Half-Life 2 Game Creating basic destroyed walls tutorial

One of the most common design elements in Half-Life 2 maps is destruction. I've noticed that many level designers do not succeed in creating believable destroyed environments. It is actually quite simple to create broken walls and collapsed ceilings. All it takes is a bit of time. With this guide, you will learn to blast holes the simple brick wall and other types of walls as well as learning how to add more feeling to the destruction.

One of the biggest mistakes made is not the actually brushwork. You need to know which texture you are going to use for the wall first. If you have a brick wall, it is imperative that the "bricks" that you will create with brushes match the texture. Bricks and blocks almost never break in half. They break apart at the weakest point, where they meet each other.

To make the actual wall segment, you need to cut out a rectangle where the break will be. Now select this rectangle and start cutting it up. Use the clipping tool to cut horizontal slices in the wall. Use the camera view to make sure these slices are on the meeting places of the bricks. Now simply cut up the layers vertically using the clipping tool. Be sure to give the lengths of these segments some variety. Here you can see a broken wall aligned with the texture. You should tie the debris to a func_detail to maximize performance.

Not all walls are made of bricks though. For your generic concrete wall, displacements are the way to go. This time you will need to cut up your rectangle into equally sized squares first. In the example picture below, I used 48x48x16, but any size will do. You need to place them in a grid pattern, but delete the ones in the middles. This is where your hole will be. Select all of the visible faces of the squares and turn them into displacements. Mine are at a power of 2. The power you use depends on the block size. Before you start manipulating, you must sew them together! This is very important- you don't want leaks between your displacements. Now just use the paint geometry tool to add some noise to the blocks. And voila!

For metal walls, use a technique similar to the brick wall method, but with bigger chunks. The vertex tool should be used to add depth, to make it look like the metal exploded and bent outward or inward.

You aren't done with just a wall. Add props to make it look like something really exploded, hurling debris everywhere. Pipes and rebar in the wall can add to the effect as well. For broken pipes, you can use env_steam for a nice touch.

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