站长说的很对,补充一下: @,63%
Normal Vector #Pz},!7
The Normal Vector is a vector in 3D space that is used to orient the projection ;@@1$mzK
plane for the irradiance map. The plane is defined to be perpendicular to the OwwlQp ~!J
Normal Vector, and the irradiance incident on the selected surface is projected y+XB
onto this plane. When the map is displayed, the normal vector is pointing toward $#dPM*E
you. O0{M3-
Up Vector |"Js iT
The Up Vector is a vector in 3D space that is used to orient the projection plane U'nz3
for the irradiance map. The plane is defined so that the Up Vector is parallel to the 9LkP*$2"M<
vertical side of the plane. The irradiance incident on the selected surface is zhDmZ
projected onto this plane. When the map is displayed, the up vector will point #qk A*WP
toward the top of the screen.