How to make windows with breakable glass
by Egir Helgrimson

      This tutorial is going to explain every single little step from having a wall to having a wall with a window, that looks good. I asume you know how to make a brush.

      Here we have the wall. Now we want to make a gap through it 64x64. Make the gab with the clipping tool. Make it 64x64 32 units above the ground. Now it hopefully looks like this.

      Now add a frame. The wall is 16 units wide. The frame should be 4 units wide and as broad as the wall.

      Find a glasstexture and create a glass brush inside the frame. I use the GLASSBLUE1 from halflife.wad. The brush should be placed in the middle and have the width of 2 units. Looking like this.

      We need more brushwork B). Add a windowsill. length=64, height=16, width=16 and edge=8. See the picture below for a better description.

      Mark the glass brush and make it into an entity by pressing CTRL + T. Choose func_breakable in the dropdownbox as shown below.

      Set the rendermode to Additive as shown on the image below.

      Set the FX Amount to about 80. Like this.

      Close the object proberties. Now everything should work. Lets see how it looks and works like from within the game.

      It looks somehow like a window. yay for that.

     And we can break the glass, hurray.

     We can even jump through it. Now go fill your map with windows B)