站长说的很对,补充一下: 1aQm r=,
Normal Vector G<M0KU(
The Normal Vector is a vector in 3D space that is used to orient the projection m^!:n$
plane for the irradiance map. The plane is defined to be perpendicular to the gUNhN1=
Normal Vector, and the irradiance incident on the selected surface is projected :h5G|^
onto this plane. When the map is displayed, the normal vector is pointing toward N"}>);r
you. "]#Ij6ml
Up Vector ?HJh;96B
The Up Vector is a vector in 3D space that is used to orient the projection plane S=ZZ[E_~S
for the irradiance map. The plane is defined so that the Up Vector is parallel to the s]%Cz \
vertical side of the plane. The irradiance incident on the selected surface is ~v%6*9
projected onto this plane. When the map is displayed, the up vector will point 4^uSW&`;/
toward the top of the screen.