This is meant as a beginner?s introduction to lighting in the HL2 engine. If you have never used hammer before, and want the basics laid out for you, read on. First I will cover the basic entities and their settings, followed by a quick rundown on some of the cool effects you can create with a smattering of other entities. I am assuming that you already know how to create entities, edit their properties, and know the difference between point entities and brush entities.

The three basic lighting entities are the light, light_environment and light_spot. The three of these combined will do almost everything you will ever need. They are all point entities, and so are visible in the ?entity list? when the ?entity tool? is selected. Note that the light_dynamic entity is not covered in this tutorial.



The light entity is the simplest of the three. It defines a point in space from which light shines in all directions. Its settings are fairly self-explanatory. The most useful options to be had in the properties dialogue for this entity are ?brightness?, ?name?, and ?appearance?. The brightness field allows you to specify both the intensity and color of the light. The name field (duh) gives it a name so that it can be turned on and off by other entities. The appearance field allows you to choose a custom dynamic. As far as I am aware, all of the available options simply vary the intensity of the light with time. In general this setting is not very useful as the flickers you can create with it can be quite annoying.




The ?light_spot? entity defines a point from which a directed beam of light emanates. This entity is great for creating dramatic pools of light underneath lamps. It has all the same settings as the simple ?light? entity, plus a few more which are, again, self-explanatory. Worthy of particular note is the ?entity to point at? field. This allows you to specify a target for the light_spot. In this way you can easily direct its beam at odd angles which might be otherwise difficult to achieve. Simply place an ?info_target? where you want the light to shine, name it, and add that name to the ?point at? field. You should also consider setting the falloff to ?linear? rather than ?quadratic? this creates a much brighter more dramatic light because the intensity of the light falls off much more slowly with distance. As you can see, a cone emanates from the light_spot in Hammer. This gives you a good idea of where the cone of light will be projected in?game.




The light_environment entity is used to light outdoor areas. Only one needs to be placed in the entire map. It?s properties are used to define the properties of the sunlight/moonlight in your map. The ?ambient? field provides a way to specify how much scattered ?skylight? there is.




Now, you?ll notice in the screen above that these lights don?t look very good in game. There is no source, no bright beam of light that you can see shimmering in the air, and no lazily floating dust particles. All of these things are required for a good looking map. Any significant detail is beyond the scope of this tutorial, but here is a list of useful entities for spicing up your lighting, and a few words on their uses to get you started.

prop_static:
This is a point entity that enables you to place a model in the world. Use it to put in the light fixture of your choice.

point_spotlight:
This is a point entity that creates that cool ?light beam? effect that you may have admired in the single player game.

env_lightglow:
This is a point entity that creates a halo effect around a light and makes it look bright, and just generally cool.

func_dustmotes:
This is a brush entity that is used to create the cool floating dust particles you may have seen in de_dust.