to a point light source, but emits light in a specific direction in the shape
of a cone.Source: Unity3d
spotlight radiates light within a cone.
In addition, light is modeled so that it is brightest along the
direction the spotlight is pointing.
this we required three additional light properties:
rendering a point, we first check to see if it’s inside the cone. If it is not inside the cone, we just return
the ambient term.
- a direction the
spotlight is pointing
- a cutoff
angle, used to define a cone around the direction vector
- an exponent,
describing how light falls off from the centre
the point is inside the cone, we determine the intensity of the spotlight at
the point based on the form