Inside Macintosh: 3D Graphics Programming With QuickDraw 3D /

Chapter 8 - Light Objects / Light Objects Reference

Data Structures

Light Data Structure

You use a light data structure to get or set basic information about a light source of any kind. A light data structure is defined by the TQ3LightData data type.

typedef struct TQ3LightData {
   TQ3Boolean                 isOn;
   float                      brightness;
   TQ3ColorRGB                color;
} TQ3LightData;

Field Description

isOn

A Boolean value that indicates whether the light source is active (kQ3True) or inactive (kQ3False).

brightness

The brightness or intensity of the light source. The value in this field is a floating-point number in the range 0.0 to 1.0, inclusive. Some renderers may allow you to specify overbright lights (where the value in this field is greater than 1.0) or lights with negative brightness (where the value in this field is less than 0.0); the effects produced by out-of-range brightness values are renderer-specific.

color

The color of the light emitted by a light source.