站长说的很对,补充一下: QdTe!f|
Normal Vector Z C93C7lJ
The Normal Vector is a vector in 3D space that is used to orient the projection .#@D n(
plane for the irradiance map. The plane is defined to be perpendicular to the d0B+syl&4l
Normal Vector, and the irradiance incident on the selected surface is projected W~tOH=9>
onto this plane. When the map is displayed, the normal vector is pointing toward !7oy%{L
you. vo$66A
Up Vector <C77_t
The Up Vector is a vector in 3D space that is used to orient the projection plane V.#8-?z
for the irradiance map. The plane is defined so that the Up Vector is parallel to the s2v*
vertical side of the plane. The irradiance incident on the selected surface is `/zt&=`VB
projected onto this plane. When the map is displayed, the up vector will point !_) ^bRd
toward the top of the screen.