If you happen to be making a corporate building super map, then maybe you want some funky 1 way glass in it. There's not many tuts about for this, its pretty simple as it goes, but still needs telling :P (my pc crashed when I was writing this tut! I had to write this whole bit again :)

Anyway, to begin with, I suggest you make a wall with a gap for your window to go in, like this:



Ah there we are, now we want a very tiny window to go in here, I dont mean tiny as in overall size, but in thickness, we want this window to be as thin as possible. So make a thin brush covered in glass and place it in the hole to make the window.

Like this in top view (see above), so it should then look like:

There we have it, ive made my walls a tad thick there really. Now you can see mine has the glass texture on there cant you. Well what you need to do is have one side with the glass texture like in the picture there, and the other side with the {blue texture on, you know the other side of the window! So apply the textures to there, if you know nothing about texture applying then read my tutorial if you please.

You should now have a window, one side glass texture (any one you like) and one side that {blue texture. Now select your window, and right click, and tie to entity, choose func_wall, now the usual options are there, but all you need to do is change the fx_amount to 255 and the render mode to solid.

Now we are nearing the end, you know the side of the window with the blue on? well thats going to be invisible you see, in other words, the transparent part of the 1 way window. Now you need to add some glass to it, otherwise it will just be a hole. So make another thin brush just like the other one, and place it flush on the blue side of the window, so you have 2 windows in a sandwich. Now this window you have made needs to be selected, then right click, tie to entity and choose func_wall, again leave the other options and just choose render mode addictive and fx amount to around 145-160, best try 145 :P

What next? well thats it, you have your one way window, go test it out and see who you can see, or cant see, hrmmmmmm.......