Hammer 3.4

Creating a dark environment - by Andy

Not all of the maps in the original HL were daylight bright, but most of the outdoor maps were. Counter-Strike has enabled the player to use "Nightvision goggles" for the first time, and there is no point in running around with them on, in full daylight.
Here we will try to cover the easiest method of adding darkness to your level.

With your outdoor area open in Hammer go to the tool bar and select Map and then Map properties... you should be presented with the Worldspawn Object Properties box below:

Change the environment map (cl_skyname) to a suitable night type sky.
The darker defaults in HL are:

• night
• space
• black
• dusk

You could use a day time sky texture, but it will look really odd, because the texture is not actually lit by the light_environment. It will be bright and visible regardless of the settings you change. Changing the Default Light Level in the Worldspawn Properties does not seem to do anything regardless of the figure entered.

Light_environment:
Add a light_environment (or a light_spot with FLAG: "Is Sky" checked) to your map. If you compile your map now, you will get something that looks like this:

This is because the light environment has a default brightness of 200.
Open the properties for the light_environment and adjust the 4th number in the sequence to a lower figure. The example map is set to 2.

NOTE:   If you change it to 0 it won't go black, it will actually appear like a medium lit map. The other three numbers in the sequence are Red, Green, Blue identifiers. Using the Pick Color option will change these figures, but will not change the 4th number.

You can change the Pick Color option to add atmosphere but you will notice that the actual brightness of the map is not effected by the Luminosity of the colour chosen. Changing the colour to a deep blue or red will give the map some more feel, if it is a bit lighter than the example map.

Great, Now we have a dark outdoor map just waiting for some action. I added a small texture light just to give the map some perspective, and some thing to look at..

If you have the SKY texture in other areas of your map, they will appear the same as this area. You only need one light_environment in a single map regardless of where the sky textures are, however if you are using Zoners Half Life Tools 253 custom Build 1.7 then you can make use of the -noskyfix line for your RAD compile to make use of multiple light_environments.

There is a lot more you can do with the light_environment and skies, but this is just a really basic starter tutorial, If you are using ZHLT 253 1.7 then you have the option of adding -ambient to your hlrad compile. Figures like:
-ambient 0.0040 0.0040 0.0040
Will add a small amount of ambient light to your shadows. The figures are very sensitive but the ones above seem to work best for general level design.