Unity 5 Lighting Cookbook

Quick notes on how to deal with Unity 5 lighting.

Standard realtime lighting

Standard realtime lighting includes ambient light, environment reflection and realtime lights and shadows. It doesn’t require any GI or precomputed stuff whatsoever. Both options Precomputed Realtime GI and Baked GI are disabled in Lighting > Scene.

1) Ambient. Lighting > Scene > Ambient Source (Skybox, Gradient, Color) and Intensity.

2) Reflection. Lighting > Scene > Reflection Source (Skybox, Cubemap) and Intensity. Environment reflection. Reflected path that changes with the angle of the camera. Applied independently of Ambient. Looks to cause the Fresnel effect as well.

3) Lights. All standard realtime lights in the scene apply direct lighting and shadows on the objects.

Precomputed realtime lighting

Precomputed realtime lighting adds light bounces, color bleeding, and emissive materials in real time. Everything can change (light color and intensity, material color, material emission, etc) an the lighting gets updated in the scene accordingly in real time.

Lighting > Scene > Precomputed Realtime GI enabled, Baked GI disabled.

4) Light bounces. Light > Bounce intensity. Each light is configured to bounce off of objects and affect others.

5) Emissive materials. Material > Emission (texture, color and intensity). Object must be still flagged as Static.

Precomputed realtime lighting is calculated on the scene objects flagged as Static. A precompute phase is triggered whenever the Transform of any object marked as Static is modified, or when the Static flag itself changes.

The parameter Lighting > Scene > Precomputed Realtime GI > Realtime Resolution directly affects the time it will take to precompute the data. It’s ok to use values as low as 0.01 – 0.5 for allow quickly prototyping while working in the Editor.

Light bouncing and material emission affect static objects only. Light probes must be used for the precomputed effects to be applied on dynamic objects as well.

Baked lightmaps

Al lighting details except environment reflection (Reflection) are baked into lightmap textures. Only Reflection can change in realtime.

Lighting > Scene > Baked GI enabled, Precomputed Realtime GI disabled.

Lights should be configured as Baked or Mixed for allowing to seamlessly switching among Bake only and Realtime only GI modes.

The parameter Lighting > Scene > Baked GI > Baked Resolution directly affects the time it will take the lightmap to be generated. It’s ok to use values as low as 1-4 for quickly prototyping while working in the Editor.

Modifying any parameter involved in lighting (Ambient, Lights, Bounces, Emissive materias) or modifying any Static object will trigger a new lightmap calculation phase.

General GI settings

Next settings affect the Indirect Light in both realtime and baked modes: Ambient, Light Bounces and Emissive materials but not Reflection. The Scene Window > Irradiance view mode shows the indirect light.

Indirect intensity: Scales the indirect lighting.

Bounce Boost: How strong the light bounces from one surface to the next. The bounced light is multiplied by the albedo of the surface intensified by this setting.

Next settings affect the Baked GI mode only:

Directional mode: whether to store directional and specular information in the lightmaps baked in Baked GI mode.

Atlas size: size of the lightmaps baked in Baked GI mode.