Developing a game in Source - Part 1
25/05/2026

So, what is Source?

Source (2013 base if you want to be exact (and even more MapBase)) is a game engine developed Valve. It powers iconic titles, such as Half-Life 2, Portal and Portal 2. The SDK is open for people who want to make mods… so lets get into that.

Making a mod: my plan

My plan is a game that runs on top of the Source 2013 Singleplayer Base (Half-Life 2). Well, technically, you don’t need a copy of Half-Life 2 since I pack the VPK (Valve PacK) file for Half-Life 2, but in most cases, Steam will refuse to boot the mod if you don’t own it.

My game is called PATCHBAY; It is set in an old Aperture Science facility under City 17. I won’t spoil the story, but just know that is the base.

The pain of Valve’s toolset

At the core of the developer experience, you have Valve Hammer. Hammer is where the maps come together; It compiles VMF (Valve Map Format) to BSP (Binary Space Partitioning). Hammer is bundled with all source games. Be it Garry’s Mod, Portal 2 or Half Life: Source.

Hammer will be your best friend and worst enemy at times. Most of the time it will be your worst enemy.

In MapBase (what I have forked my branch from), env_fade had been marked “OBSELETE!”

This means env_fade did not exist. I am still stumped on how to implement my “wakeup” animation.

Conclusion

Source is great. Hammer is not.

See you tomorrow for the next update!

-meowcat767