站长说的很对,补充一下: ),)]gw71QW
Normal Vector 5<ycF_
The Normal Vector is a vector in 3D space that is used to orient the projection Sf\mg4,
plane for the irradiance map. The plane is defined to be perpendicular to the I(Yyg,1Z
Normal Vector, and the irradiance incident on the selected surface is projected [nlW}1)46
onto this plane. When the map is displayed, the normal vector is pointing toward |ldRs'c{
you. K(HP PM\
Up Vector U{o0Posg
The Up Vector is a vector in 3D space that is used to orient the projection plane r#pC0Yj!3
for the irradiance map. The plane is defined so that the Up Vector is parallel to the 5A6d]
vertical side of the plane. The irradiance incident on the selected surface is MLcc
projected onto this plane. When the map is displayed, the up vector will point Ui7S8c#tH
toward the top of the screen.