Constructs a
Focus
using the first threereal
arguments as the x, y, and z-coordinates ofposition
, and the fourth through the sixth argument as the x, y, and z-coordinates ofdirection
. dist specifies the distance of theFocus
from the plane of projection, ang the angle of rotation, which affects which direction is considered to be “up”, and ax the major axis to which theFocus
is aligned.
Resets an existing
Focus
. Corresponds to the constructor above.