The Source SDK :: Guest Blog

Guest Blogger: Forte

A great way for beginners to get into level design is through the Source SDK's built in level editor: Hammer.

What is the Source SDK?

The Source SDK is an easy to use software development kit produced by Valve for use in games that run on the Source engine, such as Portal 2, Team Fortress 2, and Half-Life 2. Of particular interest to the beginner level designer is the Hammer World Editor. The best part is that it is free to anyone who has installed Steam (Valve's digital distribution platform), and can be downloaded from the "Tools" tab in your Library.

Intro to Hammer

Hammer is a relatively simple world editor that allows its users to quickly develop simple levels. Of course, to make a working level for a game, there are hundreds of factors to consider, depending on the kind of game you want to design for. The basic interface shows you four windows within the Hammer window: 3D View, 2D View (Top Down), 2D View (Left Side) and 2D View (Right Side).

The Windows

The four windows are your workspace, like a blank canvas in Photoshop. The 3D View window is a visualizer into your new level, allowing you to see sort of a rough draft of your level without having to compile it and run it in a game. The 2D Views allow you to drag out brushes along the X, Y, and Z axes.

Brushes

The term brushes refers to what can essentially be described as platforms. These are (usually) the physical objects that make up your level, but can also be scripted sequences to activate things within your level, depending on the texture you assign to them. To draw a brush out, you first click on the brush icon: , and then simply drag out an area in one of your 2D windows. Don't worry if you don't get your brush exactly right when creating it, you can always resize it by clicking and dragging on one of the white squares that appear on the outline of the shape while selected. The best part about Hammer is that every brush always remains self contained, so you can edit it as much as you would like after its creation, including changing the texture on it.

Textures

Textures are of course the "skin" given to your brush. The texture window is on the right hand side of your screen by default, and looks like this: . To select a texture, you simply click the browse button, which will bring up a dialogue containing all of Hammer's built in textures. You can type into the name bar at the bottom of the textures dialogue to help make your search more specific, or you can just look through all of the textures to pick one you like. When you create a brush, the brush will have the currently selected texture on it, but your texture can be easily changed by clicking on the brush, finding a new texture, and then clicking the reskin button:

Entities

Entities are pre-scripted objects that you can put into your map, the most important of these being the "light" entity and "info_player_start" entities. To create an entity, click on the entity button: , and then click on the position where you want the entity placed in the 3D view window. The listed entities are the most important because one, info_player_start, tells the game where to spawn the player, and without it, the player cannot be spawned. The other, light, simply creates a light to make your area visible.

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With four walls, a floor and a ceiling, and the entities listed here, you can make a quick and easy map which can be compiled and instantly ported into any Source game, so you can see the fruits of your labor almost instantly.