 2 cells. The one on the top left doesn't intersect another portal wall, but this one does. Here's another example of where to cut the wall it interesects.



And the last ceiling is in place. Tada! I've closed off everything. Now it's time for the trickiest t-junction to be explained, and should have been earlier, except you didn't know about simple t-junctions and this one sucks!



The dreaded 4-way portal! When you go clockwise around, if you butt these up evenly, portal will be on opposite sides for each one, creating an error. Therefore, you need to stagger them. For some reason this works great and is easy when you remember to do it. Then you don't have to go back and alter any portals. The blue line represents the portal wall. The bottom side of the right wall is portal as with the top of the left, creating that portal. This also helps because as you portal the outsides of new portals, this doesn't affect it at all.


Ok, I don't have a shot of it but you'll see it in the mapfile. I've roughly cut the terrain to the poral walls. VERY roughly. You need to do this because the game goes by brushes/meshes, not by exactly pixels of what's in and out.

Let's hop in game. Type /devmap mapname to open it in developer mode. Open up console and type in r_showtris 1 and r_showportals 1 This will, as you can guess, show our tris and portals.



You can see the arch and pillars here...



...Until you move over and block it out.



And right here you see terrain behind the tower....



Until you get close enough that it will recognize it doesn't need to draw it!

You can get the .map for this tutorial here