Game Development Reference
3. Spotlights have all of the same important properies as point lights (color,
brightness, radius, and fallof), but they have a few addiional properies as well.
Make sure your spotlight is selected and opens up its properies. Look for two new
OuterConeAngle : How wide of an angle the cone covers.
InnerConeAngle : Controls the hotspot in the middle of the cone. If it's 0 , it'll
cast a very soft circle of light. If this is the same radius as the OuterConeAngle,
the spotlight will cast a hard-edged circle of light, but you may lose detail when
you bake lighing.