站长说的很对,补充一下: $3%EKi
Normal Vector nlK"2/W
The Normal Vector is a vector in 3D space that is used to orient the projection Zcv1%hI
plane for the irradiance map. The plane is defined to be perpendicular to the SVaC)O(
Normal Vector, and the irradiance incident on the selected surface is projected 8fJ- XFK$:
onto this plane. When the map is displayed, the normal vector is pointing toward 6P!M+PO
you. (Y!@,rKd
Up Vector Ut8yA"Y~
The Up Vector is a vector in 3D space that is used to orient the projection plane t*^Q`V wQ
for the irradiance map. The plane is defined so that the Up Vector is parallel to the Ohnd:8E
vertical side of the plane. The irradiance incident on the selected surface is 5"6Y=AuQ6
projected onto this plane. When the map is displayed, the up vector will point ;
eq^m,oz
toward the top of the screen.