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TeamSpen210 edited this page Jun 20, 2025 · 12 revisions

Manual Installation

This installation guide will cover how to install Hammer Addons.

Note

Hammer Addons comes pre-installed with (all?) games using the Strata Source branch of source. Installation instructions for these games will not be provided.

Download HammerAddons

Download the latest release from the releases tab. Extract the contents to somewhere convenient, for example to a HammerAddons folder inside your steam library directory. It doesn't matter where, just note down the file path. This way multiple games can reuse the same install.

Install postcompiler

Step 1

In hammer, open the expert compiler menu and add a new step to the compile configuration.

Tip

To open the expert compiler menu, you'll need to load a map first. Once you've loaded a map, open the expert compiler menu by pressing File > Run Map or F9 then pressing Expert.... If you don't see this appear, you're likely already in the exxpert compiler menu.

Image showcasing where the "new" button is located in the compile dialog. Many people seem to not be able to find it, so this illustration should hopefully make it clear

Step 2

Move the new step underneath the vbsp step.

Tip

Postcompiler means it runs after (post) the bsp step.

The viewer can hereby see which button is used to move the step around

Step 3

Select the empty step and set the command to Executable.

This image illustrates where one can select the setting "executable"

Step 4

Navigate to postcompiler.exe inside the extracted folder.

Yes it's dark theme

Step 5

Set the command parameters to --propcombine $path/$file. Make sure the step is ticked on. That's it!

Shows how to copy paste stuff from the readme

Tip

If you want to copy the postcompiler exe elsewhere, note that it requires the binaries and transforms folders to be present alongside it to function.

Install custom fgd

To install the custom FGDs for a game, copy and paste the relevant .fgd file from the extracted folder into the game's bin folder. Provided is a list of each supported game and the .fgd which the game uses:

Game Name .fgd Name
Alien Swarm asw.fgd
Black Mesa blackmesa.fgd
Counter Strike: Global Offensive csgo.fgd
Half-Life 2: Episode 2 ep2.fgd
Half-Life 2: Episode 1 episodic.fgd
Garry's Mod gmod.fgd
Half-Life 2 hl2.fgd
INFRA infra.fgd
Left 4 Dead left4dead.fgd
Left 4 Dead 2 left4dead2.fgd
Portal portal.fgd
Portal 2 portal2.fgd
Team Fortress tf.fgd

That's all there is to it!

Important

The custom FGDs load custom models in hammer for preview of certain entities (Like prop_portal). To install, see Install hammer models.

Install hammer models

Step 1

Take note of the path to the hammer folder inside the extracted Hammer Addons folder. The easiest way is to navigate inside the folder, then click on empty space in the address bar to allow copying it to the clipboard.

Step 2

Open the gameinfo.txt file for the game you're trying to install Hammer Addons into and add Game "path/to/hammer/folder" as the last line in the SearchPaths.

Here is an example with Portal 2:

"GameInfo"
{
	game 		"PORTAL 2"
	title 		"PORTAL 2"
	GameData	"portal2.fgd"
	gamelogo 	1

	SupportsDX8     0
	SupportsXbox360 1

	FileSystem
	{
		SteamAppId				620	
		ToolsAppId				211

		SearchPaths
		{
			Game |gameinfo_path|.
			Game portal2_dlc2
			Game portal2_dlc1
			Game platform
			Game "C:/Program Files/Steam/SteamLibrary/hammer_addons_v2.5.3_win64/hammer"  # <----
		}
	}
}

Caution

Garry's Mod users need to be aware that the game doesn't use gameinfo.txt anymore. Instead, cfg/mount.cfg should be used.
Reported by #292.

That should be it!

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