1. Introduction
2. A Quick Tour of Hammer
3. Constructing the Basic Room
4. Placing a Simple Light Entity
5. Placing a Spawn Point
6. Compiling Your First Map
7. Loading Your Map in the Game

After the tedious technical process of configuring Hammer and setting up your editor, this is the moment you have been waiting for. We're going to make your first map. It will not be considered a masterpiece, but it will be your very significant personal milestone.

The first thing you need to do is select the brush constructing tool, also known as the Block Tool. A brush is the term mappers use for a block of solid geometry. It could be a wall, a ceiling, part of a window, or even glass. For now, you can just think of a brush as something solid that the player cannot walk through in the map. The Block Tool is on the left side of the screen, as shown below:

Block Tool

With the Block Tool, drag a square-shaped block in the top (x/y) view. Drag out a 256x256 block. Don't make it too big. The dimensions in Hammer is generally bigger than you expect. After you're done, it should look like the screen below:

Your first box

In the side (y/z) view, drag the rectangular shape until the block is 192 unit tall. When the block is 256 unit wide, 256 unit deep, and 192 unit tall, hit Enter to create the block.

Box created

You're not done yet. The block you just created is completely solid. It's just like the wooden block kids play with. Players and entities cannot exist inside a solid block. So now you need to hollow out the inside of the block to make it into a room.

With your box still selected (the edges of the box in 2D view should be red), press Ctrl-H. A small dialogue box pops up, asking you for the thickness of the wall. As prompted in the dialogue, a negative number will extend the thickness of the wall outward, allowing more space inside the hollowed box itself. I tend to always hollow outward, so type in -32 for the thickness, and press Enter.

Hollowed box

For future references, the external wall of a map should always be at least 8 unit thick. Anything thinner might cause a problem with leaks. I'll address leaks in another tutorial. For now, -32 units will do the trick.

No, we're not there yet. We still need at least a light entity and a spawn point in the box. These are the minimal requirements for a map to load.