How to Make a Map in Alien Swarm

Creating and Texturing Objects

• 1

  Open Steam and download "Alien Swarm" if you haven't already. Click on the "Library" menu and click on the "All Games" drop-down list.

• 2

  Select "Tools" and double click on the "Alien Swarm -- SDK" listing under "Tools" on the left-hand side of the menu. Right click the "Hammer World Editor" item on the "Alien Swarm Authoring Tools" menu that pops up and select "Launch." Now click "File" and "New."

• 3

  Place objects in the upper-right "top" view pane with the "Block Tool." It's best to place the first object at the map's origin point (where the blue lines in the top view intersect).

• 4

  Adjust the dimensions of the block by clicking and dragging the white dots that appear at its corners and edges when it is selected. Press enter to create an actual cube. This object will serve as the starting room of your custom map.

• 5

  Use the "Selection Tool" to select the cube and right click on the object in any of the 2D views. Select "Make Hollow" to turn your cube into a room with walls, a floor and a ceiling. You can either "Ungroup" the components of your cube or click the "Toggle texture application" tool and select the individual faces of an object for precise detailing.

• 6

  Delete the ceiling. "Alien Swarm" is played from a bird's-eye-view perspective; thus, the top of the cube will obstruct the player's view. Select the top of the cube after "ungrouping" the object (or while the "Toggle Texture Application" menu is active) and press the delete key on your keyboard.

• 7

  Click "Browse" next to the small square on the right-hand side of the map editor interface. This will bring up a selection of textures.

• 8

  Choose a pattern and double click it. You'll leave the texture menu and find that the small box to the right now contains the texture you've chosen. Select an object and click "Apply Current Texture" to add the surface.

Placing Entities and Structure Seals

• 9

  Select the "Entity Tool" and click a point within your hollowed room to create a player character. You may move the character within the map by left clicking and dragging (ensure that he stands on solid ground). Hold shift before dragging the character to create a clone.

• 10

  Change the nature of an entity by clicking on it with the left mouse button, right clicking on it in one of the 2D view panes, and then selecting "Properties." You can now specify the object's "Class" using the drop-down menu in the window that opens. You can create anything from objectives to monsters using this technique.

• 11

  Choose an entity and change its class to "Light." Change the color of a light by clicking on "Brightness" and "Pick Color." You may adjust the height and positioning of the light by clicking and dragging its entity in any of the view panes.

• 12

  Create a cube that is much larger than your initial room. Size and position the new box so that it completely envelops the first cube. Apply a "toolsnolight" texture to the new box.

• 13

  Click the object with the right mouse button in a 2D pane and select "Tie to Entity." Change the class to "func_brush" and assign the brush a name. Recreate these objects and have them surround the rooms of your map to prevent "leaking" errors.

• 14

  Save your map in the "\steamapps\common\alienswarm\swarm\maps\" directory when you're ready to test it. Press F9 in the editor to run the map. Click "Expert..." and press "Go!" to take a test drive.