Lighting

Guides

• Adding Light - A beginners tutorial on how to set up a basic light entity.
• Intermediate Lighting - A tutorial dealing with all the light sources in more detail.
• Advanced Lighting
• Constant-Linear-Quadratic Falloff - An easy-to-read explanation of the old C-L-Q light attenuation system.

Entities

Stationary light sources

• light — a simple omni-directional light
• light_environment — light from toolsskybox materials
• light_spot — a stationary spotlight

Moving light sources

• light_dynamic — a combination point light and spotlight that can be moved, turned, and adjusted.
• npc_spotlight — a spotlight NPC capable of tracking targets.

Other light effect entities

The following entities are primarily just visual effects from light, meaning they do not cast light on their surroundings.

• env_sprite — entity used to create omni-directional glow or flare effects.
• point_spotlight — a moveable spotlight (directional) glow, with an optional dynamic light source.
• env_lightglow — an asymmetrical glow (for areas of contrasting light).
• The models/effects/vol_light001 and models/effects/vol_light002 textures, used for volumetric lighting.
• prop_static — This entity can be used together with the models/Effects/vol_light.mdl model to simulate basic volumetric light.
• env_sun — visual effect of the sun in the sky.
• env_particlelight — only lights particles (such as those produced by env_smokestack).

Common values

City 17 day

Brightness 237 218 143 800

Ambience 190 201 220 100

Ravenholm night

Brightness 175 230 239 50

Ambience 43 45 57 5

Combine lamp

Brightness 147 226 240 3000

Ambience N/A

Tungsten bulb

Brightness 254 216 146

Ambience N/A

Fluorescent bulb

Brightness 159 237 215

Ambience N/A

For values to accompany the stock skybox materials, see Sky List.

Notes

• Naming a light makes it more expensive. Only name lights when you need to. Multiple lights sharing the same name are cheaper than lights with separate names.
• light_dynamic is especially expensive, and will not even show up on some systems
• The basic light entities do not come with a visible representation (e.g. a lightbulb). For that you need a prop. See HL2 light props for a list.
• The basic light entities do not come with a "glow" as you'd expect to see in a foggy or misty area. To provide this, either compile and run the map with HDR enabled, or add a point_spotlight (with dynamic lighting off unless needed) or env_lightglow entity.
• Maps will not be lit unless you run vrad (or equivalent). Vrad will not run properly and will not calculate realistic light bounces unless the level is free of leaks.
• Several textures provide their own light & can do so using lights.rad in a mod's directory or the one in sourcesdk/bin.
• Moving brushed-based objects will not change the way they are lit. Their lighting will be calculated only according to their positions in Hammer. (e.g. a brush in a dark room will not become bright if it is brought into a bright room.)

Console commands

• mat_fullbright boolean — Toggles map lighting

See also

• HL2 light props
• Color theory (level design)
• Light entities - A list of light entities.

External links

• Understanding and Using Lightmaps - Tutorial
• Volumetric Lighting - Tutorial
• Lighting Tutorial - Covers entities & variables with examples
• Quadratic/Linear/Constant in Lights