NAME

DoLight − Create a light studio object

SYNOPSIS

C:

DtObject DoLight()

FORTRAN:

INTEGER∗4 DOLT()

DESCRIPTION

DoLight creates a light object.  A light is a studio object.  It obtains properties only through attribute inheritance and then only during execution of definition objects.  Lights obtain their position and orientation through inheritance of the current transformation matrix attribute. 

All lights have intensity and color and are of a specific type.  The intensity and color are determined by DoLightIntens <DOLI> and DoLightColor <DOLC>.  The light type is determined by DoLightType <DOLNT>.  Depending on the type, some lights also have one or more of the following: position, direction, attenuation, spread angles, and spread exponent. 

Light objects are not visible; only their effects are.  One may have an arbitrary number of lights per view.  Lights can be turned on and off per primitive object in the scene (see DoLightSwitch). 

DEFAULTS

The default light model is an infinite light source of intensity 1.0 located at the origin and pointing down the Z-axis in the negative direction. 

SEE ALSO

DoLightColor(3D), DoLightIntens(3D), DoLightSwitch(3D), DoLightType(3D)

September 02, 1992