220.127.116.11 Parallel Lights
parallel keyword can be used with any type of light source.
Note: for normal point lights,
point_at must come after
Parallel lights are useful for simulating very distant light sources, such as sunlight. As the name suggests, it
makes the light rays parallel.
Technically this is done by shooting rays from the closest point on a plane to the object intersection point. The
plane is determined by a perpendicular defined by the light
location and the
Two things must be considered when choosing the light location (specifically, its distance):
Any parts of an object "above" the light plane still get illuminated according to the light direction,
but they will not cast or receive shadows.
fade_power use the light
location to determine distance
for light attenuation, so the attenuation still looks like that of a point source.
Area light also uses the light
location in its calculations.