Understanding Lighting - Adobe ATMOSPHERE User Manual

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CHAPTER 13
Even sophisticated environments seem fl at without lighting.

Understanding Lighting

Atmosphere uses advanced Radiosity lighting algorithms that produce realistic lighting effects. Radiosity takes into
account the way light behaves in the real world. There are two kinds of lighting in Atmosphere – pre-computed
lighting and dynamic lighting. Pre-computed lighting is calculated before the environment is viewed in the Player.
When you click the Start button in the Lighting Control, lighting information is calculated and saved with the scene.
Dynamic lighting is applied in real-time as the user interacts with the environment.
What is a Light Map?
A Light Map can be thought of as a global texture that overlays the scene. This map includes lighting information
such as highlights, gradients across surfaces, and shadows.
Light Maps can be enabled or disabled for each object using the Has Light Map option in the Light Map tab of the
Inspector palette. If enabled, editable Brightness and Sample Size values appear.
Where are the Lights?
The main light source in Atmosphere is the sun, which behaves like the sun in the real world. In addition, any Solid
Object or Surface Object in the scene can be a light source. The faces of objects that emit light are called emissive
surfaces. Typically, interior scenes are lit by lights that you create and position, while exterior scenes are lit mainly by
the sun and the background.