站长说的很对,补充一下: \0mb
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Normal Vector )$`wIp
The Normal Vector is a vector in 3D space that is used to orient the projection (tCUlX2
plane for the irradiance map. The plane is defined to be perpendicular to the p=C%Hmd5E
Normal Vector, and the irradiance incident on the selected surface is projected H"C[&r
onto this plane. When the map is displayed, the normal vector is pointing toward srYJp^sC
you. d3W0-INL
Up Vector j'aHF#_
The Up Vector is a vector in 3D space that is used to orient the projection plane LwhyE:1
for the irradiance map. The plane is defined so that the Up Vector is parallel to the oyNSh8c7c
vertical side of the plane. The irradiance incident on the selected surface is ] )F7)
projected onto this plane. When the map is displayed, the up vector will point y_HN6
toward the top of the screen.