DoLightSpreadExp(3D)

NAME
DoLightSpreadExp - Create a light attribute object defining light intensity falloff with angle

SYNOPSIS
C:
DtObject DoLightSpreadExp(exponent)
DtReal exponent;

FORTRAN:
INTEGER*4 DOLTSE(EXPN)
REAL*8 EXPN

DESCRIPTION

DoLightSpreadExp creates a light studio attribute object that defines a multiplicative factor modifying the light intensity of spot lights as a function of the angle from the light direction. For any point p, a line can be drawn from p to the light position. The cosine of the angle between this line and the light direction vector raised to the power exponent is used as a multiplicative factor modifying the light intensity at the point p.

ERRORS
DoLightSpreadExp will fail if exponent is less than zero.

[WARNING - value out of range]

DEFAULTS
The default value for DoLightSpreadExp is 0.

SEE ALSO
DoLightSpreadAngles(3D), DoLightAttenuation(3D), DoLightType(3D)