SpotLight(Vector3, Vector3, Single) Constructor

public SpotLight(
	Vector3 position,
	Vector3 direction,
	float range = 3,402823E+38f
)

Parameters

position  Vector3

Vector3 that specifies the positions of this light

direction  Vector3

Vector3 that specifies the direction of this light

range  Single  (Optional)

range of this point light - range does not affect the light brightness but just disables light calculation for all pixels that are farther away

Reference