Pick up the crowbar of research scientist Gordon Freeman, who finds himself on an alien-infested Earth being picked to the bone, its resources depleted, its populace dwindling. Freeman is thrust into the unenviable role of rescuing the world from the wrong he unleashed back at Black Mesa. And a lot of people, people he cares about, are counting on him.

This is a tutorial explaining the basic way of creating 3D Skyboxes in Hammer.

Posted by Sythen on Jul 20th, 2008
Intermediate Mapping/Technical.


Hey guys! and welcome to my first tutorial! In this tutorial you will be tought how to create 3D Skyboxes in Half-Life 2's level editing utility. Hammer! Also, I will not go into how to make a room, simply tell you what I did and what textures I used. Then show a screenshot for you to follow along, as it is easier.

Step 1:

I have already created a room that I will be using, it's a really REALLY basic outdoor map, and is only used to show an example. So the first thing you will need is a box room. Next, make sure that the walls and ceiling of the room have the "tools/toolsskybox" texture. This room is 512x512x512, and just has some basic walls going around the parameter.

Step 2:

Alright! We have a room! :D Now we need to work on another room, to make this easy, you can select all the brushes and shift drag it to a different location. Now that we have two rooms, we need to delete the walls in our second room, and make sure that all the walls have a "tools/toolsskybox" texture.
On the left is the perspective view of the second room, on the right is the top view of both rooms.

Step 3:

Right! This is were it get's a little tricky. First, you need to have a light_environment entity pointing in the exact same direction, in both rooms. This helps with keeping the lighting correct. In the center of the second room you will need a sky_camera entity, place this low to the ground but in the center of the room. And then finally, you just need to lob some skybox models AROUND the sky_camera.

Finished Product:

Hopefully, all the walls that you placed the "tools/toolsskybox" on in the first room, will be replaced by huge towers. :) Giving you your 3D Skybox :D

Example Map: www.scottbaker.eu/tut_3dskybox.rar


Post comment Comments
Silverfisk Jul 21 2008 says:

Doesn't the sky_camera give its output from the center of the map (The center of the map = the place the sky_camera is, sort of)? And maybe you should mention that everything is 1/16th of it's original size in a 3D skybox?

I guess it's an ok tutorial but it's too shallow in my eyes.

+4 votes     reply to comment
Wills Jul 21 2008 says:

Aye, firstly sky_camera needs to be placed at the origin of the map, and copy/pasted with the rest of the reference geometry so that both sky_camera's have matching positions relative to the map.

Secondly, the skybox needs to be 1/16th the size of the original room, which can be done by going to Tools; Transform, selecting scale and typing .0625 in the X, Y and Z boxes. You then can place geometry, displacements and skybox ready models into the skybox, all at 1/16th the original size.

These are then resized up to the correct size by the engine when you play the map. If you use displacements in the map though (like de_dust), then make sure you scale the textures down to around 0.05, otherwise they will look huge and ugly.

Nicely laid out and written tutorial, but you've really missed the whole idea of 3D skyboxes, and what makes them awesome.

+4 votes     reply to comment
CrowbarSka Jul 21 2008 says:

Yeah and you also need to delete the sky_camera from the main (full-size map). This tutorial is totally incomplete and does not show someone everything required to make a 3D skybox.

Also it could be explained much better. "Shift drag" and "skybox models" does not really give a clear indication of what that is.

+2 votes     reply to comment
benguy1 Jul 30 2008 replied:

@crowbarska he never placed a sky_camera in the main full sized map read the tut before u comment n00bc4k3

+2 votes     reply to comment
Sythen Author
Sythen Jul 21 2008 says:

Yeah sorry about that guys, I really should have gone more in depth with it, I will continue to add more to this tutorial. And then state when I have finished it.

Apologies for not mentioning the main parts that are actually needed. But as this is really basic, I wanted to show the steps I took for a friend who was having problems with his.

Sorry again, I'll keep you posted.

+4 votes   reply to comment
Wills Jul 21 2008 says:

Good to hear it buddy! I'll look forward to the updated version :D No need for apologies, just trying to help and make sure it's all factual!

+2 votes     reply to comment
Vizitas Jul 22 2008 says:

3 out of 5

+1 vote     reply to comment
somegamer Jan 19 2009 says:

Hey, just a quick question to all, is it possible to get a npc model for example breen to, when put in a sky box which is going to look as far bigger as possible than what it realy is, have its size increased with the sky box, or, more simply put, can i make breen look like a giant by putting him in a 3d skybox and looking at him in a map. Please email me or tell me via steam. Email is nathan.davies-lee1@education.nsw.gov.au Steam friends name is '~{MM}~Somegamer' without the ' marks on the sides. It says im in new zealand but it is lie. Da owner (my brother) lives in new zealand.

+1 vote     reply to comment
xenbiosis Aug 4 2009 says:

Hell yeah! Thanks a bunch for the guide.

+1 vote     reply to comment
half-life Oct 24 2009 says:

already knew how to do this, but great guide easy to understand for average hammer users, oh, and nice example map.

+1 vote     reply to comment
Hezus Jan 25 2010 says:

Here's a good video tutorial:

+1 vote     reply to comment
Delfador Jun 5 2011 says:

Hey guys, I need help. I experimented a lot with this 3d skybox, looked at the sdk_3d_skybox.vmf file that comes with the Source SDK, but the buildings that I place in the smaller room do not appear at all! I followed this and other tutorials and no luck. Any suggestions?

+1 vote     reply to comment
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